Added(A)/Deleted(D) following books

 A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_1.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_10.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_11.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_13.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_2.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_3.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_4.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_5.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_6.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_7.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_9.ipynb
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main1.png
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main2.png
A  Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main3.png
A  sample_notebooks/AumkarRane/Chapter9.ipynb
A  sample_notebooks/DevikaRaj/Chapter6.ipynb

16 files changed, 3963 insertions, 0 deletions

diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_1.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_1.ipynb
new file mode 100644
index 00000000..962a1e31
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_1.ipynb
@@ -0,0 +1,62 @@
+{
+ "metadata": {
+  "name": "CHAPTER 1"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 1:Introduction To Microwaves"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1, Page no:6"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Given data\nR   = 1.2;      #ratio of free space wavelength of a microwave signal to its wavelength when prop. through a dielectric medium\n\n# Calculations\n# lamda = lamda0/sqrt(er);\n# er    = (lamda0/lamda)**2;\n#let lamda0/lamda  = R\n\ner  = (R)**2;        # Dielectric constant of medium\n\n#Output\nprint'The Dielectric constant of medium = %3.2f'%er;\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "The Dielectric constant of medium = 1.44\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2, Page no:8"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n#Given data\nRmax        = 112;      # Max permissable range in Kms\nH1          = 256;      # Ht of the antenna in m\n# Calculations\n#Rmax  = 4(math.sqrt(H1) + math.sqrt(H2));\n# H2    = ((Rmax/4)-math.sqrt(H1))**2;\nH2    = ((Rmax/float(4))-math.sqrt(H1))**2;      # Ht of other antenna\n# Output\nprint'Height of other antenna = %d m'%H2;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Height of other antenna = 144 m\n"
+      }
+     ],
+     "prompt_number": 1
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_10.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_10.ipynb
new file mode 100644
index 00000000..c30c38d5
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_10.ipynb
@@ -0,0 +1,314 @@
+{
+ "metadata": {
+  "name": "CHAPTER 10"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 10:Radar Systems Types And Applications"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:496"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nc       = 3*10**8;           # velocity of EM waves in m/s\nf       = 10*10**9;           # carrier freq in Hz\nfm      = 100;               # freq of modlating signal\ndphi    = 10;                # separation b/w tx FM signal and demod echo signal in degrees\n\n# Calculations\nTp      = dphi/float((360*fm));    # round trip propagation time\nR       = (c*Tp)/float(2);         # target range\n\n# Result\nprint'Target Range = %3.2f Km'%(R/float(1000));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Target Range = 41.67 Km\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:496"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 10*10**9;          # center freq. in Hz\nf_us    = 60*10**3;          # upsweep freq. in Hz\nf_ds    = 80*10**3;          # down sweep freq. in Hz\nfm      = 100;               # modulation freq. in Hz\nB       = 2*10**6;           # sweep bandwidth in Hz\nc       = 3*10**8;           # vel. of EM waves in m/s\nT       = 5*10**-3;\n\n# Calculations\nfd      = (f_ds - f_us)/float(2);      \ndf      = (f_ds + f_us)/float(2); \nR       = (c*T*df)/float((2*B));       # range in m\n# fd   = (2*Vr*f)/float(c);\nVr      = (c*fd)/float((2*f));         # target radial velocity\nVr_kmph = Vr*(18/float(5));            # target radial velocity in kmph\nVr_nmph = Vr_kmph/float(1.85);         # target radial velocity in Nautical miles per hour\n\n#Result\nprint'Target Range = %3.2f Km\\n'%(R/float(1000)),'Radial velocity = %3.1f Nmi/hr'%Vr_nmph;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Target Range = 26.25 Km\nRadial velocity = 291.9 Nmi/hr\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:497"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nVr = 150\nc  = 3*10**8;\ndf1= 10**6;\n# fd   = (2*Vr)/lamda  = (2*Vr*f)/c\n# for 'Vr' and 'c' as constant(for a given radial velocity,Vr is constant)\n# fd   = K.f where 'f' is the operating frequency and K = (2*Vr)/c\n# Therefore df = \u00b1 1 Mhz around the center frequency\nk = (2*Vr)/float(c);\ndf_d = df1*k\n\n#  Result\nprint'Doppler shift due to carrier frequency sweep = \u00b1%d Hz'%df_d;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Doppler shift due to carrier frequency sweep = \u00b11 Hz\n"
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:497"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 10*10**9;          # operating frequency in Hz\nf_us    = 100*10**3;         # upsweep freq\nf_ds    = 100*10**3;         # downsweep freq\nTus     = 5*10**-3;          # up-sweep period\nTds     = 5*10**-3;          # down-sweep period\nT       = 10*10**-3           \nB       = 10*10**6;          # sweep bandwidth\nc       = 3*10**8;           # vel of EM waves in m/s\nf_us_b  = 80*10**3;          # upsweep freq in fig b\nf_ds_b  = 50*10**3;          # downsweep freq in fig b\nf_us_c  = 50*10**3;          # upsweep freq in fig b\nf_ds_c  = 80*10**3;          # downsweep freq in fig b\n\n# Calculations\n# a\nfd      = (f_us - f_ds)/float(2);      # doppler shift\ndf      = (f_us + f_ds)/float(2);      # freq diff\nVr_a    = (c*fd)/float((2*f));         # radial velocity\nR       = (c*Tus*df)/float((2*B));     # Range\nif Vr_a == 0:\n    print'Case a:\\nRadial velocity = %d'%Vr_a ,'\\nRange = %3.3f Km\\n'%(R/1000);\n#b\nfd      = (f_us_b - f_ds_b)/2;      # doppler shift\ndf_b    = (f_us_b + f_ds_b)/2;      # freq difference due to range\nR_b     = (c*T*df_b)/(2*B);         # Range\nVr_b    = (c*fd)/(2*f);             # radial velocity\n\nprint'Case b:\\nRadial velocity = %3.2fm/s'%Vr_b,'\\n Range = %3.3f Km\\n' %(R_b/1000);\nprint 'As the up-sweep frequency difference is less than downspeed freq diff, this implies that doppler shift is\\ncontributing towards an increase in the echo signal freq. so, target is moving towards radar\\n'\n\n# c\nfd      = (f_us_c - f_ds_c)/2;      # doppler shift\ndf_c    = (f_us_c + f_ds_c)/2;      # freq difference due to range\nR_c     = (c*T*df_c)/(2*B);         # Range\nVr_c    = (c*fd)/(2*f);             # radial velocity\nprint'Case c:\\n Radial velocity = %3.2fm/s' %abs(Vr_c),'\\n Range = %3.3f Km\\n' %(R_c/1000)\nprint' As the up-sweep frequency difference is greater than downspeed freq diff, this implies that doppler shift is\\n contributing towards an decrease in the echo signal freq. so, target is moving away from radar';",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Case a:\nRadial velocity = 0 \nRange = 7.500 Km\n\nCase b:\nRadial velocity = 225.00m/s \n Range = 9.750 Km\n\nAs the up-sweep frequency difference is less than downspeed freq diff, this implies that doppler shift is\ncontributing towards an increase in the echo signal freq. so, target is moving towards radar\n\nCase c:\n Radial velocity = 225.00m/s \n Range = 9.750 Km\n\n As the up-sweep frequency difference is greater than downspeed freq diff, this implies that doppler shift is\n contributing towards an decrease in the echo signal freq. so, target is moving away from radar\n"
+      }
+     ],
+     "prompt_number": 28
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:504"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Variable Declaration\nf       = 10*10**9;          # operating freq in Hz\nPRF     = 1000;              # pulse rep. rate\nVr      = 1000;              # radial velocity\nc       = 3*10**8;            # vel. of EM waves in m/s\n\n# Calculations\nfd      = (2*Vr*f)/c        # true doppler shift\nfA1     = abs(((fd%PRF) - PRF))%PRF\nfA2     = abs(((fd%PRF) + PRF))%PRF\n\n\nif fA1 < fA2:\n    fd  = fA1;         # apparent doppler shift\nelse:\n    fd  = fA2;         # apparent doppler shift\nVr      = (c*fd)/(2*f);     # radial velocity in m/s\n\n# output\nprint'Radial velocity = %3.2f m/s' %Vr, '\\n The radar measures the target to be moving away from the radial velocity at %3.2f m/s though in reality\\n it is moving towards the radar with a velocity of 1000 m/s'%abs(Vr);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Radial velocity = 5.00 m/s \n The radar measures the target to be moving away from the radial velocity at 5.00 m/s though in reality\n it is moving towards the radar with a velocity of 1000 m/s\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:507"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nlamda   = 3*10**-2;      # Operating Wavelength in m\nPRF     = 2000;          # pulse rep. freq in Hz\nn       = 1;             # for lowest blind speed\n\n# Calculations\nLBS     = ((n*lamda)/2)*PRF; # lowest blind speed\nVb_kmph = LBS*(18/float(5))       # lowest blind speed in kmph\n\n# Result\nprint'Lowest Blind speed = %d Kmph' %Vb_kmph;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Lowest Blind speed = 108 Kmph\n"
+      }
+     ],
+     "prompt_number": 21
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:510"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Given data\nR       = 100;          # Range in kms\nPRR     = 10*10**3;     # pulse rep. rate in Hz\nc       = 3*10**5;      # vel. in km/s\n\n# Calculations\nPRI     = 1/float(PRR);        # pulse rep. interval\nRa      = (R%(c*PRI/float(2)));      # apparent range in km\n\n# Output\nprint'Apparent Range = %d Km\\n'%Ra;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Apparent Range = 10 Km\n\n"
+      }
+     ],
+     "prompt_number": 22
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 12,Page No:511"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nRa      = 25;       # Apparent Range in km\nPRF     = 2000;     # Pulse rep. freq.\nc       = 3*10**5;   # vel. of EM waves in km/s\nNr      = 3;        # Range zone\n\n# Calculations\nR       = Ra + ((c/float(2))*((Nr - 1)/float(PRF)));    # true range in km\n\n# Result\nprint'True Range of the target = %d Km'%R;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "True Range of the target = 175 Km\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 13,Page No:511"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPRF_1   = 750;      # pulse rep. freq in Hz\nPRF_2   = 1000;     # pulse rep. freq in Hz\nPRF_3   = 1250;     # pulse rep. freq in Hz\nRa_1    = 100;      # Apparent range for PRF_1\nRa_2    = 50;       # Apparent range for PRF_2\nRa_3    = 20;       # Apparent range for PRF_3\nc       = 3*10**5;  # Vel of EM waves in Km/s\n\n# Calculations\nR12 = \nfor Nr in range(1,6):\n    R12       = Ra_1 + ((c/2)*((Nr - 1)/PRF_1))    # true range in km\n    R23       = Ra_2 + ((c/2)*((Nr - 1)/PRF_2))   # true range in km\n    R33      = Ra_3 + ((c/2)*((Nr - 1)/PRF_3))  # true range in km\n\n# Output\nprint R12;\nprint'Possible True Range measurements for 750 PPS\\n';\n#print' = %dkm \\n',R1;\nprint'Possible True Range measurements for 1000 PPS\\n'\n#print' = %dkm \\n',R2;\nprint'Possible True Range measurements for 1250 PPS\\n'\n#print' = %dkm \\n',R3;\n#print'The shortest possible range that has been measured at all PRFs is %d Km True Range = %d km',R1(3),R1(3);\n   \n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "100\nPossible True Range measurements for 750 PPS\n\nPossible True Range measurements for 1000 PPS\n\nPossible True Range measurements for 1250 PPS\n\n"
+      }
+     ],
+     "prompt_number": 30
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 14,Page No:528"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nTe      = 4      # Expanded pulse width in usec\nf1      = 50     # RF freq in Mhz\nf2      = 70     # RF freq in Mhz\n\n# Calculations\nB       = f2 - f1;      # Signal bandwidth\nTc      = 1/float(B);          # Compressed pulse width in us\nCR      = Te/float(Tc);         # compression ratio\n\n# Result\nprint'Compression Ratio = %d\\n'%CR,'Width of compressed pulse = %3.2f us'%Tc;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Compression Ratio = 80\nWidth of compressed pulse = 0.05 us\n"
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 15,Page No:528"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 10*10**9;      # operating freq in Hz\nc       = 3*10**8;        # vel. of EM waves in m/s\nAe      = 2;             # Antenna aperture in m\nR       = 10*10**3;       # Target Range in m\n\n# Calculations\nlamda   = c/float(f);          # Wavelength in m\nbw3db   = lamda/float(2);      # 3dB beamwidth in radian\nLeff    = bw3db * R;    # effective length\nXs      = (R*lamda)/float((2*Leff));   # Cross range resolution\n\n# Result\nprint'Effective Length = %d m'%Leff;\nprint'Cross range resolution = %d m'%Xs;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Effective Length = 150 m\nCross range resolution = 1 m\n"
+      }
+     ],
+     "prompt_number": 32
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 16,Page No:541"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nR       = 6000;     # Target Range\nc       = 3*10**8;   # speed of light in m/s\n\n# Calculations\nt       = (2*R)/float(c);  # round trip time\n\n# Result\nprint'Round Trip time = %d us'%(t/float(10**-6));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Round Trip time = 40 us\n"
+      }
+     ],
+     "prompt_number": 33
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 17,Page No:542"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable declaration\nv       = 250;            # velocity in m/s\nlamda   = 10.6*10**-6     # operating wavelength\ntheta   = 60;             # angle of depression\n\n# Calculations\nVr      = v*math.cos(theta*math.pi/float(180));     # radial velocity\nfd      = (2*Vr)/float(lamda);                 # doppler shift\n\n# Result\nprint'Doppler Shift = %3.2f Mhz'%(fd*10**-6);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Doppler Shift = 23.58 Mhz\n"
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 18,Page No:542"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nB       = 10**6;     # Bandwidth in Mhz\nc       = 3*10**8;    # speed of light in m/s\n\n# Calculations\nRR      = c/float((2*B));  # Range Resolution in m\n\n# Result\nprint'Range Resolution = %d m\\n'%RR;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Range Resolution = 150 m\n\n"
+      }
+     ],
+     "prompt_number": 34
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_11.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_11.ipynb
new file mode 100644
index 00000000..bb3c4fa2
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_11.ipynb
@@ -0,0 +1,398 @@
+{
+ "metadata": {
+  "name": "CHAPTER 11"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 11:Satellites And Satellite Communication "
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:567"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nh       = 150;              # height of satellite from earth in km\nG       = 6.67*10**-11;      # Gravitational constant\nM       = 5.98*10**24;       # mass of the earth in kg\nRe      = 6370;             # radius of earth in km\n\n# Calculations\nu       = G*M\nV       = math.sqrt(u/float(((Re + h)*10**3))) # orbital velocity\nV1      = V/float(1000);                       # orbital velocity in km/s\n\n# Result\nprint'Orbital velocity = %3.3f km/s'%V1;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Orbital velocity = 7.821 km/s\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:568"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nAp_Pe_diff  = 30000;        # difference between apogee and perigee in Km\na           = 16000;        # semi major axis of orbit\n\n# Calculations\ne           =  Ap_Pe_diff/float((2*a));    # Eccentricity\n\n# Result\nprint'Eccentricity = %3.2f'%e;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Eccentricity = 0.94\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:568"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na1      = 18000;            # semi major axis of the elliptical orbits of satellite 1\na2      = 24000;            # semi major axis of the elliptical orbits of satellite 2\n\n# Calculations\n# T    = 2*math.pi*math.sqrt(a**3/float(u));\n#let K = T2/float(T1);\nK       = (a2/float(a1))**(3/float(2));    # Ratio of orbital periods\n\n# Result\nprint'The orbital period of satellite-2 is %3.2f times the orbital period of satellite-1'%K;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "The orbital period of satellite-2 is 1.54 times the orbital period of satellite-1\n"
