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diff --git a/Microwave_and_Radar_Engineering/Chapter_4.ipynb b/Microwave_and_Radar_Engineering/Chapter_4.ipynb new file mode 100644 index 00000000..c8b2fe93 --- /dev/null +++ b/Microwave_and_Radar_Engineering/Chapter_4.ipynb @@ -0,0 +1,1238 @@ +{ + "metadata": { + "name": "" + }, + "nbformat": 3, + "nbformat_minor": 0, + "worksheets": [ + { + "cells": [ + { + "cell_type": "heading", + "level": 1, + "metadata": {}, + "source": [ + "Chapter 4:Microwave Transmission Lines" + ] + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.1, Page number 141" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "''' Calculate - \n", + "a)Inductance per unit length\n", + "b)Capacitance per unit lengh\n", + "c)Characteristic impedance\n", + "d)velocity of propagation'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "d = 0.49 #diameter of inner conductor(cm)\n", + "D = 1.10 #diameter of outer conductor(cm)\n", + "e = 2.3 #polyethylene dielectric\n", + "c = 3*10**8 #velocity of light(m/s)\n", + "\n", + "#Calculations\n", + "L = 2*10**-7*math.log(D/d)\n", + "C = (55.56*10**-12*e)/(math.log(D/d))\n", + "Ro = (60*math.log(D/d))/(math.sqrt(e))\n", + "v = c/(math.sqrt(e))\n", + "\n", + "#Results\n", + "print \"Inductance per unit length is\",round(L,8),\"H/m\"\n", + "print \"Capacitance per unit length is\",round(C,12),\"PF/m\"\n", + "print \"Characteristic impedance is\",round(Ro,3),\"Ohms\"\n", + "print \"Velocity of propagation is\",round(v,3),\"m/s\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Inductance per unit length is 1.6e-07 H/m\n", + "Capacitance per unit length is 1.58e-10 PF/m\n", + "Characteristic impedance is 31.993 Ohms\n", + "Velocity of propagation is 197814142.019 m/s\n" + ] + } + ], + "prompt_number": 48 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.2, Page number 142" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate aatenuation constant, phase constant, phase velocity, relative permittivity and power loss'''\n", + "\n", + "import math\n", + "\n", + "#Variable declartion\n", + "R = 0.05 #Ohms/m\n", + "L = 1.6*10**-7 #Inductance(from example 4.1)\n", + "C = 1.58*10**-10 #Capacitance(from example 4.1)\n", + "w = 2*math.pi\n", + "c = 3*10**8 #velocity of light(m/s)\n", + "e = 2.3 #polyethylene dielectric(from example 4.1)\n", + "Pin = 480 #Input power(W)\n", + "l = 50 #line length(m)\n", + "\n", + "#Calculations\n", + "zo=math.sqrt(L/C)\n", + "alpha = R/(2*zo)\n", + "B = w*math.sqrt(L*C)\n", + "Vp = 1/math.sqrt(L*C)\n", + "e = (C/Vp)**2\n", + "Pl = Pin*2*l\n", + "\n", + "#Results\n", + "print \"Attenuation constant =\",round(alpha,5),\"Np/m\"\n", + "print \"Phase constant =\",round(B,8),\"rad/m\"\n", + "print \"Phase velocity =\",round(Vp*10**-6,2),\"*10**-6 m/s\"\n", + "print \"Relative permittivity =\",e\n", + "print \"Power loss =\",round(Pl),\"W\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Attenuation constant = 0.00079 Np/m\n", + "Phase constant = 3e-08 rad/m\n", + "Phase velocity = 198.89 *10**-6 m/s\n", + "Relative permittivity = 6.3108992e-37\n", + "Power loss = 48000.0 W\n" + ] + } + ], + "prompt_number": 67 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.3, Page number 142" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate breakdown power'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "f = 9.375*10**10 #Frequency(Hz)\n", + "c = 3*10**8 #velocity of light(m/s)\n", + "b_a = 2.3\n", + "\n", + "#Calculations\n", + "lamda = c/f\n", + "#Since b_by_a = 2.3 and b+a <lamda/pi, therefore\n", + "a = 2.42 #(cm)\n", + "P = 3600*a**2*math.log(b_a)\n", + "\n", + "#Results\n", + "print \"The brakdown power of the airfilled coaxial cable is\", round(P),\"W\"\n", + "print \"Please note the answer given in the textbook is wrong\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The brakdown power of the airfilled coaxial cable is 17560.0 W\n", + "Please note the answer given in the textbook is wrong\n" + ] + } + ], + "prompt_number": 4 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.4, Page number 142" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Determine the characteristic impedance and velocity of propagation'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "b = 0.3175 #distance between the ground planes(cm)\n", + "d = 0.0539 #diameter of circular conductor(cm)\n", + "e = 2.32 #dielectric constant\n", + "c = 3*10**8 #velocity of light(m/s)\n", + "\n", + "#Calculations\n", + "zo = (60*math.log((4*b)/(math.pi*d)))/math.sqrt(e)\n", + "v = c/math.sqrt(e)\n", + "\n", + "#Results\n", + "print \"Charactritic impedance =\",round(zo,2),\"Ohms\"\n", + "print \"Velocity of propagation =\",round(v,2),\"m/s\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Charactritic impedance = 79.37 Ohms\n", + "Velocity of propagation = 196959649.29 m/s\n" + ] + } + ], + "prompt_number": 15 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.5, Page number 143" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "''' Determine -\n", + "a)Characteristic impedance\n", + "b)Dielectric constant\n", + "c)Velocity of propagation'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "e = 9.7 #Dielectric constant\n", + "W_h = 0.5 #for case a\n", + "W_b = 5. #for case b\n", + "c = 3*10**8 #speed of light(m/s)\n", + "\n", + "#Calculations\n", + "#Case a\n", + "x = (1/math.sqrt(1+12+((1/W_h)**2))+0.04*((1-W_h)**2))\n", + "Eeff1 = ((e+1)/2)+(((e-1)/2)*x)\n", + "Zo1 = 60/math.sqrt(Eeff1)*math.log((8*(1/W_h)+W_h/4))\n", + "v1 = c/math.sqrt(Eeff1)\n", + "\n", + "#Case b\n", + "y = 1/(math.sqrt(1+12*(1/W_b)))\n", + "Eeff2 = ((e+1)/2)+(((e-1)/2)*y)\n", + "z = 1/(W_b+1.393+0.667*math.log(1.444+W_b))\n", + "Zo2 = (120*math.pi*z)/math.sqrt(Eeff2)\n", + "v2 = c/math.sqrt(Eeff2)\n", + "\n", + "#Results\n", + "print \"Case a\"\n", + "print \"Characteristic impedance =\",round(Zo1,2),\"Ohms\"\n", + "print \"Effective dielectric constant =\",round(Eeff1,2)\n", + "print \"Velocity of propagation =\",round(v1,2),\"m/s\\n\"\n", + "\n", + "\n", + "print \"Case b\"\n", + "print \"Characteristic impedance =\",round(Zo2,2),\"Ohms\"\n", + "print \"Effective dielectric constant =\",round(Eeff2,2)\n", + "print \"Velocity of propagation =\",round(v2,2),\"m/s\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Case a\n", + "Characteristic impedance = 65.69 Ohms\n", + "Effective dielectric constant = 6.45\n", + "Velocity of propagation = 118138347.97 m/s\n", + "\n", + "Case b\n", + "Characteristic impedance = 17.78 Ohms\n", + "Effective dielectric constant = 7.71\n", + "Velocity of propagation = 108048536.19 m/s\n" + ] + } + ], + "prompt_number": 54 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.6, Page number 144" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "''' Calculate ratio of circular waveguide cross-sectional area to the rectangular waveguide cross section when - \n", + "a) TE wave is propagated\n", + "b) TM wave is propagated'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "a1 = 1.70645 #for case a\n", + "b1 = a1/2 #for case a\n", + "b2 = 1.4621 #for case b\n", + "\n", + "#Calculations\n", + "#Case a(For TE10 