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:569"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nh       = 35800;            # height of satellite orbit from earth in km\nG       = 6.67*10**-11;      # Gravitational constant\nM       = 5.98*10**24;       # mass of the earth in kg\nRe      = 6364;             # radius of earth in km\ni       = 2;                # inclination angle\n\n# Calculations\nu       = G*M\nr       = Re+h;\nVi      = (math.sqrt(u/float(r*10**3)))*math.tan((i*math.pi)/float(180));     # magnitude of velocity impulse\nV       = Vi                                # magnitude of velocity impulse in m/s\n\n# Result\nprint'Magnitude of velocity impulse = %d m/s'%V;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Magnitude of velocity impulse = 107 m/s\n"
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:571"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nh       = 13622;        # ht of circular orbit from earth's surface\nRe      = 6378;         # Radius of earth in km\n\n# Calculations\nR       = Re+h;         # Radius of circular orbit\npimax   = 180 - (2*math.acos(Re/float(R)))*(180/float(math.pi));   # Maximum shadow angle\neclipmax_time = (pimax/float(360))*24;             # maximum daily eclipse duration\n\n# Result\nprint'maximum shadow angle = %3.1f\u00b0\\n'%pimax,'Maximum daily eclipse duration = %3.2fhours'%eclipmax_time;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "maximum shadow angle = 37.2\u00b0\nMaximum daily eclipse duration = 2.48hours\n"
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:572"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\nh       = 35786;        # ht of geo.stationary orbit above earth surface\nT       = 365;          # time in days\nr       = 6378          # radius of earth in km\n\n# ie(t) = 23.4*sin(2*%pi*t/T)\n# for a circular orbit of 20000 km radius ,phi = 37.4\u00b0 ,Therefore, the time from first day of eclipse to equinox is given by substituting ie(t) = 37.4/2 = 18.7\u00b0\nphi     = 37.4\nie      = (phi/2)*(math.pi/180)\nk       = 23.4*(math.pi/180)\nt       = (365/(2*math.pi))*math.asin((ie/k)) \n# for geostationary orbit\nphimax  = 180 - 2*(math.acos(r/(r+h)))*(180/math.pi)\nt_geo   = (365/(2*math.pi))*math.asin((8.7*math.pi/180)/k)\n\n# Output\nprint'Total time from first day of eclipse to last day of eclipse = %3.1f days'%t\nprint '\\nTotal time from first day of eclipse to last day of eclipse for geostationary orbit = %3.2f days'%t_geo\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Total time from first day of eclipse to last day of eclipse = 53.8 days\n\nTotal time from first day of eclipse to last day of eclipse for geostationary orbit = 22.13 days\n"
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:600"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\nm       = 100;      # mass of satellite\nV       = 8000;     # orbital velocity in m/s\nRe      = 6370;     # radius of earth in Km\nH       = 200;      # satellite height above earth surface\n\n# Calculations\nCF      = (m*V**2)/float(((Re+H)*10**3));       # centrifugal force\n\n# output\nprint'Centrifugal Force = %d Newtons'%CF;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Centrifugal Force = 974 Newtons\n"
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:601"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nApogee  = 30000;        # Apogee pt of satellite elliptical orbit\nPerige  = 1000;         # perigee pt of satellite elliptical orbit\n\n# Calculations\na       = (Apogee + Perige)/float(2);  # semi major axis\n\n# Result\nprint'Semi-major axis = %d Km'%a;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Semi-major axis = 15500 Km\n"
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:601"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# variable Declaration\nfarth   = 30000;        # farthest point in satellite elliptic eccentric orbit\nclosest = 200;          # closest point in satellite elliptic eccentric orbit\nRe      = 6370;         # Radius of earth in km\n\n# Calculations\nApogee  = farth + Re;   # Apogee in km\nPerigee = closest + Re; # perigee in km\na       = (Apogee + Perigee)/float((2));       # semi-major axis\ne       = (Apogee - Perigee)/float((2*a));     # orbit eccentricity\n\n# Result\nprint'Apogee = %d km\\n'%Apogee;\nprint'Perigee = %d km\\n'%Perigee;\nprint'orbit eccentricity = %3.3f'%e;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Apogee = 36370 km\n\nPerigee = 6570 km\n\norbit eccentricity = 0.694\n"
+      }
+     ],
+     "prompt_number": 14
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 10,Page No:604"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\ne       = 0.5;      # orbit eccentricity\nae      = 14000;    # from fig. the distance from center of ellipse to the centre of earth\n\n# Calculations\na       = ae/float(e);         # semi major axis\napogee  = a*(1 + e);    # Apogee in km\nperige  = a*(1 - e);    # perigee in km\n\n# output\nprint'Apogee = %d km\\n'%apogee,'Perigee = %d km'%perige;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Apogee = 42000 km\nPerigee = 14000 km\n"
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:605"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# variable Declaration\nG       = 6.67*10**-11;      # Gravitational constant\nM       = 5.98*10**24;       # mass of the earth in kg\nRe      = 6370*10**3;        # radius of earth in m\n\n# Calculations\nu       = G*M\nVesc    = math.sqrt(2*u/float(Re));\nVes     = Vesc/float(1000);    # escape velocity in km/s\n\n# Result\nprint'Escape velocity = %3.1f km/s'%Ves;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Escape velocity = 11.2 km/s\n"
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 12,Page No:605"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na       = 25000*10**3;      # semimajor axis in m from fig\nG       = 6.67*10**-11;     # Gravitational constant\nM       = 5.98*10**24;      # mass of the earth in kg\nh = 0\n\n# Calculations\nu       = G*M;\nT       = 2*math.pi*math.sqrt((a**3)/float(u));\nhr          = T/float(3600);                        # conv. from sec to hrs and min\nt           = (T%3600);               # conv. from sec to hrs and min\nmi          = t/float(60);                          # conv. from sec to hrs and min\n\n# Result\nprint'Orbital time period = %d'%hr,'Hours %d minutes'%mi;\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Orbital time period = 10 Hours 55 minutes\n"
+      }
+     ],
+     "prompt_number": 16
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 13,Page No:605"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# variable Declaration\napogee  = 35000;        # farthest point in kms\nperigee = 500;          # closest point in kms\nr       = float(6360);         # radius of earth in kms\nG       = 6.67*10**-11   # gravitational constant\nM       = 5.98*10**24;   # mass of earth in kgs\n# calculations\n#funcprot(0)\napogee_dist = apogee + r       # apogee distance in kms\nperigee_dist= perigee+r ;      # perigee distance in kms\na           = (apogee_dist + perigee_dist)/2;   # semi-major axis of elliptical orbit\nT           = (2*math.pi)*math.sqrt((a*10**3)**3/(G*M));          # orbital time period\nhr          = T/float(3600)                        # conv. from sec to hrs and min\nt           = T%3600               # conv. from sec to hrs and min\nmi          = t/60                          # conv. from sec to hrs and min\nu           = G*M\nVapogee     = math.sqrt(u*((2/(apogee_dist*10**3)) - (1/(a*10**3))));      # velocity at apogee point\nVperigee    = math.sqrt((G*M)*((2/(perigee_dist*10**3)-(1/(a*10**3)))))    # velocity at perigee point\n\n# Result\nprint'Orbital Time Period = %d Hrs'%hr,'%d min' %mi \nprint'Velocity at apogee = %3.3f Km/s' %(Vapogee/1000)\nprint 'Velocity at perigee = %3.3f Km/s'%(Vperigee/1000)\nprint'Note: Calculation mistake in textbook in finding velocity at apogee point'\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Orbital Time Period = 10 Hrs 20 min\nVelocity at apogee = 1.656 Km/s\nVelocity at perigee = 9.987 Km/s\nNote: Calculation mistake in textbook in finding velocity at apogee point\n"
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 14,Page No:606"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nra_S_rp     = 50000;        # sum of apogee and perigee distance\nra_D_rp     = 30000;        # difference of apogee and perigee distances\n\n# Calculations\ne           = ra_D_rp/float(ra_S_rp);  # eccentricity\n\n# Result\nprint'Target eccentricity = %3.1f'%e;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Target eccentricity = 0.6\n"
+      }
+     ],
+     "prompt_number": 17
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 15,Page No:607"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Given data\na       = 20000;            # semi major axis of elliptical sate. orbit in kms\nb       = 16000;            # semi minor axis of elliptical sate. orbit in kms\n\n# calculations\n# a = (ra + rp)/2\n# b = math.sqrt(ra*rp)\n# let k = (ra + rp)\n# let l = ra*rp\nk       = 2*a;              # ra+ rp ----------------1\nl       = b**2;              # ra*rp -----------------2\n# ra**2 -40000ra + 256000000\n\n\n\nAp = (k - (math.sqrt(k**2-4*1*l)))/(2*1)\nPe = (k + (math.sqrt(k**2-4*1*l)))/(2*1)\n\n\n\n\n\nprint'Apogee distance = %d km\\n'%Ap,'Perigee distance = %d km' %Pe;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Apogee distance = 8000 km\nPerigee distance = 32000 km\n"
+      }
+     ],
+     "prompt_number": 26
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 16,Page No:607"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable delaration\nH       = 35800;        # height of orbit in kms\nre      = 6364;         # radius of earth in kms\ni       = 2;            # angle of inclination in degrees\n\n# Calculations\nr       = H+re;         # radius of orbit in kms\nlamdamax = i;           # max latitude deviation\nlong_dev = (i**2)/float(228);   # max. longitude deviation\ndisp_lamda = (r*i*math.pi/180) # max disp in km due to lamdamax\nmax_disp1  = disp_lamda*(long_dev/lamdamax) # max disp.due to max.longitude deviation\n\n# Result\nprint'Maximum deviation in latitude = %d\u00b0'%lamdamax\nprint'Maximum deviation in longitude = %3.4f\u00b0'%long_dev\nprint'Maximum displacements due to latitude displacement = %d Km'%disp_lamda\nprint'Maximum displacements due to longitude displacement = %3.1f Km\\n'%max_disp1 ;\n    \n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Maximum deviation in latitude = 2\u00b0\nMaximum deviation in longitude = 0.0175\u00b0\nMaximum displacements due to latitude displacement = 1471 Km\nMaximum displacements due to longitude displacement = 12.9 Km\n\n"
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 17,Page No:608"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nr       = 42164;        # orbital radius in kms\nDlamda_max = 500;       # max displacement due to latitude deviation\n\n# Calculations\ni   = Dlamda_max/float(r);     # angle of inclination in radians\ni_deg = i*180/math.pi;      # rad to deg conv\n\n# Result\nprint'Angle of inclination = %3.2f\u00b0'%i_deg;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Angle of inclination = 0.68\u00b0\n"
+      }
+     ],
+     "prompt_number": 17
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 18,Page No:609"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nH   = 35786;        # ht of orbit from earth surface\nRe  = float(6378)          # radius of earth in kms\n\n# Calculations\n# For theoretical max coverage angle,elevation angle E = 0 \nE = 0\n# max coverage angle = 2amax\n# 2amax = 2asin(Re/(Re+H)cosE)\namax = 2*math.asin((Re/(Re+H))*math.cos(E))\namax_deg = amax*180/math.pi     # rad to deg conversion\nD   = math.sqrt( Re**2 + (Re+H)**2 - 2*Re*(Re + H)*math.asin(E + math.asin((Re/(Re+H))*math.cos(E)))) # Max slant range\n\n# Result\nprint'Maximum Coverage angle = %3.1f\u00b0'%amax_deg\nprint'Maximum slant Range = %d Km'%D;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Maximum Coverage angle = 17.4\u00b0\nMaximum slant Range = 41671 Km\n"
+      }
+     ],
+     "prompt_number": 22
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_13.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_13.ipynb
new file mode 100644
index 00000000..d51a7517
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_13.ipynb
@@ -0,0 +1,293 @@
+{
+ "metadata": {
+  "name": "CHAPTER 13"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 13:Microwave Communication Link Basic Design Considerations "
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:670"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 6;            # microwave terrestrial comm link oper. freq in Ghz\nD       = 50;           # single hop path length in miles\n# mid way of path length\nD1      = 25;\nD2      = 25;\nN       = 3;            # N value for third fresnal zone\n\n# calculations\nF1      = 72.2*((D1*D2)/float((D*f)))**0.5;     # first fresnel zone\nF3      = F1*math.sqrt(N);                    # Third fresnal zone\n\n# Result\nprint'First Fresnel zone distance = %3.1f feet\\n'%F1,'Third Fresnel zone distance = %3.1f feet\\n'%F3;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "First Fresnel zone distance = 104.2 feet\nThird Fresnel zone distance = 180.5 feet\n\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:670"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 4.5;          # microwave terrestrial comm link oper. freq in Ghz\nD       = 40;           # single hop path length in miles\nhant    = 200;          # antenna ht. above surface of earth\n# from fig\nD1      = 5;\nD2      = 35;\nK       = 1;            # for normal case\n\n# calculations\nF1      = 72.2*((D1*D2)/float((D*f)))**0.5;     # first fresnel zone\n# computing curvature 'h' of earth at a distance of 10 miles from Transmitter if given by (D1*D2)/(1.5*K)\nh       = (D1*D2)/float((1.5*K));             # curvature of earth in feet\nPLabove = hant - h;                    # path line is PLabove feet above surface of earth\nhmaxtol = PLabove - F1;                # max tolerable height in feet\n\n# Result\nprint'Maximum tolerable height of obstacle above surface of earth = %3.2f feet'%hmaxtol;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Maximum tolerable height of obstacle above surface of earth = 12.14 feet\n"
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:671"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 4.5;          # microwave terrestrial comm link oper. freq in Ghz\nD       = 40;           # single hop path length in miles\nhant    = 200;          # antenna ht. above surface of earth\n# from fig\nD1      = 5;\nD2      = 35;\nK       = 2/float(3);            # K-factor\n\n# calculations\nF1      = 72.2*((D1*D2)/float((D*f)))**0.5;     # first fresnel zone\n# computing curvature 'h' of earth at a distance of 10 miles from Transmitter if given by (D1*D2)/(1.5*K)\nh       = (D1*D2)/float((1.5*K));             # curvature of earth in feet\nPLabove = hant - h;                    # path line is PLabove feet above surface of earth\nif PLabove < F1:\n    print'Available clearance above the surface of earth = %d feet'%PLabove,'\\nRequired first fresnal zone clearance = %3.1f feet'%F1,'So it would be obstructed';\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Available clearance above the surface of earth = 25 feet \nRequired first fresnal zone clearance = 71.2 feet So it would be obstructed\n"
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:671"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nUF      = 2*10**-4;      # unavailability factor\n\n# Calculations\noutrage_t = UF*8760;    # outrage time in hours per year\n\n# Result\nprint'Outrage time = %3.3f hours per year'%outrage_t;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Outrage time = 1.752 hours per year\n"
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:671"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# variable Declaration\nPL      = 50;       # path length in miles from fig\nFM      = 40;       # fade margin in dB\nP_fm_ex = 7*10**-5;  # prob. of fade margin getting exceeding\nP_fm_ex_50db    = 6*10**-6;  # prob. of fade margin getting exceeding for fade margin 50dB\np_fig_30m_40db  = 2*10**-5;  # prob fig for patl length of 30miles and fade margin 40dB \n\n# Calculations\nimpr_prob_a = P_fm_ex/float(P_fm_ex_50db);    # improvement in prob. of fade margin for a\nimpr_prob_b = P_fm_ex/float(p_fig_30m_40db);   # improvement in prob. of fade margin for b\n\n# Result\nprint'(a):\\n Improvement in probability of fade margin = %3.1f\\n'%impr_prob_a,'(b):\\n Improvement in probability of fade margin = %3.1f\\n'%impr_prob_b;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "(a):\n Improvement in probability of fade margin = 11.7\n(b):\n Improvement in probability of fade margin = 3.5\n\n"
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:672"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\nUF_sh   = 0.01;     # unavail. factor for single hop\nIF_SD   = 100;      # improvement factor due to space diversity\n\n# Calculations\nUF_4hl  = 4* UF_sh/float(100);     # unavail. factor for 4 hop link and conv from %\nUF      = UF_sh/float((100*IF_SD)); # unavail. factor for single hop link if it employs space diversity\n\n# Output\nprint'unavail. factor for 4 hop link = %3.4f\\n'%UF_4hl,'unavail. factor for single hop link if it employs space diversity = %3.0e'%UF;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "unavail. factor for 4 hop link = 0.0004\nunavail. factor for single hop link if it employs space diversity = 1e-06\n"
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:672"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 3.5;              # operating freq. of microwave link in Ghz\nD       = 30;               # single hop path length in miles\na       = 1;                # roughness\nb       = 0.5;              # humid climate\nF       = 40;               # fade margin in dB\n\n# Calculations\nU       = a*b*2.5*10**-6 *f*D**3 *10**(-F/10);  # unavailability factor \nU1      = U*525600;                             # unavailabilty factor in minutes per year\nU4      = U1*4;      # unavailabilty factor for 4-hop link\n\n# Result\nprint'Outage Time = %3.1f minutes per year'%U4;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Outage Time = 24.8 minutes per year\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:673"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\n# D2 = 2*D1            # path length is doubled\n# F2 = F1+10;          # fade margin is increased by 10dB\n# f2 = 1.25f1          # frequency operation increased by 25 %\n\n#(U1/U2)  = (f1* D1**3 * 10**(-F1/10))/ (f1* D1**3 * 10**(-F1/10))\n# sub above values\n#(U1/U2)  = (f1* D1**3 * 10**(-F1/10)) / (1.25*f1*8*D1**3*10**(-F1/10)*10**-1) = 1\nprint'Unavailability Factor remains unaltered';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Unavailability Factor remains unaltered\n"
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:673"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\nprint'The improvement factor is proportional to square of antenna spacing.Therefore,it will increase by a factor of 4\\nConsequently,the unavailability factor and hence the outrage time will also reduce by a factor of 4';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "The improvement factor is proportional to square of antenna spacing.Therefore,it will increase by a factor of 4\nConsequently,the unavailability factor and hence the outrage time will also reduce by a factor of 4\n"
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 10,Page No:677"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\nDFM     = 40;       # dispersive fade margin\nFFM     = 30;       # flat fade margin\n\n# Calculations\nCFM     = -10*math.log10(10**(-FFM/float(10)) + 10**(-DFM/float(10)));\n\n# Output\nprint'Composite Fade Margin = %3.2f dB\\n'%CFM;\nprint'minus sign is wrongly printed in Textbook';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Composite Fade Margin = 29.59 dB\n\nminus sign is wrongly printed in Textbook\n"
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:677"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nDFM1    = 50;       # dispersive fade margin\nFFM     = 30;       # flat fade margin\nDFM2    = 40;       # dispersive fade margin\n\n# Calculations\nCFM1    = -10*math.log10(10**(-FFM/float(10)) + 10**(-DFM1/float(10)));\nCFM2    = -10*math.log10(10**(-FFM/float(10)) + 10**(-DFM2/float(10)));\nd_CFM   = CFM1 -CFM2;\n\n# Result\nprint'CFM increases by %3.2f dB for a 10 dB increase in DFM which is very Marginal'%d_CFM;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "CFM increases by 0.37 dB for a 10 dB increase in DFM which is very Marginal\n"
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 12,Page No:677"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 23;               # operating freq. of microwave link in Ghz\nD       = 10;               # single hop path length in miles\na       = 1;                # topographic factor\nb       = 0.5;              # climatic factor\nDFM     = 40;               # dispersive fade margin\nFFM     = 30;               # flat fade margin\n\n# Calculations\nCFM     = -10*math.log10(10**(-FFM/float(10)) + 10**(-DFM/float(10)));  # composite fade margin\nU       = a*b*2.5*10**-6 *f*D**3 *10**(-CFM/float(10));     # unavailability factor \nU1      = U*525600;                               # outrage time in min per year\n\n# Result\nprint'Outrage time = %3.2f minutes per year'%U1;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Outrage time = 16.62 minutes per year\n"
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 13,Page No:682"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nMTBF2    = 20000;       # microwave Tx output MTBF figure  \nMTBF3    = 60000;       # power amplifier portion of MTBF\n\n# Calculations\nMTBF1    = (MTBF2*MTBF3)/float((MTBF3-MTBF2)); \nimpr     = MTBF1-MTBF2      # improvement in MTBF if power amplifier not used\n\n# Result\nprint'Improvement in MTBF of transmitter if power amplifier is not used = %d hours'%impr;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Improvement in MTBF of transmitter if power amplifier is not used = 10000 hours\n"
+      }
+     ],
+     "prompt_number": 13
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_2.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_2.ipynb
new file mode 100644
index 00000000..cfb7ca54
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_2.ipynb
@@ -0,0 +1,104 @@
+{
+ "metadata": {
+  "name": "CHAPTER 2"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "    Chapter 2: Maxwell's Equations"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:33"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\n# \u00b5r1 = 3;     # relative permeability of region 1\n# \u00b5r2 = 5;     # relative permeability of region 2\n#  H1 = (4ax + 3ay -6az)A/m;   Magnetic field intensity\n# Therefore B1 = \u00b5o\u00b5r1H1\n#              = \u00b5o(12ax + 9ay -18az)A/m\n# since normal component of (B) is continuous across the interface\n# Therefore, B2 = \u00b5o[12ax + 9(\u00b5r2/\u00b5r1)ay -18(\u00b5r2/\u00b5r1)az]\n#               = \u00b5o[12ax + 15ay - 30az]\n#            H2 = [12/5ax + 15/5ay - 30/5az]A/m\n#            H2 = (2.4ax + 3ay - 6az)\nH2      = math.sqrt((2.4**2) + (3**2) + (6**2));\n\n# output\nprint'Magnetic field intensity in region- 2 = %3.3f A/m'%H2;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Magnetic field intensity in region- 2 = 7.125 A/m\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "    Example 10, Page No:40"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\n# D  = 3*10**-7 sin(6*10**7 - 0.35x)az\ner = 100;       # relative permitivity\n\n# Calculations\n# \u2202D/\u2202t =  3*10**-7 * 6*10**7* cos(6*10**7 - 0.35x)az\nA =  3*10**-7 * 6*10**7\n\n#output\nprint'Amplitude of displacement current density = %d A/m**2'%A;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Amplitude of displacement current density = 18 A/m**2\n"
+      }
+     ],
+     "prompt_number": 17
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "    Example 13,Page No:42"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math;\n\n# Variable Declaration\n\n#E = 20\u03c0 e**j(wt - \u03b2z)ax\n#H = Hm e**j(wt + \u03b2z)ay\nlamda = 1.8;         # wavelength in m\nc     = 3*10**8;     # vel. in m/s\ner    = 49;          # relative permitivity\nur    = 1;           # relative permeability\nEm    = 20*math.pi      # from the given expression\n\n# Calculations\nv     = c/float(math.sqrt(er));    # velocity of propagation of wave in medium with er rel.permitivity\nw     = (2*math.pi*v)/float(lamda);\n# let k = E/H\nk = (120*math.pi)*math.sqrt(ur/float(er));\nHm = Em/float(k);\n# sign of Hm can be determined by evaluating the maxwells eqn\n# V*E = \u2202B/\u2202x \n# V*E = -j20\u03c0 e**j(wt - \u03b2z)ay              ---------------- 1\n# -\u2202B/\u2202x = -juow Hm e**j(wt + \u03b2z)ay        ---------------- 2\n# comparing 1 and 2 singn of Hm must be positive\n\n# Output\nprint'w = %3.1e rad/s\\n'%w;\nprint'Hm = %3.2f A/m'%Hm;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "w = 1.5e+08 rad/s\n\nHm = 1.17 A/m\n"
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 14,Page No:42"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\nf       = 1000;     # frequency in Hz\nsigma   = 5*10**7;   # conductivity in mho/m\ner      = 1;        # relative permitivity \neo      = 8.85*10**-12;  # permitivity\n#J     = 10**8sin(wt-444z)ax A/float(m**2)\n\n# Calculations\nw       = 2*math.pi*f\n# J  = \u03c3E\n# E  = 10^8sin(wt-444z)ax/sigma\n# E  = 0.2sin(6280t-444z)ax\n# D  = eoerE\n# D  = 8.85*10**-12*0.2sin(6280t-444z)ax\n# \u2202D/\u2202t = 1.77*1088-12*6280cos(6280t - 444z)ax\nA     =  1.77*10**-12*6280\n#output\nprint'Amplitude of displacement current density = %3.2e A/m^2'%A;\nprint'\\nNote: calculation mistake in textbook';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Amplitude of displacement current density = 1.11e-08 A/m^2\n\nNote: calculation mistake in textbook\n"
+      }
+     ],
+     "prompt_number": 8
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_3.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_3.ipynb
new file mode 100644
index 00000000..033f972e
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_3.ipynb
@@ -0,0 +1,440 @@
+{
+ "metadata": {
+  "name": "CHAPTER 3"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 3:Transmission Media,Transmission Lines and Waveguides"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:65"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nLr      = 18;       # return loss in db\n\n# Calculations\n# Lr   = 20*math.log(1/float(p));      \np       = 1/10**(Lr/float(20));     # reflection co-efficient\nswr     = (1 + p)/(1 - p);      # standing wave ratio\n\n# Result\nprint'Reflection co-efficient is %3.3f\\n'%p,'SWR = %3.2f'%(swr);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Reflection co-efficient is 0.126\nSWR = 1.29\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:66"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPW  = 30*10**-6;     # pulse width in sec\nips = 20*10**-6;     # inter pulse separation\nv   = 3*10**8;       # propagation speed in m/s\n\n# Calculations\nT   = PW+ips+PW+ips+PW      # time duration of the pulse train for having 3 pulses on the line at a time\nl   = v*T;                  # minimum length of cable required\n\n# Result\nprint'Minimum length of cable required = %d km' %(l/float(1000));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Minimum length of cable required = 39 km\n"
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:66"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nRmsVmax    = 100;      # max value of RMS vtg\nRmsVmin    = 25;       # min value of RMS vtg\nZl         = 300;      # load impedance in ohm\n\n# Calculations\nVSWR       = RmsVmax/float(RmsVmin);   \n# wkt VSWR  = Zl/float(Zo); assuming Zl > Zo\nZo         = Zl/float(VSWR);   # charecteristic impedance in ohm\np          = (Zl - Zo)/float((Zl + Zo));   # reflection co-efficient\n\n# Result\nprint'Reflection Co-efficient = %3.1f\\n'%p, 'Charecteristic impedance = %d ohm' %Zo;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Reflection Co-efficient = 0.6\nCharecteristic impedance = 75 ohm\n"
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:66"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nZo      = 75;       # charecteristic impedance in ohm\nVref    = 100;      # reflected voltage\nPref    = 100;      # reflected power in watts\n\n# Calculations\nZl      = (Vref)**2 /float(Pref);       # load impedance\np       = (Zl - Zo)/float((Zl + Zo));   # reflection co-efficient\nPinc    = Pref/float(p);                 # incident power\nPobs    = Pinc - Pref            # power obsorbed\n\n# Result\nprint'Load Resistance = %d ohm\\n'%Zl,'Reflection Co-efficient = %3.3f\\n'%p,'incident power = %d watts\\n'%Pinc,'power obsorbed = %d watts'%Pobs;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Load Resistance = 100 ohm\nReflection Co-efficient = 0.143\nincident power = 700 watts\npower obsorbed = 600 watts\n"
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:67"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nc      = 3*10**8;        # velocity in m/s\nf      = 100*10**6       # operating frequency in hz\nZin    = 100;\nZl     = 25;\n\n# Calculations\n\nlamda  = c/float(f);            # wavelength in m\nLreq   = lamda/float(4);       # required length in m\nZo     = math.sqrt(Zin*Zl);  #charecteristic impedance in ohm\n\n# Result\nprint'Length of line required = %d cm\\n'%(Lreq*10**2),'Charecteristic impedance = %d ohm',%Zo;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Length of line required = 75 cm\nCharecteristic impedance = 50 ohm\n"
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:67"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n#Variable Declaration\n# in the first case when the line is lamda/2 long, the i/p impedance is same as the load resistance\nZl      = 300;      # load resistance in ohm\nZo      = 75;       # charecteristic impedance in ohm\n\n# calculations\n#Zi      = Zo*((Zl + iZotan\u03b2l)/float((Zo + iZltan\u03b2l));\n#        = Zo*(((Zl/tan\u03b2l) + iZo))/((Zl/tan\u03b2l) + iZo)))\n# for l = lamda/2 \u03b2l = (2* \u03c0/lamda)*(lamda/float(2)) =  \u03c0\n# therefore tan\u03b2l = 0 which gives Zi = Zl\n# in the second case when the operating frequency is halved, the wavelength is dou\u03b2led which means the same line is now lamda/4 long\n# for l = lamda/4 ,\u03b2l = (2* \u03c0/lamda)*(lamda/4) =  \u03c0/2\n# therefore tan\u03b2l = \u221e\n\nZi         = (Zo**2)/float(Zl);  # input impedance\n\n#Result\nprint'Input impedance = %3.2f ohm'%Zi;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Input impedance = 18.75 ohm\n"
+      }
+     ],
+     "prompt_number": 16
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:68"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\nf       = 100*10**6;             # operating frequency in Hz\nv       = 2*10**8 ;              # propagation velocity in m/s\nZo      = 300;                  # charecteristic impedance in ohm\nZin     = 300;                  # input impedance in ohm\nl       = 1;                    # length in m\nV       = 100;\n\n# Calculations\nlamda   = v/float(f);                   # wavelength in m\nif(lamda/float(2) == l):\n    Zl  = Zin;\n\nk       = (V*Zin)/float((Zin+Zl));\n#Vin   = k*cos(2*%pi*f*t)\n# since the line is lamda/2 long ,the signal undergoes a phase delay of  \u03b2l = (2*\u03c0)/lamda *(lamda/2) = \u03c0\n# Result\n\nprint 'Vin = %dcos(2\u03c0'%k,'%3.0et)'%f\nprint 'Vl  = %dcos(2\u03c0'%k,'%3.0et-\u03c0)'%f\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Vin = 50cos(2\u03c0 1e+08t)\nVl  = 50cos(2\u03c0 1e+08t-\u03c0)\n"
+      }
+     ],
+     "prompt_number": 30
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:68"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nVSWR    = 3;         # voltage standing wave ratio\nd       = 20*10**-2  # separation b/w 2 successive minimas\ner      = 2.25;      #dielectric constant\nv       = 3*10**8;   # velocity in m/s\n\n# Calculations\n# VSWR = (1 + p)/float((1 - p));\np       = (VSWR -1)/float((VSWR + 1));     # reflection co-efficient\nlamda   = 2*d;                      # wavelength of tx line\nlamda_fr= lamda*math.sqrt(er);           # free space wavelength\nf       = v/float(lamda_fr);               # operating frequency in Hz\n\n#Result\nprint'Magnitude of Reflection Co-efficient = %3.1f\\n'%p,'Frequency of Operation = %3.0f Mhz'%(f/10**6);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Magnitude of Reflection Co-efficient = 0.5\nFrequency of Operation = 500 Mhz\n"
+      }
+     ],
+     "prompt_number": 20
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 10,Page No:69"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\nC   = 30;           # per unit capacitance in pF/m\nVp  = 260;          # velocity of propagation in m/us\nf   = 500*10**6      # freq in Hz\nZl  = 50;           # terminating load impedance in ohm\n\n# calculations\nv   = Vp/float(10**-6);      # conversion from m/us to m/s\nC1  = C*10**-12      # conversion from pF/m to F/m\n# 1/math.sqrt(LC) = Vp\nL   = 1/float((v**2 * C1));  # per unit inductance\nZo  = math.sqrt(L/float(C1));     # charecteristic impedance in ohm\nlamda = v/float(f);          # wavelength\nb    = (2*math.pi)/lamda  # phase shift constant\np    = (Zl - Zo)/float((Zl + Zo));     # Reflection coefficient\n\n# Result\nprint'Per Unit inductance = %d nH/m\\n'%(L*10**9);\nprint'Charecteristic Impedance = %d ohm\\n'%Zo;\nprint'Phase shift Constant = %d rad/m\\n'%b;\nprint'Reflection co-efficient = %3.3f'%abs(p);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Per Unit inductance = 493 nH/m\n\nCharecteristic Impedance = 128 ohm\n\nPhase shift Constant = 12 rad/m\n\nReflection co-efficient = 0.439\n"
+      }
+     ],
+     "prompt_number": 62
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:77"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na   = 1.5*10**-2;        # width of waveguide \nb   = 1*10**-2           #narrow dimension of waveguide\ner  = 4;                 #dielectric constant\nf   = 8*10**9;           #frequency in Hz\nc   = 3*10**8;           #velocity in m/s\n\n#calculations\nlamda_c     = 2*a;      #cut-off wavelength for TE10 mode\nlamda       = c/f       #wavelength corresponding to given freq.\nlamda_d     = lamda/math.sqrt(er);   #wavelength when waveguide filled with dielectric\nif lamda_d < lamda_c :\n    print('8 Ghz frequency will pass through the guide');\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "8 Ghz frequency will pass through the guide\n"
+      }
+     ],
+     "prompt_number": 32
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 12,Page No:77"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "\n# Variable Declaration\na   = 4*10**-2;          # width of waveguide \nb   = 2*10**-2           # narrow dimension of waveguide\ner  = 4;                # dielectric constant\nc   = 3*10**8            # velocity in m/s\n\n# Calculations\nlamda_c     = 2*a;      # max cut-off wavelength\nfcmin       = c/lamda_c # min freq\nlamda_d     = lamda_c/math.sqrt(er);     # wavelength if we insert dielectric\nfc          = c/lamda_d        # min frequency in presence of dielectric\n\n# Result\nprint'Minimum Frequency that can be passed with dielectric in waveguide is %3.1f Ghz'%(fc/float(10**9));\n\n\n \n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Minimum Frequency that can be passed with dielectric in waveguide is 7.5 Ghz\n"
+      }
+     ],
+     "prompt_number": 33
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 13,Page No:78"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf   = 1*10**9;       # frequency in Hz\na   = 5*10**-2;      # wall separation\nc   = 3*10**8;       # velocity of EM wave in m/s\nm   = 1;            # for TE10\nn   = 0;            # for TE10\n\n# Calculations\n# lamda0   = 2/math.sqrt((m/a)**2 + (n/b)**2)\nlamda0      = (2*a)/m\nlamda_frspc = c/float(f);\nif lamda_frspc > lamda0:\n    print'1 Ghz signal cannot propagate in TE10 mode'\nelse:\n    print'1 Ghz signal can propagate in TE10 mode';\n\n    \n    \n    \n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "1 Ghz signal cannot propagate in TE10 mode\n"
+      }
+     ],
+     "prompt_number": 36
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 14,Page No:78"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na   = 30;            # width of waveguide\nb   = 20;           # narrow dimension of waveguide\nc   = 3*10**8;       # velocity of EM wave in m/s\nm   = 1;            # for TE10\nn   = 0;            # for TE10\n\n#Calculations\n#lamda0   = 2/math.sqrt((m/a)**2 + (n/b)**2)\nlamda0      = (2*a)/m;      # longest cut-off wavelength in dominant mode TE10\n\n# Result\nprint'longest cut-off wavelength = %d mm'%lamda0;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "longest cut-off wavelength = 60 mm\n"
+      }
+     ],
+     "prompt_number": 37
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 15,Page No:107"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na   = 4*10**-2;       # width of waveguide\nb   = 2*10**-2;       #narrow dimension of waveguide\nc   = 3*10**8;        # velocity of EM wave in m/s\nm1  = 1;              # for TE10\nm2  = 2;              # for TE20\nn   = 0;              # for TE10\n\n# Calculations\nlamda_c     = 2*a       # cutoff wavelength for TE10 mode\nf1          = c/lamda_c # frequency in Hz\n# the frequency range for single mode operation is the range of frequencies corresponding to the dominant mode and the second highest cutoff wavelength\nlamda_c_2   = 2/math.sqrt((m2/a)**2 + (n/b)**2)\nf2          = c/lamda_c_2;   # freq at second largest cutoff wavelength\n\n# Result\nprint'Therefore,single mode operating range = %3.2f Ghz'%(f1/float(10**9)),'to %3.1f Ghz\\n' %(f2/float(10**9));\nprint'Note: instead of 3.75,3.5 is printed in textbook';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Therefore,single mode operating range = 3.75 Ghz to 7.5 Ghz\n\nNote: instead of 3.75,3.5 is printed in textbook\n"
+      }
+     ],
+     "prompt_number": 39
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 16,Page No:108"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na   = 7.2;            # width of waveguide in cm\nb   = 3.4;            # narrow dimension of waveguide in cm\nc   = 3*10**10;       # free space velocity of EM wave in cm/s\nf   = 2.4*10**9;      #frequency in Hz\n\n#Calculation\nlamda   = c/f       # free space wavelength in cm\nlamda_c = 2*a       # cutoff wavelength in cm\nlamda_g = lamda/math.sqrt(1 - (lamda/lamda_c)**2); # guide wavelength in cm\nvp      = (lamda_g * c)/lamda                      # phase velocity in cm/s\nvg      = c**2/float(vp);                          # group velocity in cm/s\n\n# Result\nprint'Group velocity = %3.1e cm/s\\n'%vg, 'Phase Velocity = %3.1e cm/s'%vp;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Group velocity = 1.5e+10 cm/s\nPhase Velocity = 6.0e+10 cm/s\n"
+      }
+     ],
+     "prompt_number": 40
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 18,Page No:109"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data\n# let 'a' and 'b' be the broad and narrow dimensions of the rectangular guide and 'r' be internal radius of circular guide\n# Dominant mode in rectangular guide =TE10\n# cutoff wavelength = 2a\n# dominant mode in circular guide = TE11\n# cut-off wavelength = 2*pi*r/1.841  = 3.41r\n# for the two cut-off wavelengths to equal\n# 2a  = 3.41r\n# a = 1.705r\n# now area of cross section of rectangular guide = a*b\n# assuming a= 2b,which is very reasonable assumption ,we get \n# area of cross section of rectangular waveguide = a*a/2 = ((1.705^2)*r*r)/2 = 1.453r**2\n# area of cross-section of circular guide = pi*r*r = 3.14r**2\n# ratio of two cross sectional areas = (3.14r**2)/(1.453r**2) = 2.16\n# output\nprint'Circular guide is 2.16 times larger in cross section as compared to rectangular guide';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Circular guide is 2.16 times larger in cross section as compared to rectangular guide\n"
+      }
+     ],
+     "prompt_number": 41
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 19,Page No:110"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na   = 4*10**-2;      # width of waveguide\nb   = 2*10**-2;      # narrow dimension of waveguide\nc   = 3*10**8;      # velocity of EM wave in m/s\nf   = 5*10**9       # operating frequency in Hz\nm0  = 0;            # for TE01\nm1  = 1;            # for TE10 / TE11 /TM11\nn0  = 0;            # for TE10\nn1  = 1;            # for TE11 or TM11  \n\n# Calculations\nlamda        = c/f;                                # operating wavelength\nlamda_TE01   = 2/math.sqrt((m0/a)**2 + (n1/b)**2)  # cutoff wavelength for TE01\nlamda_TE10   = 2/math.sqrt((m1/a)**2 + (n0/b)**2)  # cutoff wavelength for TE10\nlamda_TE11   = 2/math.sqrt((m1/a)**2 + (n1/b)**2)       # cutoff wavelength for TE11 or TM11\n\n# Result\nif lamda_TE01 >lamda:\n    print'TE01 propagates in the given guide at the given operating frequency';\n    \nelif lamda_TE10 >lamda:\n    print'TE10 propagates in the given guide at the given operating frequency';\nelif lamda_TE11 >lamda:\n    print'TE11 propagates in the given guide at the given operating frequency';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "TE01 propagates in the given guide at the given operating frequency\n"
+      }
+     ],
+     "prompt_number": 40
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 20,Page No:110"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na   = 4*10**-2;      # width of waveguide\nb   = 2*10**-2;      # narrow dimension of waveguide\nc   = 3*10**8;       # velocity of EM wave in m/s\nd   = 4*10**-2;      # distance b/w field maxima and minima\n\n# Calculations\nlamda_c     = 2*a;      # cut-off wavelength in dominant mode\nlamda_g     = 4*d;      # guide wavelength\n# lamda_g  = lamda0/float((math.sqrt(1 -(lamda0/lamda_c)**2)))\nlamda0      = math.sqrt(((lamda_c * lamda_g)**2) / float((lamda_c**2 )+ (lamda_g**2)));\nf0          = c/float(lamda0);     # frequency of the wave\n\n# Result\nprint'Frequency of the wave = %3.3f Ghz'%(f0/float(10**9));\n\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Frequency of the wave = 4.193 Ghz\n"
+      }
+     ],
+     "prompt_number": 41
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 21,Page No:111"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na   = 6;      # width of waveguide in cm\nb   = 3;      # narrow dimension of waveguide in cm\nlamda = 4;    # operating wavelength in cm\nc   = 3*10**8;       # velocity of EM wave in cm/s\n\n# Calculations\nlamda_c  = 2*a;      # cut-off wavelength in dominant mode\nlamda_g  = lamda/(float((math.sqrt(1 - ((lamda/float(lamda_c))**2))))); # guide wavelength\nVp       = (lamda_g/float(lamda))*c;\nb        = (2*math.pi)/float(lamda_g);     # phase shift constant\n\n#Result\nprint'Guide wavelength = %3.2f cm\\n'%lamda_g;\nprint'Phase velocity = %3.2e m/s\\n'%Vp;\nprint'Phase shift constant = %3.2f radians/cm'%b;   \n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Guide wavelength = 4.24 cm\n\nPhase velocity = 3.18e+08 m/s\n\nPhase shift constant = 1.48 radians/cm\n"
+      }
+     ],
+     "prompt_number": 73
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 22,Page No:111"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# variable Declaration\ner      = 9;          # relative permittivity\nc       = 3*10**10;   # velocity of EM wave in free space\nf       = 2*10**9;    # operating frequency in Ghz\na       = 7;          # width of waveguide in cm\nb       = 3.5;        # narrow dimension of waveguide in cm\n\n# calculations\nlamda_c  = 2*a;                 # cut-off wavelength in dominant mode\nfc       = c/float(lamda_c );           # cut-off frequency in Hz\nlamda    = c/float((math.sqrt(er)*f));       # operating wavelength\nlamda_g  = lamda/(math.sqrt(1 - ((lamda/float(lamda_c))**2))); # guide wavelength\nVp       = (lamda_g/float(lamda))*c\n\n# Result\nprint'Cut-off frequency = %3.3f Ghz\\n'%(fc/float(10**9));\nprint'Phase velocity = %3.2e m/s\\n'%(Vp/float(10**2));\nprint'Guide wavelength = %3.2f cm'%lamda_g;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Cut-off frequency = 2.143 Ghz\n\nPhase velocity = 3.21e+08 m/s\n\nGuide wavelength = 5.35 cm\n"
+      }
+     ],
+     "prompt_number": 80
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_4.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_4.ipynb
new file mode 100644
index 00000000..5a366165
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_4.ipynb
@@ -0,0 +1,251 @@
+{
+ "metadata": {
+  "name": "CHAPTER 4"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 4:Microwave Components"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:167"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPi      = 10;           # Input power in mW\nCF      = 20;           # coupling factor in dB\n\n# calculations\n# CF(db)   = 10*math.log(Pi/Pc)\nPc      = Pi/(float((10**(CF/float(10)))));# antilog conversion and coupling power\n\n# Result\nprint'Coupled Power = %d uW'%(Pc*10**3);\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Coupled Power = 100 uW\n"
+      }
+     ],
+     "prompt_number": 30
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:167"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPi      = 10;           # Input power in mW\nIL      = 0.4;          # insertion loss in dB\n\n# calculations\n# ILdb   = 10log(Pi/Po)\nPo      = Pi/float((10**(IL/10))) # antilog conversion and coupling power\n\n# Result\nprint'Power available at the straight through port output = %3.3f mW'%Po;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Power available at the straight through port output = 9.120 mW\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:168"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nCF      = 20;       # Coupling factor in dB\nI       = 50;       # Isolation in dB\nPc      = 100*10**-6; # coupling power in W\n\n# calculations\n# D    = 10log(Pc/Piso)\nD       = I - CF;           # Directivity in dB\nPiso    = Pc/float((10**(D/float(10))))  # antilog conversion and coupling power\n\n# Result\nprint'Directivity = %d dB\\n'%D,'Power at isolated port = %d nW'%(Piso*10**9);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Directivity = 30 dB\nPower at isolated port = 100 nW\n"
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page no:168"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nCF      = 20;           # coupling factor in dB\nD       = 30;           # Directivity in dB\nPin     = 10;           # input power in dBm\n\n# Calculations\n# 10logPi = Pin\nPi      = 10**(Pin/10);   # power in mW\nI       = D + CF          # isolation in dB\nPc      = Pin - CF;\nPcwatts = 10**(Pc/10)     # power at coupled port in mW\nPiso    = Pin - I\nPisowatts = 10**(Piso/10) # Power at isolated port in mW\nPo      = Pi -(Pcwatts + Pisowatts);    # power at o/p port in mW\n\n# Result\nprint'Power Available at the output port = %3.5f mW'%Po;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Power Available at the output port = 9.89990 mW\n"
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:169"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\n\nPi      = 5*10**-3;            # Input power in W\nCF      = 10;                  # coupling factor\nPiso    = 10*10**-6            # power at isolated port in w\n\n# calculations\n# CF   = 10log(Pi/Pc)\nPc      = Pi/(10**(CF/10))  # antilog conversion and coupling power\n# D    = 10log(Pc/Piso)    # Directivity\nD       = 10*math.log10(Pc/Piso)\n\n# Result\nprint'Directivity = %3.0f dB\\n'%D;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Directivity =  17 dB\n\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:169"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\na       = 2;        # width in cm\nb       = 1;        # Height in cm\nd       = 3;        # length in cm\nc       = 3*10**10;  # vel in free space in cm/s\n# For TE101 mode\nm       = 1\nn       = 0;\np       = 1;\n\n# Calculations\nfo      = (c/float(2))*math.sqrt((m/float(a)**2)+ ((n/float(b))**2 )+ (p/float(d))**2);\n\n# Output\nprint'Resonant Frequency = %d Ghz' %(fo/float(10**9));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Resonant Frequency = 9 Ghz\n"
+      }
+     ],
+     "prompt_number": 35
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:170"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\nfo      = 10;       # resonant freq in Ghz\n# output\nprint'The Resonant frequency for a TM mode in a rectangular cavity resonator for a given integral\\n';\nprint'values of m,n and p is same as that of a TE mode for same values of m,n and p\\n';\nprint'Therefore,TM111 mode resonant frequency = %d Ghz'%fo;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "The Resonant frequency for a TM mode in a rectangular cavity resonator for a given integral\n\nvalues of m,n and p is same as that of a TE mode for same values of m,n and p\n\nTherefore,TM111 mode resonant frequency = 10 Ghz\n"
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:170"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na       = 4;        # width in cm\nb       = 2;        # Height in cm\nc       = 3*10**10;  # vel in free space in cm/s\nfo      = 6*10**9;    # resonator frequency in Ghz\n# For TE101 mode\nm       = 1\nn       = 0;\np       = 1;\n\n# Calculations\n#fo      = (c/float(2))*math.sqrt((m/float(a)**2 + (n/float(b)**2 + (p/float(d)**2);\nd       = math.sqrt(((p**2)/((((2*fo)/float(c))**2) - ((m/float(a))**2) -((n/float(b))**2))));\n\n# Result\nprint'Length of cavity resonator = %3.1f cm'%d;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Length of cavity resonator = 3.2 cm\n"
+      }
+     ],
+     "prompt_number": 40
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:170"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na       = 4;        # width in cm\nb       = 2;        # Height in cm\nc       = 3*10**10;  # vel in free space in cm/s\nfo      = 6*10**9;   # resonator frequency in Ghz\nd       = 3.2;      # length of cavity resonator in cm\n# For TE101 mode\nm       = 1\nn       = 0;\n\n# Calculations\nlamda_c = 2/(float(math.sqrt(((m/float(a))**2) + ((n/float(b))**2))));      # cut-off wavelength in m\nlamda   = c/float(fo);                             # operating wavelength in m\nlamda_g = lamda/(float(math.sqrt(1 - ((lamda/float(lamda_c))**2))));# guide wavelength in m\n\n# output\nprint'Length of resonator is %3.1f cm'%d,' and  guide wavelength is %3.1f cm'%(lamda_g);\nprint'\\nlength of resonator is half of guide wavelength';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Length of resonator is 3.2 cm  and  guide wavelength is 6.4 cm\n\nlength of resonator is half of guide wavelength\n"
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 10,Page No:171"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\ndi       = 8;        # internal diameter in cms\na        = 4;        # internal radius in cms\nfo      = 10*10**9;  # operating frequency in Ghz\nha01    = 2.405;    # Eigen value of bessel function\nc       = 3*10**10   # velocity of EM wave in cm/sec\n# For TM011 mode\nm       = 0\nn       = 1\np       = 1\n\n# Calculations\n#f0  = (c/2*pi)*sqrt((ha/a)**2 + (p*pi/d)**2)  operating frequency\nd     = (p*math.pi)/(math.sqrt((fo*2*math.pi/c)**2 - (ha01/a)**2))   #length of resonator\n\n# result\nprint'Length of resonator = %3.3f cm'%d;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Length of resonator = 1.566 cm\n"
+      }
+     ],
+     "prompt_number": 22
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:172"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\ndi       = 6;        #internal diameter in cms\nd        = 5;        #length in cm\na        = 4;        #internal radius in cms\nfo      = 10*10**9; #perating frequency in Ghz\nha01    = 2.405;    #Eigen value of bessel function\nha11    = 1.841;    #Eigen value of bessel function\nc       = 3*10**10   #velocity of EM wave in cm/sec\n#For TM011 mode and TE111 mode\nm0       = 0\nm1       = 1\nn1       = 1\np1       = 1\np2       = 2\n\n# Calculations\nf0  = (c/(2*math.pi))*math.sqrt((ha01/a)**2 + (p2*math.pi/d)**2)     #resonant frequency for TM012 mode \nf01  = (c/(2*math.pi))*math.sqrt((ha11/a)**2 + (p1*math.pi/d)**2)        # resonant frequency for TE111 mode \n\n# Result\nprint'Resonant frequency for TM012 mode = %3.3f Ghz\\n'%(f0/float(10**9)), 'Resonant frequency for TM111 mode = %3.3f Ghz\\n'%(f01/float(10**9 ));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Resonant frequency for TM012 mode = 6.651 Ghz\nResonant frequency for TM111 mode = 3.719 Ghz\n\n"
+      }
+     ],
+     "prompt_number": 5
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_5.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_5.ipynb
new file mode 100644
index 00000000..10b4b167
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_5.ipynb
@@ -0,0 +1,188 @@
+{
+ "metadata": {
+  "name": "CHAPTER 5"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 5:Microwave Tubes"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:226"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nF     =  100*10**9;   #reflex klystron operating frequency\nn     =  3;         #integer corresponding to mode\n\n#Calculations\nT_c   =  (n+(3/float(4)))   #transit time in cycles\nT     =  T_c/float(F);      #transit time in seconds\n\n# Result\nprint'Transit Time of the electron in the repeller space is %3.1f ps'%(T/float(10**-12));\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Transit Time of the electron in the repeller space is 37.5 ps\n"
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:227"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nF     =  2*10**9;#reflex klystron operating frequency\nVr    =  2000;#Repeller voltage\nVa    =  500;#Accelarating voltage\nn     =  1;#integer corresponding to mode\ne     =  1.6*10**-19;#charge of electron\nm     =  9.1*10**-31;#mass of electron in kg\ns     =  2*10**-2;#space b/w exit of gap and repeller electrode\ndVr1  = 2;    #(change in Vr in percentage\n\n#Calculations\ndVr   = dVr1*Vr/100;     #conversion from percentage to decimal\n#dVr/df = ((2*math.pi*s)/((2*math.pi*n)-pi/2))*sqrt(8*m*Va/e));\n#let df = dVr/((2*math.pi*s)/((2*math.pi*n)-pi/2))*sqrt(8*m*Va/e));\n\ndf       =  (dVr)/((2*math.pi*s)/((2*math.pi*n)-(math.pi/2))*math.sqrt(8*m*Va/e)); #change in freq as a fun of repeller voltage\n\n\n# Result\nprint'Change in frequency is %3.0f MHz'%(df/float(10**6));\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Change in frequency is  10 MHz\n"
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:228"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\n# let l   = dVr/Vr ; f  = df/f ; Vr/f  = R\nl     = 5;#percentage change in repeller voltage\nf     = 1;#percentage change in operating frequency\nR     = 1;#ratio of repeller voltage to operating frequency\nNR    = 1.5;#new ratio of repeller voltage to operating frequency in volts/MHz\ne     =  1.6*10**-19;#charge of electron\nm     =  9.1*10**-31;#mass of electron in kg\n\n# Calculations\n\n#dVr/df = ((2*math.pi*s)/((2*math.pi*n)-pi/2))*math.sqrt(8*m*Va/e));\n#((df/f)/(dVr/Vr)) = (Vr/f)*((2*math.pi*n)-pi/2)/(2*math.pi*s)*math.sqrt(e/(8*m*Va));\n#((df/f)/(dVr/Vr)) = K*(Vr/f);\n#where K = (((2*math.pi*n)-math.pi/2)/float((2*math.pi*s))*math.sqrt(e/float((8*m*Va)))\nK    = (f/float(l))*(1/float(R));\nPCF  = NR*K*l; #percentage change in frequency when new ratio (Vr/f)=1.5;\n\n# Result\nprint'Percentage Change in frequency is %3.2f percent'%PCF;\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Percentage Change in frequency is 1.50 percent\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:228"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nVa    = 40*10**3;      # Anode voltage of cross field amplifier\nIa    = 15;            # Anode current in Amp\nPin   = 40*10**3;      # input power in watts\nG     = 10;            # gain in dB\nn     = float(40)/100;        # overall efficiency converted from percentage to decimal\n\n\n# Calculations\nGain  = (1+(float(Pgen)/Pin))\nPgen  = (G-1)*Pin      # Generated power\nne    = (Pgen/float(Va*Ia)) # electronic efficiency \nnc    = n/(ne)         # circuit efficiency \nPout  = Pin+(Pgen*nc)  # output power\n\n# Result\nprint 'Electronic Efficiency is %3.2f' %ne\nprint 'Output power is %g KW' %(Pout/float(1000));",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Electronic Efficiency is 0.60\nOutput power is 280 KW\n"
+      }
+     ],
+     "prompt_number": 13
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:229"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nF     =  1*10**9;  #two cavity klystron operating frequency\nVa    =  2500;     #Accelarating voltage in volts\ne     =  1.6*10**-19;  #charge of electron\nm     =  9.1*10**-31;   #mass of electron in kg\ns     =  0.1*10**-2;    #input cavity space\n\n#Calculations\n\nu     = math.sqrt((2*e*Va)/m);   #velocity at which electron beam enters the gap\nT     = s/u ;  #Time spent in the gap\nf     = T*F;   #number of cycles\n\n# result\nprint'Number of cycles that elase during transit of beam through input gap is %3.3f cycle'%f;\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Number of cycles that elase during transit of beam through input gap is 0.034 cycle\n"
+      }
+     ],
+     "prompt_number": 14
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:230"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given Data\nN     = 8;   #no. of resonators\n\n#Calculations\nprint'\u03d5  = (2*\u03c0*n)/N \\n';  #phase difference\nprint'\u03d5   = (n*\u03c0)/4\\n';   #phase difference\nK   = N/2;                     #useful no. of nodes\n# Most dominant mode is the one for which phase differnce b/w adjacent resonators is \u03c0 radians\n# Therefore (n*\u03c0)/4 = \u03c0\nn = 4\n\n\n# Output\nprint'Number of possible modes of Resonance is %d\\n'%N;\nprint'Number of useful modes of Resonance is %d\\n'%K;\nprint'value of integer n for the most dominant mode is %d'%n;\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "\u03d5  = (2*\u03c0*n)/N \n\n\u03d5   = (n*\u03c0)/4\n\nNumber of possible modes of Resonance is 8\n\nNumber of useful modes of Resonance is 4\n\nvalue of integer n for the most dominant mode is 4\n"
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:230"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nVa    =  1200;  #Anode potential\nF     =  10*10**9;  #Operating frequency in Hz \nS     =  5*10**-2;  #spacing b/w 2 cavities\nGS    = 1*10**-3;   #gap spacing in either cavity\ne     =  1.6*10**-19;  #charge of electron\nm     =  9.1*10**-31;  #mass of electron in kg\n\n# Calculations\n# Condition of maximum output is (V1/Vo)max  =  (3.68)/((2*pi*n)-(pi/2);\n# (2*pi*n)-(pi/2) = Transit angle b/w two cavities\n# V1  = Peak amplitude of RF i/p\n# Vo  = accelarating potential\n\nVo    = math.sqrt(2*e*Va/m);  #velocity of the electrons \nT     = S/Vo;            #Transit time b/w the cavities\nTA    = 2*math.pi*F*T;      #transit angle in radians\nV1    = (3.68*Va)/TA;\n\n# Result\nprint'Required Peak Amplitude of i/p RF signal is %3.2f volts'%V1;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Required Peak Amplitude of i/p RF signal is 28.88 volts\n"
+      }
+     ],
+     "prompt_number": 16
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:231"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given Data\nR       = 10;            # circumference to pitch ratio\ne       = 1.6*10**-19;   # charge of electron\nm       = 9.1*10**-31;   # mass of electron in Kg\nc       = 3*10**8;       # vel. of EM waves in m/s\n\n# Calculations\nVp      = c/float(R);           # axial phase velocity = free space vel*(pitch/circumference) \nVa      = (Vp**2 * m)/float((2*e));\n\n# Output\nprint'Anode Voltage = %3.2f kV' %(Va/float(1000));\nprint'In practice,the electron beam velocity is kept slightly greater than the axial phase velocity of RF signal';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Anode Voltage = 2.56 kV\nIn practice,the electron beam velocity is kept slightly greater than the axial phase velocity of RF signal\n"
+      }
+     ],
+     "prompt_number": 17
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_6.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_6.ipynb
new file mode 100644
index 00000000..9b61dbf4
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_6.ipynb
@@ -0,0 +1,440 @@
+{
+ "metadata": {
+  "name": "CHAPTER 6"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 6:Semiconductor Microwave Devices"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:292"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math \n\n# Variable Declaration\ngs      = 0.0025;       # output conductance in mho\ngl      = 0.0025;       # load conductance\nr       = -250;         # negative resistance of microwave device\n\n# calculations\n\n#  P1  = Vl**2 *gl          # power that is transferred to load\n#  P   = Vl**2 *gs          # source is matched to load\n#  P   = [Is/(gl+gs)]**2 *gs\n#      = ((Is**2)/(4*gs**2))*gs \n#      = (Is**2)/(4*gl)\n#  P2  = Vl**2 *gl          # Load power\n#      = [Is/(gs+gl-g)]**2 *gl\n#      = (Is**2 *gl)/(2gl - g)**2\n# P2/P1 = ((Is**2 *gl)/(2gl - g)**2)*(4*gl)/(Is**2)\n#       = (4*gl**2)/(2gl - g)**2;\n#       = (4*gl**2)/(4gl**2 + g(g-4gl))\n# For P2/P1 > 1 , 4gl > g so that denominator is less than numerator \ng       = 1/float(r);\n# let k = P2/P1\nk       = (4*gl*gl)/((2*gs)+ g)**2\n\n# Result\nprint'Power gain = %d'%k;\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Power gain = 25\n"
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:293"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n\n# Variable Declaration\nRl      = 500;      # load resistance\n\n# Calculations\ngl      = 1/float(Rl);     # load conductance\ngmax    = 4*gl;     # max negative diff. conductance\n\n# Result\nprint'gmax = %3.3f mho'%gmax;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "gmax = 0.008 mho\n"
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:293"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nL       = 10*10**-6;     # width of N-region\nVs      = 10**5;          # saturated vel. of carriers\n\n# Calculations\nfo      = (3*Vs)/(4*L);     # oscillation frequency\n\n# Result\nprint'Operational frequency = %3.1f Ghz\\n'%(fo/float(10**9));\nprint'Note: In textbook it is wrongly printed as 6.5 Ghz';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Operational frequency = 7.5 Ghz\n\nNote: In textbook it is wrongly printed as 6.5 Ghz\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:294"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nL       = 10**-6;        # gate length\nVs      = 10**5;         # saturation velocity in m/s\n\n# calculations\nfT      = Vs/(2*math.pi*L); # cut-off freq.\n\n# Result\nprint'Unity gain cut-off frequency = %3.0f Ghz'%(fT/float(10**9));",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Unity gain cut-off frequency =  16 Ghz\n"
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page no:294"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 10*10**9;      # oscillating freq. of Gunn diode\nVs      = 10**5;          # saturation carrier velocity in m/s\n\n# calculations\nL       = Vs/float(f);         # length of active layer\n\n# Result\nprint'Length of active layer = %3.0f \u00b5m'%(L/float(10**-6));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Length of active layer =  10 \u00b5m\n"
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:294"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 10*10**9;       # oscillating freq. of Gunn diode\nVs      = 10**5;          # saturation carrier velocity in m/s\ner      = 13;             # relative permitivity\nu       = 100*10**-4;     # mobility in m^2/V-s\neo      = 8.85*10**-12;  # permitivity in F/m\ne       = 1.6*10**-19;   # charge of electron\n\n# Calculations\nL       = Vs/float(f);         # length of active layer\nno      = (eo*er*Vs)/float((L*e*u));  # doping concentration\n\n# Result\nprint'Doping Concentration no >> %3.2g /m**3'%no;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Doping Concentration no >> 7.2e+20 /m**3\n"
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:295"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Given data\nfo      = 40*10**9;     # oscillating freq. of Gunn diode\nno      = 10**15;       # doping concentration\nup      = 8000;         # mobility in positive conductance region\ner      = 13;           # relative permitivity\num      = 100;          # mobility in m^2/V-s\neo      = 8.85*10**-14;  # permitivity in F/cm\ne       = 1.6*10**-19;   # charge of electron\n\n# Calculations\n# (eo*er)/(e*up) << no/fo < (eo*er)/(e*um)  // condition to be satisfied\n# let k = (eo*er)/(e*up) , l = (eo*er)/(e*um) , p = no/fo\np       = no/fo\nk       = (eo*er)/(e*up)\nl       = (eo*er)/(e*um)\nif k<p:\n    if p<l:\n        print'Necessary Condition satisfied';\n    \n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Necessary Condition satisfied\n"
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:295"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nn       = 10**15;        # doping concentration in /cm^3\nu       = 8500;         # mobility in  m^2/V-s\ner      = 13;           # relative permitivity\neo      = 8.85*10**-14;  # permitivity in F/cm\ne       = 1.6*10**-19;   # charge of electron\n\n# Calculations\nTd      = (eo*er)/float((n*u*e));      # Dielectric relaxation time\n\n# Output\nprint'Dielectric relaxation time = %3.3f ps'%(Td*10**12);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Dielectric relaxation time = 0.846 ps\n"
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:296"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 20*10**9;      # oscillating freq. of Gunn device\nVs      = 10**5;         # saturation carrier velocity in m/s\n\n# Calculations\nL       = Vs/float(f);          # length of device\n\n# Result\nprint'length of device = %d \u00b5m'%(L*10**6);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "length of device = 5 \u00b5m\n"
+      }
+     ],
+     "prompt_number": 44
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 10,Page No:296"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data from graph\nup  = (2*10**7)/float(3000);                # mobility of diode in positive conductance region\nun  = (2*10**7 - 10**7)/float(((10-3)*10**3)); # mobility of diode in negative conductance region\n\n# Result\nprint'mobility of diode in positive conductance region = %d cm**2/(V-s)'%up;\nprint'mobility of diode in negative conductance region = %3.0f cm**2/(V-s)'%un;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "mobility of diode in positive conductance region = 6666 cm**2/(V-s)\nmobility of diode in negative conductance region = 1429 cm**2/(V-s)\n"
+      }
+     ],
+     "prompt_number": 46
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:297"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\ne       = 1.6*10**-19;   # charge of electron\nNd      = (10**15)*(10**6);    # mobility\nL       = 10*10**-6;      # active layer of Barritt diode\ner      = 12.5           # relative permitivity\neo      = 8.85*10**-12;   # permitivity in F/cm\n\n# calculations\nEx      = (e*Nd*L)/float((2*eo*er)) # electric field for Va = Vpt and x = L/2\nE       = Ex/float(10**2);           # electric field in v/cm\nVpt     = 10*10**-4*E\n\n# Result\nprint'Electric field E(x) = %3.0d KV/cm\\n'%(E/float(1000)),'Punch through voltage = %3.0f Volts'%Vpt;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Electric field E(x) =  72 KV/cm\nPunch through voltage =  72 Volts\n"
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 12,Page No:297"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nfT      = 10;       # ft specification of BJT\nf_a     = 2;        # operating freq in Ghz case a\nf_b     = 10;       # operating freq in Ghz case b\n\n# calculations\nhFE_a   = fT/float(f_a);     \nhFE_b   = fT/float(f_b);\n\n# Result\nprint'case a:\\n  hFE = %d\\n'%hFE_a,'case b:\\n  hFE = %d\\n'%hFE_b;\n    \n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "case a:\n  hFE = 5\ncase b:\n  hFE = 1\n\n"
+      }
+     ],
+     "prompt_number": 25
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 13,Page No:298"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nn       = 10**15;        # doping concentration in /cm^3\ner      = 15;            # relative permitivity\neo      = 8.85*10**-14;   # permitivity in F/cm\ne       = 1.6*10**-19;    # charge of electron\nsigma   = 133*10**-2;     # conductivity in ohm/cm\n\n# calculations\nTd      = (eo*er)/float(sigma);    # dielectric relaxation time constant\nu       = sigma/float((n*e)) ;     # mobility\n\n# Result\nprint'Dielectric relaxation time constant = %3.0f ps\\n'%(Td*10**12),'Carrier Mobility = %d cm**2/V-s'%u;\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Dielectric relaxation time constant =   1 ps\nCarrier Mobility = 8312 cm**2/V-s\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 14,Page No:298"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\ngm      = 50*10**-3;       # conductance in mho\ncgs     = 0.6*10**-12;     # gate to source capacitance\ncgd     = 0.015*10**-12;   # gate to drain capacitance\nRg      = 3;               # gate resistance in ohm\nRs      = 2;               # source resistance in ohm\nRi      = 2.5;             # intrinsic channel resistance\nRds     = 400;             # drain to source resistance\n\n# Calculations\nfT      = gm/(2*math.pi*cgs);   # device's fT\nt3      = 2*math.pi*Rg*cgd;\nr1      = (Rg+Rs+Ri)/Rds;\nfmax    = fT/(2*math.sqrt(r1 + (fT*t3)));    # max usable frequency\nif fmax>40*10**9:\n    print'Operation at 40 GHz is Theoretically possible\\n';\n\n# utput\nprint' fT = %3.1f Ghz\\n'%(fT/float(10**9)),' fmax = %3.1f'%(fmax/float(10**9));\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Operation at 40 GHz is Theoretically possible\n\n fT = 13.3 Ghz\n fmax = 44.2\n"
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 15,Page No:299"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf2      = 20;       # pump frequency in GHz\nf1      = 2;        # signal frequency in GHz\n\n# Calculations\nGp      = (f1+f2)/f1;       # power gain if parametric amp. operated as USB up-converter\nGp_dB   = 10*math.log10(Gp);     # power gain in dB\nGp_lsb  = (f2-f1)/f1;       # power gain if parametric amp. operated as LSB up-converter\nGp_db_lsb = 10*math.log10(Gp_lsb); # power gain in dB\n\n# Result\nprint'Power gain of parametric amplifier when operated as USB up-converter = %3.1f dB\\n'%Gp_dB ,'Power gain of parametric amplifier when operated as LSB up-converter = %3.2f dB'%Gp_db_lsb;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Power gain of parametric amplifier when operated as USB up-converter = 10.4 dB\nPower gain of parametric amplifier when operated as LSB up-converter = 9.54 dB\n"
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 16,Page No:300"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nh       = 6.63*10**-34;     # planck's constant in Joule-sec\nel      = 0.25;             # lower energy level in eV from energy level diag.\neh      = 1.5;              # higher energy level in eV from energy level diag.\ne       = 1.6*10**-19;      # charge of electron\nc       = 3*10**8;          # vel. of light in m/s\n\n# calculations\nhf      = (eh - el)*e;            # energy diff b/w two levels in J\nf       = hf/float(h);                   # frequency\nlamda   = c/float(f);                    # o/p laser wavelength in m\n\n# Result\nprint'Output laser wavelength = %3.0e m '%(lamda),'or %3.0f \u00b5m '%(lamda*10**6);\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Output laser wavelength = 1e-06 m  or   1 \u00b5m \n"
+      }
+     ],
+     "prompt_number": 55
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 17,Page No:312"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\np   = 0.1*10**-2;        # resistivity in ohm-m\nt   = 100*10**-6;        # thickness in m\nAR  = 10/1;              # aspect ratio\n\n# Calculations\nps  = p/float(t)\nR   = ps*AR;             # Resistance in ohm\n\n# Result\nprint'Resistance = %d \u03a9'%R;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Resistance = 100 \u03a9\n"
+      }
+     ],
+     "prompt_number": 31
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 18,Page No:312"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given data from fig\nR_a = 1000;      # resistance shown in fig a\nW1  = 0.15*10**-3  # width of geometry fig 6.72a\nL1  = 3*10**-3    # Length of geometry fig 6.72a\nW2  = 75*10**-6   # width of geometry fig 6.72b\nL2  = 1500*10**-6 # Length of geometry fig 6.72b\nt1  = 10*10**-6   # thickness of geometry fig 6.72a\nt2  = 20*10**-6   # thickness of geometry fig 6.72b\n\n#R1  = \u03c1s1*(L1/W1);  # resistor geometry of fig 6.72a\n#\u03c1s1 = (R1*W1)/L1; \nps1   = (R_a*W1)/L1;  # sheet resistivity of geometry of fig 6.72a\np     = ps1*t1;     # resistivity\nps2   = p/float(t2);       # sheet resistivity of geometry of fig 6.72b\nR2    = ps2*(L2/W2); # resistance of geometry of fig 6.72b\n\n# Result\nprint'For Geometry in Fig 6.72b\\n','sheet resistivity = %3.0f \u03a9/\u25a1\\n'%ps2,'Resistance = %d \u03a9'%R2;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "For Geometry in Fig 6.72b\nsheet resistivity =  25 \u03a9/\u25a1\nResistance = 500 \u03a9\n"
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 19,Page No:313"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nA       = 100*100*10**-12;       # Area of electrode\ner      = 9.6;                  # relative permitivity\nt       = 500*10**-6;            # substrate thickness\neo      = 8.85*10**-12;          # permitivity\n\n# Calculations\nC       = (eo*er*A)/float(t);            # capacitance in farad\n\n# Result\nprint'Capacitance = %3.2e pF'%(C*10**12);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Capacitance = 1.70e-03 pF\n"
+      }
+     ],
+     "prompt_number": 38
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 20,Page No:314"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nps      = 100;      # sheet resistivity\nL       = 1.04      # length\nW       = 0.02      # width\n\n# Calculations\nNOS     = L/W        # number of squares\nR       = ps * NOS   # resistance\n\n# Result\nprint'Resistance = %3.1f K\u03a9' %(R/float(1000));\n \n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Resistance = 5.2 K\u03a9\n"
+      }
+     ],
+     "prompt_number": 16
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_7.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_7.ipynb
new file mode 100644
index 00000000..8cd4bf8f
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_7.ipynb
@@ -0,0 +1,419 @@
+{
+ "metadata": {
+  "name": "CHAPTER 7"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 7:Antennas"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:332"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nLdipole    = 50;         # Length of dipole in cm\nc          = 3*10**10;   # velocity of EM wave in cm/s\nBW         = 10*10**6;   # bandwidth in Hz\n\n# Calculations\nlamda      = 2*Ldipole;     # wavelength in cm\nfo         = c/lamda;       # operating frequency in Hz\nQ          = fo/BW;          # quality factor\n\n# Result\nprint'Q = %d'%Q;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Q = 30\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:332"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nRr      = 72;       # Radiation resistance in ohms\nRl      = 8;        # Loss resistance in ohms\nAp      = 27;       # power gain \n\n# Calculations\nn       = Rr/float((Rr + Rl));     # radiation efficiency\nD       = Ap/float(n);             # Directivity\nD_dB    = 10*math.log10(D);      # directivity in dB\n\n# Result\nprint'Directivity = %3.2f dB'%D_dB;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Directivity = 14.77 dB\n"
+      }
+     ],
+     "prompt_number": 3
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:333"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nAZ_BW      = 0.5;      # beamwidth in degrees\nE_BW       = 0.5;      # beamwidth in degrees\nlamda      = 3*10**-2; # radar emission wavelength\n\n# Calculations\n\nAZ_BW_r    = AZ_BW*math.pi/float(180);     # azimuth beamwidth in radians\nE_BW_r     = E_BW*math.pi/float(180);      # elevation beamwidth in radians\nG          = (4*math.pi)/float((AZ_BW_r *E_BW_r ))     # antenna gain\nG_db       = 10*math.log10(G);        # gain in dB\nA          = (G*lamda*lamda)/float((4*math.pi));   # antenna aperture\n\n# Output\nprint'Gain of Antenna = %3.2f dB\\n'%G_db,'Antenna Aperture = %3.3f m'%A;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Gain of Antenna = 52.18 dB\nAntenna Aperture = 11.818 m\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:333"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nn_az      = 0.5;        #length efficiency in azimuth direction\nn_el      = 0.7;        #length efficiency in elevation direction\nA         = 10;         # area in square mts\n\n# Calculations\nn         = n_az * n_el;    # aperture efficiency\nAe        = n*A;            # Effective aperture\n\n# Output\nprint'Effective aperture of the antenna = %3.1f sq.m'%Ae;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Effective aperture of the antenna = 3.5 sq.m\n"
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:333"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPtot        = 100;      # certain antenna radiating power\nPtot_iso    = 10*10**3;  # isotropic antenna radiating power\n\n# Calculations\nD           = 10*math.log10(Ptot_iso/Ptot);  # Directivity of antenna\n\n# Output\nprint'Directivity of antenna = %d dB'%D;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Directivity of antenna = 20 dB\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:334"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nD       = 3;        # diameter of the antenna in m\nnl      = 0.7;      # length efficiency\nnr      = 0.9;      # radiation efficiency\nf       = 10*10**9;  # antenna operating freq.\nc       = 3*10**8;   # vel of EM waves in m/s\n\n# calculations\nde     = D*(nl)  # Effective diameter\nlamda   = c/float(f);      # wavelength in m\nBeam_w  = lamda/de # beamwidth in radian\nBeam_w_d= Beam_w*180/math.pi;       # beam width in degree;\nn_a     = nl * nl;    # Aperture efficiency\nAA      = (math.pi*D*D)/4;  # actual area in sq m\nAe      = AA*n_a;       # Effective aperture\nG       = (4*math.pi*Ae)/float((lamda**2)); # Gain\nG_db    = 10*math.log10(G);\n\n# Output\nprint'Beam Width = %3.2f degrees\\n '%Beam_w_d;\nprint'Effective Aperture = %3.2fsq m\\n'%Ae;\nprint'Gain = %3.1f dB'%G_db;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Beam Width = 0.82 degrees\n \nEffective Aperture = 3.46sq m\n\nGain = 46.8 dB\n"
+      }
+     ],
+     "prompt_number": 4
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:334"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\n# given (lamda/10) wire dipole\n# Radiation resistance of short dipoles is Rr  = 790*(1/lamda)**2;\n# Rr   = 790*(lamda/(10*lamda))**2;\n# Rr   = 7.9;\nprint'Radiation resistance = 7.9 ohms';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Radiation resistance = 7.9 ohms\n"
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:334"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\na_l     = 6;        # Azimuth length in m\nn_a     = 0.7;      # Azimuth length efficiency\nn_e     = 0.5;      # elevation length efficiency\ne_l     = 4;        # elevation length in m\nw       = 6;        # width of antenna\nh       = 4;        # height of antenna \nlamda   = 3*10**-2;  # wavelength\n\n# Calculations\nEff_A_l = a_l*n_a;  # effective azimuth length\nEff_E_l = e_l*n_e;  # effective elevation length\nA       = w*h       # actual area\nn       = n_a*n_e;  # aperture efficiency\nAe      = A*n;      # effective aperture\nAz_BW   = lamda/float(Eff_A_l) # Azimuth beam width\nE_BW    = lamda/float(Eff_E_l)  # elevation beam width\nAz_BW_d = Az_BW*180/float(math.pi)  # rad to deg conv\nE_BW_d  = E_BW*180/float(math.pi);  # rad to deg conv\nG       = (4*math.pi*Ae)/float((lamda**2)); #Gain\nG_dB    = 10*math.log10(G);  # gain in dB\n\n# Result\nprint'Azimuth Beamwidth = %3.2f degrees'%Az_BW_d; \nprint'Elevation Beamwidth = %3.2f degrees'%E_BW_d; \nprint'Gain = %3.1f dB'%G_dB;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Azimuth Beamwidth = 0.41 degrees\nElevation Beamwidth = 0.86 degrees\nGain = 50.7 dB\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:335"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\nBeam_w_3db  = 0.4;\n\n# Calculations\nN2N_Beam_w  = 2*Beam_w_3db; # Null to Null beamwidth\n\n# output\nprint'Null to Null Beam width = degrees',N2N_Beam_w;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Null to Null Beam width = degrees 0.8\n"
+      }
+     ],
+     "prompt_number": 39
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 10,Page No:335"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# given data\nRSSR        = 20;   # Rx signal strength in horizontal polarised antenna when rx RHCP\n\n# Calculations\n# When incident polarisation is circularly polarised and the antenna is linearly polarised,there is a ploarisation loss of 3dB\nISS         = RSSR + 3;     \n# a\n# when the Rx polarisation is same as the antenna polarisation , the polarisation loss is zero\nRSS_HP      = ISS;      # rx signal strength for incident wave horizontally polarised\n# b\n# when the incident wave is vertically polarised ,the angle between the incident polarisation and the antenna polarisation is 90\n# polarisation loss = 20log(1/cos( \u03c6))\n#                   = 20log(1/cos90) = \u221e\nRSS_VP      = 0;        # rx signal strength for incident wave vertically polarised\n# c\n# When the incident wave is LHCP and the antenna polarisation is linear ,there will be a 3dB polarisation loss and the \n# Rx signal strength therefore will be 20 dB only\nRSS_LHCP    = RSSR;      # rx signal strength for incident wave Left hand circularly polarised\n# d\n# The angle between the incident wave polarisation and the antenna polarisation is 60 degrees\nphi         = 60;                               # rx wave polarisation angle with horizontal\nPL          = 20*math.log10(1/float(math.cos(60*math.pi/float(180))));      # polarisation loss in dB\nRSS_Pangle  = ISS - PL;\n# Result\nprint'Received signal strength if incident wave horizontally polarised = %d dB'%RSS_HP;\nprint'Received signal strength if incident wave vertically polarised = %d dB'%RSS_VP;\nprint'Received signal strength if incident wave Left hand circularly polarised is %d dB'%RSS_LHCP;\nprint'Received signal strength if Received wave polarisation making 60deg angle with horizontal is %3.0f dB'%RSS_Pangle;\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Received signal strength if incident wave horizontally polarised = 23 dB\nReceived signal strength if incident wave vertically polarised = 0 dB\nReceived signal strength if incident wave Left hand circularly polarised is 20 dB\nReceived signal strength if Received wave polarisation making 60deg angle with horizontal is  17 dB\n"
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:337"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 300*10**6;     # operating frequency in Hz\nc       = 3*10**10;      # velocity of EM wave in cm/s\n\n# Calculations\nlamda   = c/float(f);          # wavelength in cm\n# Physical length of antenna is made 5% shorter than desired length as per rule of thumb\nl       = lamda/float(2);      # length of halfwave dipole\nlphy    = l-(5/float(100))*l;  # as per rule of thumb\n\n# Output\nprint'Length of a half wave dipole to be cut = %3.1f cm'%lphy;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Length of a half wave dipole to be cut = 47.5 cm\n"
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 12,Page No:342"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nZi      = 72;       # input impedance in ohms\n# A    = 1.5a      # area of cross section in sq.cm\n# Zif  = Zi*[(sum of areas of cross section of various components)/(Area of cross section of the driven element )]**2;\n# Zif  = 72*((a + 1.5a)/a)**2;\n# Zif  = 72*(2.5*a/a)**2;\nZif     = 72*(2.5)**2;\n\nprint'Input impedance for a folded dipole = %d \u03a9'%Zif;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Input impedance for a folded dipole = 450 \u03a9\n"
+      }
+     ],
+     "prompt_number": 25
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 13,Page No:342"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\nf       = 60*10**6;      # frequency in Hz\nc       = 3*10**8;      # velocity of EM wave in m/s\n\n# Calculations\nlamda   = c/float(f);          # wavelength in m\nl_dipole= lamda/float(2);      # length of diplole\n# Physical length of antenna is made 5% shorter than desired length as per rule of thumb\nL       = l_dipole - (5/float(100))*l_dipole;  # actual physical length\nL_D     = L - (4/float(100))*L;                # length of director\nL_R     = L + (4/float(100))*L;                # length of reflector\nDDS     = 0.12*lamda;                   # director dipole spacing\nRDS     = 0.2*lamda;                    # Reflector dipole spacing\n\n# Output\nprint'Length of dipole = %3.3f m'%L;\nprint'length of Director = %3.2f m'%L_D;\nprint'length of Reflector = %3.2f m'%L_R;\nprint'director dipole spacing = %3.1f m'%DDS;\nprint'Reflector dipole spacing = %3.1f m'%RDS;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Length of dipole = 2.375 m\nlength of Director = 2.28 m\nlength of Reflector = 2.47 m\ndirector dipole spacing = 0.6 m\nReflector dipole spacing = 1.0 m\n"
+      }
+     ],
+     "prompt_number": 14
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 14,Page No:352"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\nD       = 2;        # Mouth diameter in m\nf       = 2;        # focal length in m\nbw3db   = 90/float(100);   # beamwidth of antenna chosen to be 90% of angle subtended by feed\n\n# Calculations\ntheta   = 4*math.atan(1/float((4*f/float(D))));    # angle subtended by the focal point feed at edges of reflector\ntheta_d = theta*180/float(math.pi);\nBeam_w_3dB = bw3db*theta_d;       # 3 dB beam width\nNNBW    = 2*(Beam_w_3dB );\n\n# Output\nprint '3 dB Beamwidth = %3.1f\u00b0'%Beam_w_3dB,' Null-to-Null beam width = %3.2f\u00b0'%(NNBW);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "3 dB Beamwidth = 50.5\u00b0  Null-to-Null beam width = 101.06\u00b0\n"
+      }
+     ],
+     "prompt_number": 17
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 15,Page No:352"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable DECLARATION\nf       = 3;        # focal length in m\nfpos    = 1.5;      # feed is placed 1.5m from pt of intersection os sec.reflector and antenna axis\n\n# Calculation\nf_hyp   = f-fpos;   # focal length of hyperboloid from figure;\n\n# Result\nprint'focal length of hyperboloid = %3.1f m'%f_hyp;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "focal length of hyperboloid = 1.5 m\n"
+      }
+     ],
+     "prompt_number": 21
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 16,Page No:353"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nD       = 3;        # Mouth diameter in m\n#f       = 2;      # focal length in m\nbw3db   = 63;       # 3dB beam width\nk       = 0.9;      # beam width is k times subtended angle\n\n# Calculations\ntheta   = bw3db/k;  # subtended angle\ntheta_r = theta\n#theta   = 4*atan(1/(4*f/D));\nf       = D/(4*math.tan((theta_r/4)*(math.pi/180)));\n\n# Result\nprint'Distance of feed from the point of intersection of antenna axis and the reflector surface = %3.2f m'%f;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Distance of feed from the point of intersection of antenna axis and the reflector surface = 2.38 m\n"
+      }
+     ],
+     "prompt_number": 42
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 17,Page No:365"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nc       = 3*10**8;       # velocity of EM waves in m/s\nf       = 2.5*10**9;     # operating frequency in Ghz\nS       = 10*10**-2;     # inter element spacing\ntheta   = 10;            # steering angle \n\n# Calculations\nlamda   = c/f          # Wavelength in m\nphi     = (360*(S/lamda))*math.sin(theta*(math.pi/180))\nphi1    = 0*phi        # phase angle for element 1\nphi2    = 1*phi        # phase angle for element 2\nphi3    = 2*phi        # phase angle for element 3\nphi4    = 3*phi        # phase angle for element 4\nphi5    = 4*phi        # phase angle for element 5\n\n# Result\nprint'Phase angles for elements 1,2,3,4,5 are %d\u00b0'%phi1, '%d\u00b0'%phi2,'%d\u00b0' %phi3,'%d\u00b0' %phi4,'%d\u00b0' %phi5\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Phase angles for elements 1,2,3,4,5 are 0\u00b0 52\u00b0 104\u00b0 156\u00b0 208\u00b0\n"
+      }
+     ],
+     "prompt_number": 36
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 18,Page No:365"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Data is taken from Example 17. The beam steers towards left of the axis with all parameters remaining in Ex 17 are same\nc       = 3*10**8;       # velocity of EM waves in m/s\nf       = 2.5*10**9;     # operating frequency in Ghz\nS       = 10*10**-2;     # inter element spacing\ntheta   = -10;          # steering angle \n\n# Calculations\nlamda   = c/f          # Wavelength in m\nphi     = (360*S/lamda)*math.sin(theta*math.pi/180)\nphi1    = 0*phi        # phase angle for element 1\nphi2    = 1*phi        # phase angle for element 2\nphi3    = 2*phi        # phase angle for element 3\nphi4    = 3*phi        # phase angle for element 4\nphi5    = 4*phi        # phase angle for element 5\n\n# Output\nprint'Phase angles for elements 1,2,3,4,5 are %d\u00b0'%phi1, '%d\u00b0'%phi2,'%d\u00b0' %phi3,'%d\u00b0' %phi4,'%d\u00b0' %phi5\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Phase angles for elements 1,2,3,4,5 are 0\u00b0 -52\u00b0 -104\u00b0 -156\u00b0 -208\u00b0\n"
+      }
+     ],
+     "prompt_number": 35
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 19,Page No:365"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# given data\nS       = 5*10**-2;      # inter spacing distance\nlamda   = 6*10**-2;      # operating wavelength in cms\nphi_Az   = 25            # angle in azimuth direction\nphi_E    = 35            # angle in Elevation direction\n\n# Calculations\ntheta_Az  = math.asin((lamda*phi_Az)/(360*S))\ntheta_E   = math.asin((lamda*phi_E)/(360*S))\nTheta_Az  = theta_Az*(180/math.pi)\nTheta_E   = theta_E*(180/math.pi)\n\n# Output\nprint'Steering angle in Azimuth = %3.1f\u00b0'%Theta_Az\nprint 'Steering angle in Elevation = %3.1f\u00b0'%Theta_E;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Steering angle in Azimuth = 4.8\u00b0\nSteering angle in Elevation = 6.7\u00b0\n"
+      }
+     ],
+     "prompt_number": 39
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_9.ipynb b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_9.ipynb
new file mode 100644
index 00000000..126fd365
--- /dev/null
+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/CHAPTER_9.ipynb
@@ -0,0 +1,377 @@
+{
+ "metadata": {
+  "name": "CHAPTER 9"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": "Chapter 9:Radar Fundamentals"
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 1,Page No:449"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n#Variable Declaration\nPRF     = 1000;         #Pulse repetitive frequency in Hz\nt       = 0.15*10**-3; #Round propagation time in s\nc       = 3*10**8;     #velocity of EM waves in m/s\n#calculations\nR       = (c*t)/float(2);      #Range\nRunamb  = c/float((2*PRF));     #Max unambiguous range\n\n#Result\nprint'Target Range = %3.1f Km' %(R/float(1000));\nprint'Maximum Unambiguous range = %d Km'%(Runamb/float(1000));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Target Range = 22.5 Km\nMaximum Unambiguous range = 150 Km\n"
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 2,Page No:450"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n#Variable Declaration\nf       = 10*10**9;      # radar Tx frequency\nc       = 3*10**8;       # velocity of EM waves in m/s\nV       = 108;          # vel of car in kmph\n\n# Calculations\nlamda   = c/float(f);          # wavelength in m\nVr      = V*(5/float(18));     # vel of car in m/s\nfd      = (2*Vr)/float(lamda);  # Doppler shift in Hz\nfr      = f + fd        # received freq \nfr_away = f-fd          # Rx frequency if the car is moving away from radar\n\n# Result\nprint'Doppler Shift = %d Khz'%(fd/float(1000));\nprint'Frequency of Received signal = %3.6f Ghz'%(fr/float(10**9));\nprint'Received Frequency if car is moving away from radar = %3.6f Ghz'%(fr_away/float(10**9));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Doppler Shift = 2 Khz\nFrequency of Received signal = 10.000002 Ghz\nReceived Frequency if car is moving away from radar = 9.999998 Ghz\n"
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 3,Page No:450"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n#Variable Declaration\nf       = 10*10**9;      # radar Tx frequency\nPRF     = 2000;          # Pulse repetitive frequency in Hz\nVr      = 0.5;           # radial vel in Mach\nc       = 3*10**8;        # velocity of EM waves in m/s\nvs      = 330;           # velocity of sound in m/s\n\n# Calculations\nlamda           = c/float(f);          # wavelength in m\nmax_unamb_fd    = PRF/2;        # maximum unambiguous doppler shift\nVrunamb         = (lamda*max_unamb_fd)/2; # doppler shift\nVaircraft       = 0.5*vs;       # Converting from Mach to m/s\nfd_desired      = (2*Vaircraft)/lamda;\nPRF_desired     = 2*fd_desired; # desired PRF\n\n# Output\nif  Vrunamb < Vaircraft:\n    print'The radar is not capable of determining unambiguously the velocity of the approaching aircraft\\n';\n\nprint'Desired Pulse Repetition Rate = %d Khz'%(PRF_desired/1000);\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "The radar is not capable of determining unambiguously the velocity of the approaching aircraft\n\nDesired Pulse Repetition Rate = 22 Khz\n"
+      }
+     ],
+     "prompt_number": 5
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 4,Page No:450"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given Data\nPW_tx   = 10**-6;            # Transmitted pulse width\nRx_PW   = 10**-6;            # Received pulse width        \nc       = 3*10**8;           # velocity of EM waves in m/s\n\n# Calculations\nRR      = (c*Rx_PW)/float(2);      # Range Resolution in m\n\n# output\nprint'This Radar can resolve upto an inter target separation in range of %d m\\nTherefore,given radar will be able to resolve the targets'%RR;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "This Radar can resolve upto an inter target separation in range of 150 m\nTherefore,given radar will be able to resolve the targets\n"
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 5,Page No:451"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n#Variable Declaration\nCRR     = 100;      # Cross range resolution in m\nR       = 3000;     # radial range\n\n# Calculations\n# CRR  = (R*theta3)*(math.pi/180);\ntheta3  = (180*CRR)/(math.pi*R)         # 3 dB beamwidth\n\n# Result\nprint'3 dB beamwidth = %3.2f\u00b0'%theta3;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "3 dB beamwidth = 1.91\u00b0\n"
+      }
+     ],
+     "prompt_number": 6
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 6,Page No:451"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n#Variable Declaration\nVs      = 330;          # velocity of sound in m/s\nNM      = 1.85*(5/float(18))   # 1NM equivalent in m/s\nV1      = 0.5;          # velocity of first aircraft in mach\nV2      = 400;          # velocity of second aircraft in NM/hr\ntheta   = 30;           # angle with radial axis in degrees\nlamda   = 3*10**-2;      # wavelength in m\n\n# Calculations\nv1      = V1*Vs         # velocity of first aircraft in m/s\nfd1     = (2*v1)/float(lamda); # doppler freq.\nv2      = V2*NM*(math.cos(30*(math.pi/180)));  # velocity of second aircraft in m/s\nfd2     = (2*v2)/float(lamda);  # doppler freq\ndd      = fd2 - fd1;    # doppler difference\nTl      = 1/float(dd);         # look time in s\n\n# Result\nprint'Required minimum look time = %3.2f ms'%(Tl/float(10**-3));\nprint'\\nNote: Cos(30) value is taken as 0.5 in textbook';\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Required minimum look time = 1.15 ms\n\nNote: Cos(30) value is taken as 0.5 in textbook\n"
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 7,Page No:451"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given Data\n# Rmax     = [1000000/(12.4*PRF)]NM\n#          = [1000000*t/12.4]NM\nprint'The Numerator represents round trip propagation time in us\\n';\nprint'Therefore, number 12.4 represents the units microseconds per nautical miles\\n';\nprint'In other words, this means that the round propagation time for one nautical mile is 12.4 us which is equivalent to 6.66us for 1km range'\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "The Numerator represents round trip propagation time in us\n\nTherefore, number 12.4 represents the units microseconds per nautical miles\n\nIn other words, this means that the round propagation time for one nautical mile is 12.4 us which is equivalent to 6.66us for 1km range\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 8,Page No:464"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# variable Declaration\nPW      = 10*10**-6;         # pulse width in sec\nf       = 10*10**9;          # frequency in Hz\nfm      = 1000;              # modulating frequency\n\n# calculations\nBW_M    = 1/float(PW);              # matched bandwidth\ncf1     = f+fm;             # closest freq.\ncf2     = f-fm;             # closest freq.\nfo      = f;                # centre freq.\n\n# Output\nprint'Centre of frequency spectrum = %d Khz'%(fo/float(10**3));\nprint'The two closet frequencies to the center of the spectrum are %d Khz'%(cf1/float(10**3)),' and %d Khz'%(cf2/float(10**3));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Centre of frequency spectrum = 10000000 Khz\nThe two closet frequencies to the center of the spectrum are 10000001 Khz  and 9999999 Khz\n"
+      }
+     ],
+     "prompt_number": 7
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 9,Page No:464"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nfc1     = 495;      # freq in Mhz\nfc2     = 505;      # freq in Mhz\n\n# Calculations\nfo      = (fc1 + fc2)/float(2);        # Center of spectrum in Mhz\nBW      = fc2 - fc1;            # Bandwidth in Mhz\nPW      = 1/float(BW);                 # compressed pulse width in us\n\n# Result\nprint'Center of spectrum = %d Mhz\\n'%fo,'Matched Bandwidth = %d Mhz\\n'%BW,'Compressed Pulse width = %3.1fus'%PW;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Center of spectrum = 500 Mhz\nMatched Bandwidth = 10 Mhz\nCompressed Pulse width = 0.1us\n"
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 10,Page No:464"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# variable Declaration\nf       = 10**9;         # CW radar waveform freq.\nfm      = 100;           # modulation freq. in Hz\nMaxfD   = 500;           # max freq deviation in Hz\nc       = 3*10**8;       # vel. of EM waves in m/s\n\n# Calculations\nMf      = MaxfD/float(fm);      # Modulation index\nBW      = 2*(Mf + 1)*fm # Bandwidth\nRR      = c/float((2*BW));     # Range Resolution in m\n\n# Result\nprint'Bandwidth = %d Hz\\n'%BW,'Range Resolution = %d Km'%(RR/float(1000));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Bandwidth = 1200 Hz\nRange Resolution = 125 Km\n"
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 11,Page No:465"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nf       = 10**9;         # Centre freq. of spectrum\nt       = 13             # pulse width in us\nN       = 13;            # N-bit Barker code\n\n# Calculations\nSub_PW  = t/float(N);          # sub pulsewidth\nmatch_BW= 1/float(Sub_PW);     # Matched bandwidth in Mhz\n\n# Output\nprint'Matched Bandwidth = %d Mhz\\n'%match_BW,'Center Frequency of the spectrum = %d Ghz'%(f/float(10**9));\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Matched Bandwidth = 1 Mhz\nCenter Frequency of the spectrum = 1 Ghz\n"
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 12,Page No:479"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPW      = 10**-6;            # Pulse width in sec\nPp      = 100*10**3;          # Peak power in watts\nPRF     = 1000;              # pulse rep.rate\nN_target= 20;                # no of target hits in 1 dwell period\n\n# Calculations\nPE      = Pp*PW;            # Pulse energy in Joule\nLE      = N_target *PE;     # look energy\nDC      = PW*PRF            # Duty cycle\nPav     = Pp*DC;            # Average power\nPavg    = 10*math.log10(Pav);    # Avg power in dB\n\n# result\nprint'Average power = %d dB\\n'%Pavg,'Look Energy = %3.0f Joules'%LE;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Average power = 20 dB\nLook Energy =   2 Joules\n"
+      }
+     ],
+     "prompt_number": 11
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 13,Page No:479"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPW      = 10**-6;            # Pulse width in sec\nPp      = 100*10**3;         # Peak power in watts\nPRF     = 1000;              # pulse rep.rate\nN_target= 20;                # no of target hits in 1 dwell period\n\n# Calculations\nPE      = Pp*PW;            # Pulse energy in Joule\nLE      = N_target *PE;     # look energy\nDC      = PW*PRF            # Duty cycle\nPav     = Pp*DC;            # Average power\nPavg    = 10*math.log10(Pav);    # Avg power in dB\nPp_dB   = 10*math.log10(Pp);     # Peak power in dB\nDCCF    = Pp_dB - Pavg      # Duty cycle correction factor\n\n# result\nprint'Duty cycle correction factor = %d dB'%DCCF;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Duty cycle correction factor = 30 dB\n"
+      }
+     ],
+     "prompt_number": 20
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 14,Page No:479"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nG_rx        = 97;       # Rx gain in dB\nBn          = 5*10**6;   # Bandwidth in Hz\nTo          = 300;      # temperature in kelvin\nK           = 1.38*10**-23;  # Boltzmann constant in J/k\nn           = -3             # o/p noise power in dBm\n\n# calculations\nPn_dB      = n-G_rx       # input noise power\nPn         = 10**(Pn_dB/float(10))*10**-3       # converting from dBm to watts\n# Pn      = KToBnF;\nF          = Pn/float((K*To*Bn))  # Noise Factor\nT          = To*(F - 1);    # Equivalent Noise Temperature\n\n# Result\nprint'Equivalent Noise Temperature = %3.2d \u00b0K'%T;\n\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Equivalent Noise Temperature = 1149 \u00b0K\n"
+      }
+     ],
+     "prompt_number": 29
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 15,Page No:480"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nGx      = 60;       # gain of Rx 'X' in dB\nGy      = 70;       # gain of Rx 'Y' in dB\nFx      = 3;        # Noise factor of 'X'\nFy      = 2;        # Noise factor of 'Y'\n\n# calculations\nGx_W    = 10**(Gx/float(10));    # gain in watts\nGy_W    = 10**(Gy/float(10));    # gain in watts\n# k    = Pnx/float(Pny);      # Ratio of noise power levels produced at the o/p's of Rx 'X' and 'Y'\nk       = (Fx*Gx_W)/float((Fy*Gy_W));    # Ratio of noise power levels produced at the o/p's of Rx 'X' and 'Y'\n\n# result\nprint'Ratio of noise power levels produced at the outputs of Rx X and Y = %3.2f'%k;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Ratio of noise power levels produced at the outputs of Rx X and Y = 0.15\n"
+      }
+     ],
+     "prompt_number": 30
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 16,Page No:480"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n\n# Variable Declaration\nPn      = -70;          # Noise power in dBm\nfl      = 10**6;         # lower cut-off freq in Hz\nfh      = 11*(10**6);      # upper cut-off freq in Hz\nBP_fl   = 13*(10**6);      # Bandpass filter lower cutoff freq\nBP_fh   = 14*(10**6);      # Bandpass filter lower cutoff freq\n\n# Calculations\nPn_W    = (10**(Pn/10))*10**-3;     # coversion from dBm to Watts\nBW      = fh - fl\nPSD     = Pn_W/BW              # Noise power spectral density\n# Since white noise has the same spectral power density through the frequency spectrum,\n# therefore Noise power in second case\nB       = BP_fh - BP_fl\nPn_2    = PSD*B;                # Noise power in second case\n\n# Output\nprint'Noise power for BandPass filter having Cutoff frequencies 13Mhz and 14Mhz = %3.0e W'%Pn_2;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Noise power for BandPass filter having Cutoff frequencies 13Mhz and 14Mhz = 1e-11 W\n"
+      }
+     ],
+     "prompt_number": 12
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": "Example 17,Page No:483"
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": "import math\n# Given Data from Figure triagle OAB\nOA      = 100       # in Km\nOB      = OA*math.cos(60*math.pi/180);       # Range of Target 2\n\n# Result\nprint'Range of Target-2 = %d Km\\n Azimuth angle of target-1 = 60\u00b0\\n Azimuth angle of Target-2 = 120\u00b0'%OB;\n\n",
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": "Range of Target-2 = 50 Km\n Azimuth angle of target-1 = 60\u00b0\n Azimuth angle of Target-2 = 120\u00b0\n"
+      }
+     ],
+     "prompt_number": 13
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main1.png b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main1.png
new file mode 100644
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diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main2.png b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main2.png
new file mode 100644
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+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main2.png
diff --git a/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main3.png b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main3.png
new file mode 100644
index 00000000..a681c436
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+++ b/Microwaves_and_Radar_Principles_and_Applications_by_A._K._Maini/screenshots/main3.png
diff --git a/sample_notebooks/AumkarRane/Chapter9.ipynb b/sample_notebooks/AumkarRane/Chapter9.ipynb
new file mode 100644
index 00000000..49a8b300
--- /dev/null
+++ b/sample_notebooks/AumkarRane/Chapter9.ipynb
@@ -0,0 +1,194 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 9 : Special Theory of Relativity"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 1 , Page number 284"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Change in length in diameter= 6.37 *10**-2 m\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "l=2*6371        #Diameter of earth\n",
+    "v=30            #velocity\n",
+    "c=3*10**5       #velocity of light\n",
+    "\n",
+    "#Calculations\n",
+    "dell=(l*v**2)/(2*c**2)/10**-5\n",
+    "\n",
+    "#Result\n",
+    "print\"Change in length in diameter=\",round(dell,2),\"*10**-2 m\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 2 , Page number 284"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 27,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The minimum speed v=  0.99999996247 c\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "delt=10               #time duration at earth\n",
+    "delt1=1/365 \n",
+    "\n",
+    "#Calculations\n",
+    "v=math.sqrt(1-(delt1/delt)**2)\n",
+    "\n",
+    "#Result\n",
+    "print\"The minimum speed v= \",v,\"c\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 3 , Page number 285"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 39,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "(1) The time taken on earth (t) =  21.05 year\n",
+      "(2) The time taken on spaceship  (t1) =  6.53 year\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "L0=20           #The distance of the star\n",
+    "v=0.95          #velocity\n",
+    "\n",
+    "#Calculations\n",
+    "t=L0/v\n",
+    "L=L0*math.sqrt(1-v**2)\n",
+    "L=round(L,1)\n",
+    "t1=(L*3*10**8)/(v*3*10**8)\n",
+    "\n",
+    "#Result\n",
+    "print\"(1) The time taken on earth (t) = \",round(t,2),\"year\"\n",
+    "print\"(2) The time taken on spaceship  (t1) = \",round(t1,2),\"year\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 4 , Page number 285"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 45,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "(1) The height will be same and the length(L0)  =  6.25 m\n",
+      "(2) The time elapsed on his friend's watch(t1) =  8.0 sec\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "L=5 #Lenth\n",
+    "v=0.6 #velocity\n",
+    "t=10 #time\n",
+    "\n",
+    "#Calculations\n",
+    "L0=L/math.sqrt(1-v**2)\n",
+    "t1=t*math.sqrt(1-v**2)\n",
+    "\n",
+    "#Result\n",
+    "print\"(1) The height will be same and the length(L0)  = \",L0,\"m\"\n",
+    "print\"(2) The time elapsed on his friend's watch(t1) = \",t1,\"sec\""
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/sample_notebooks/DevikaRaj/Chapter6.ipynb b/sample_notebooks/DevikaRaj/Chapter6.ipynb
new file mode 100644
index 00000000..d7462a9e
--- /dev/null
+++ b/sample_notebooks/DevikaRaj/Chapter6.ipynb
@@ -0,0 +1,483 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 6: Measuring instruments"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 1: pg 235"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The shunt resistance required in (ohm) =  0.163\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 235\n",
+    "#calculate the shunt resistance\n",
+    "# Given data\n",
+    "Rm = 8.;# in ohm\n",
+    "Im = 20.;# in mA\n",
+    "Im = Im * 10**-3;# in A\n",
+    "I = 1.;# in A\n",
+    "#calculations\n",
+    "# Multiplying factor\n",
+    "N = I/Im;\n",
+    "# Shunt resistance\n",
+    "Rsh = Rm/(N-1);# in ohm\n",
+    "#results\n",
+    "print \"The shunt resistance required in (ohm) = \",round(Rsh,3)\n",
+    " "
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2: pg 235"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The multiplying factor is 241.0\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 235\n",
+    "#calculate the multiplying factor\n",
+    "# Given data\n",
+    "Rm = 6;# in ohm\n",
+    "Rsh = 0.025;# in ohm\n",
+    "#calculations\n",
+    "N = 1 + (Rm/Rsh);# multiplying factor\n",
+    "#results\n",
+    "print \"The multiplying factor is\",N\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 3: pg 235"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The resistance to be connected in parallel in (ohm) =  0.0761\n",
+      "The resistance to be connected in series in (ohm) =  661.67\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 235\n",
+    "#calculate the resistances to be connected in parallel and series\n",
+    "# Given data\n",
+    "Rm = 5.;# in ohm\n",
+    "Im = 15.;# in mA\n",
+    "Im = Im * 10**-3;# in A\n",
+    "I = 1.;# in A\n",
+    "#calculations\n",
+    "N = I/Im;# multiplying factor\n",
+    "Rsh = Rm/(N-1);# in ohm\n",
+    "print \"The resistance to be connected in parallel in (ohm) = \",round(Rsh,4)\n",
+    "V = 10;# in V\n",
+    "Rs = (V/Im)-Rm;# in ohm\n",
+    "print \"The resistance to be connected in series in (ohm) = \",round(Rs,2)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 4: pg 236"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The current range of instrument in A is 50.0\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 236\n",
+    "#calculate the current range of the instrument\n",
+    "# Given data\n",
+    "V=250.;# full scale voltage reading in V\n",
+    "Rm = 2.;# in ohm\n",
+    "Rsh = 2.;# in m ohm\n",
+    "Rsh = Rsh * 10**-3;# in ohm\n",
+    "R = 5000.;# in ohm\n",
+    "#calculations\n",
+    "Im = V/(Rm+R);# in A\n",
+    "Ish = (Im*Rm)/Rsh;# in A\n",
+    "# Current range of instrument\n",
+    "I = Im+Ish;# in A\n",
+    "#results\n",
+    "print \"The current range of instrument in A is\",round(I)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 5: pg 236"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The percentage error in (percentage) is 249.38\n",
+      "The answer is a bit different from textbook due to rounding off error\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 236\n",
+    "#calculate the percentage error\n",
+    "import math\n",
+    "from math import acos,pi,cos\n",
+    "# Given data\n",
+    "V = 230.;# in V\n",
+    "I = 35.;# in A\n",
+    "N = 200.;\n",
+    "t = 64.;# in sec\n",
+    "kwh = 500.;\n",
+    "#calculations\n",
+    "phi= acos(0.8);# in radians\n",
+    "Er = N/kwh;# in kWh\n",
+    "Et =  V*I*cos(phi)*t;# in Joules\n",
+    "Et = Et/3600.;# in W hour\n",
+    "Et = Et * 10**-3;# in kWh\n",
+    "# percentage error\n",
+    "PerError = ((Er-Et)/Et)*100;# in %\n",
+    "#results\n",
+    "print \"The percentage error in (percentage) is\",round(PerError,2)\n",
+    "print 'The answer is a bit different from textbook due to rounding off error'\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 6: pg 237"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The percentage error in (percentage) is  3.22\n",
+      "The answer is a bit different from textbook due to rounding off error\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 237\n",
+    "#calculate the percentage error\n",
+    "from math import acos,cos,pi\n",
+    "# Given data\n",
+    "I = 50.;# in A\n",
+    "V = 230.;# in V\n",
+    "N = 61.;\n",
+    "t = 37.;# in sec\n",
+    "KWh = 500.;\n",
+    "#calculations\n",
+    "phi= acos(1);# in radians\n",
+    "Er = N/KWh;# in kWh\n",
+    "Et = V*I*cos(phi)*t;# in Joules\n",
+    "Et = Et/3600.;# in Wh\n",
+    "Et = Et*10**-3;# in kWh\n",
+    "# Percentage error\n",
+    "PerError = ((Er-Et)/Et)*100;# in %\n",
+    "#results\n",
+    "print \"The percentage error in (percentage) is \",round(PerError,2)\n",
+    "print 'The answer is a bit different from textbook due to rounding off error'"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 7: pg 237"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The series resistance in ohm is 24997.5\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 237\n",
+    "#calculate the series resistance\n",
+    "# Given data\n",
+    "Im = 20.;# in mA\n",
+    "Im =  Im * 10**-3;# in A\n",
+    "Vm = 50.;# in mV\n",
+    "Vm = Vm * 10**-3;# in V\n",
+    "V = 500.;# in V\n",
+    "#calculations\n",
+    "Rm = Vm/Im;# in ohm\n",
+    "Rs = (V/Im)-Rm;# in ohm\n",
+    "#results\n",
+    "print \"The series resistance in ohm is\",Rs\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 8: pg 238"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The value of Rs in (ohm) is 9950.0\n",
+      "The value of Rsh in (ohm) is 0.505\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 238\n",
+    "#calculate the values of resistances\n",
+    "# Given data\n",
+    "Rm = 50;# in ohm\n",
+    "Im = 10;# in mA\n",
+    "Im = Im * 10**-3;# in A\n",
+    "V = 100;# in V\n",
+    "#calculations\n",
+    "Rs = (V/Im)-Rm;# in ohm\n",
+    "print \"The value of Rs in (ohm) is\",Rs\n",
+    "N = 1/Im;\n",
+    "Rsh = Rm/(N-1);# in ohm\n",
+    "print \"The value of Rsh in (ohm) is\",round(Rsh,3)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 9: pg 238"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The percentage error in (percentage) is 2.08\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 238\n",
+    "#calculate the percentage error\n",
+    "# Given data\n",
+    "from math import acos,cos\n",
+    "I = 40.;# in A\n",
+    "V = 230.;# in V\n",
+    "N = 600.;\n",
+    "t = 46.;# in sec\n",
+    "#calculations\n",
+    "phi= acos(1);# in radians\n",
+    "P = V*I*cos(phi);# in W\n",
+    "P = P * 10**-3;# in kW\n",
+    "# 1 kWh = 500 revolution \n",
+    "P = P * 500.;# in revolution\n",
+    "T = (3600./t)*60;# in revolution\n",
+    "# Percentage error\n",
+    "PerError = ((T-P)/P)*100;# in %\n",
+    "#results\n",
+    "print \"The percentage error in (percentage) is\",round(PerError,2)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 10: pg 238"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The percentage error in (percentage) is 4.167\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 238\n",
+    "#calculate the percentage error\n",
+    "# Given data\n",
+    "N = 100.;\n",
+    "I = 20.;# in A\n",
+    "V = 210.;# in V\n",
+    "pf = 0.8;# in lad\n",
+    "Er = 350.;# in rev\n",
+    "a = 3.36;# assumed\n",
+    "#calculations\n",
+    "Et = (a*3600.)/3600;# in kWh\n",
+    "# 1 kWh = 100;#  revolution\n",
+    "Et = Et*N;# revolution\n",
+    "# Percentage error\n",
+    "PerError = ((Er-Et)/Et)*100;# in %\n",
+    "#results\n",
+    "print \"The percentage error in (percentage) is\",round(PerError,3)\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 11: pg 239"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The percentage error in (percentage) is 3.22\n"
+     ]
+    }
+   ],
+   "source": [
+    "#pg 239\n",
+    "#calculate the percentage error\n",
+    "# Given data\n",
+    "I = 5.;# in A\n",
+    "V = 230.;# in V\n",
+    "N = 61.;# number of revolution\n",
+    "t = 37.;# in sec\n",
+    "# speed of the disc\n",
+    "discSpeed= 500.;# in rev/kWh\n",
+    "#calculations\n",
+    "Er = N/discSpeed;\n",
+    "Et = (V*I*t)/(3600*100);\n",
+    "# percentage error\n",
+    "PerError = ((Er-Et)/Et)*100;# in %\n",
+    "#results\n",
+    "print \"The percentage error in (percentage) is\",round(PerError,2)\n"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}