mode)\n", + "Area_rw1 = a1*b1\n", + "Area_cw1 = math.pi\n", + "Ratio1 = Area_cw1/Area_rw1\n", + "\n", + "#Case b(For TM mode)\n", + "Area_rw2 = b2**2\n", + "Area_cw2 = math.pi\n", + "Ratio2 = Area_cw2/Area_rw2\n", + "\n", + "\n", + "#Results\n", + "print \"Case a\"\n", + "print \"Ratio of area of circular to area of rectangular waveguide =\",round(Ratio1,1),\"\\n\"\n", + "print \"Case b\"\n", + "print \"Ratio of area of circular to area of rectangular waveguide =\",round(Ratio2,1)" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Case a\n", + "Ratio of area of circular to area of rectangular waveguide = 2.2 \n", + "\n", + "Case b\n", + "Ratio of area of circular to area of rectangular waveguide = 1.5\n" + ] + } + ], + "prompt_number": 53 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.7, Page number 146" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate breadth of rectangular waveguide for dominant mode TE10'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "f = 9.*10**9 #frequency(Hz)\n", + "lamda_g = 4. #guide wavelength(cm)\n", + "c = 3.*10**10 #velocity of propagation(cm/s)\n", + "\n", + "#Calculations\n", + "lamda_o = c/f\n", + "lamda_c = math.sqrt((lamda_o**2)/(1-(lamda_o**2/lamda_g**2)))\n", + "#For TE10 mode,\n", + "a = lamda_c/2\n", + "b = lamda_c/4 #@since a=2b\n", + "#Results\n", + "print \"The breadth of rectangular waveguide is\",round(b,2),\"cms\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The breadth of rectangular waveguide is 1.51 cms\n" + ] + } + ], + "prompt_number": 9 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.8, Page number 147" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "''' Determine the cut-off wavelength, guide wavelength, group and phase velocities'''\n", + "\n", + "#Variable declaration\n", + "a = 10 #breadth of waveguide(cms)\n", + "f = 2.5*10**9 #frequency of signal(Hz)\n", + "c = 3*10**10 #velocity of propagation(cm/s)\n", + "\n", + "#Calculations\n", + "lamda_c = 2*a #cut-off wavelength\n", + "lamda_o = c/f \n", + "x = math.sqrt(1-((lamda_o/lamda_c)**2))\n", + "lamda_g = (lamda_o/x) #guided wavelength\n", + "Vp = c/x #Phase velocity\n", + "Vg = c**2/Vp #Group velocity\n", + "\n", + "#Results\n", + "print \"The cut-off wavelength is\", round(lamda_c,2),\"cm\"\n", + "print \"The guided wavelength is\",round(lamda_g,3),\"cm\"\n", + "print \"The pahse velocity is\",round((Vp/1E+10),2),\"*10^10 cm/sec\"\n", + "print \"The group velocity is\",round((Vg/1E+10),2),\"*10^10 cm/sec\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The cut-off wavelength is 20.0 cm\n", + "The guided wavelength is 15.0 cm\n", + "The pahse velocity is 3.75 *10^10 cm/sec\n", + "The group velocity is 2.4 *10^10 cm/sec\n" + ] + } + ], + "prompt_number": 26 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.9, Page number 147" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "''' Find the following - \n", + "a)possible modes\n", + "b)cut-off frequencies\n", + "c)guide wavelength'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "a = 2.5 #length of guide(cms)\n", + "b = 1 #breadth of guide(cms)\n", + "f = 8.66 #cut-off frequency(Hz)\n", + "c = 3*10**10 #velocity of propagation(m/s)\n", + "\n", + "#Calculations\n", + "lamda_o = c/f\n", + "#condition for wave to propagate is lamda_c>lamda_o. Therefore for TE01 mode,\n", + "lamda_c1 = 2*b\n", + "if lamda_c1<lamda_o:\n", + " print \"TE01 does not propgate\"\n", + "lamda_c2 = 2*a #for TE10 mode\n", + "if lamda_c2>lamda_o:\n", + " print \"TE10 is a possible mode\"\n", + "fc = c/lamda_c2\n", + "lamda_c3 = (2*a*b)/math.sqrt((a**2)+(b**2)) #for TE11 and TM11 modes\n", + "if lamda_c3<lamda_o:\n", + " print \"Both TE11 and TM11 do not propagate as higher modes\"\n", + "lamda_g = lamda_o/math.sqrt(-1*(1-((lamda_o/lamda_c2)**2)))\n", + "\n", + "#Results\n", + "print \"Cut-off frequency =\",round((fc/1E+9),3),\"GHz\"\n", + "print \"Guide wavelength =\",round(lamda_g,3),\"cms\"\n", + "print \"From the analysis, we conclude that only TE10 mode is possible\\n\"\n", + "print \"Case ii\"\n", + "print \"Lamda_c for TM11 is equal to lamda_c for TE11 =\",round(lamda_c3,3),\"cms which means that TM11 also does not propagate\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "TE01 does not propgate\n", + "Both TE11 and TM11 do not propagate as higher modes\n", + "Cut-off frequency = 6.0 Hz\n", + "Guide wavelength = 5.0 cms\n", + "From the analysis, we conclude that only TE10 mode is possible\n", + "\n", + "Case ii\n", + "Lamda_c for TM11 is equal to lamda_c for TE11 = 1.857 cms which means that TM11 also does not propagate\n" + ] + } + ], + "prompt_number": 28 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.10, Page number 148" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Find - \n", + "a)the required size of cross setional area of the guide\n", + "b)the frequencies that can be used for this mode of propagation'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "lamda_c = 10 #cut-off wavelength(cms)\n", + "c = 3*10**10 #velocity of propagation\n", + "\n", + "#Calculations\n", + "#For TE11 mode in a circular waveguide,\n", + "r = (lamda_c*1.841)/(2*math.pi) #radius of circular waveguide(cms)\n", + "a = math.pi*r**2 #area of circular waveguide\n", + "fc = c/lamda_c #cut-off frequency(Hz)\n", + "\n", + "#Results\n", + "print \"The required cross sectional area is\", round(a,3),\"cms^2\"\n", + "print \"Frequencies above\",round((fc/1E+9),2),\"GHz can be propagated throught the waveguide\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The required cross sectional area is 26.971 cms^2\n", + "Frequencies above 3.0 GHz can be propagated throught the waveguide\n" + ] + } + ], + "prompt_number": 1 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.11, Page number 149" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Finding all the modes of propagation'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "f = 5*10**9 #frequecy(Hz)\n", + "a = 4 #length of guide(cms)\n", + "b = 3 #breadth of guide(cms)\n", + "c = 3*10**10 #velocity of propagation(m/s)\n", + "\n", + "#Calculations & Results\n", + "lamda_o = c/f\n", + "#For TE waves:\n", + "#For TE01 mode - m = 0, n = 1\n", + "lamda_c1 = 2*b\n", + "if lamda_c1<=lamda_o:\n", + " print \"TE01 does not propgate\"\n", + "\n", + "#For TE10 mode - m=1, n=0\n", + "lamda_c2 = 2*a\n", + "if lamda_c3<lamda_o:\n", + " print \"TE10 is a possible mode\"\n", + " \n", + "#For TE11 mode - m=1, n=1\n", + "lamda_c3 = (2*a*b)/math.sqrt((a**2)+(b**2))\n", + "if lamda_c3<lamda_o:\n", + " print \"TE11 does not propgate\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "TE01 does not propgate\n", + "TE10 is a possible mode\n", + "TE11 does not propgate\n" + ] + } + ], + "prompt_number": 8 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.12, Page number 149" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "''' Find - \n", + "a)cut-off wavelength\n", + "b)cut-off frequency\n", + "c)wavelength in the guide'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "d = 4 #inner diameter of circular waveguide(cms)\n", + "c = 3*10**10 #velocity od propagation(m/s)\n", + "fs = 5*10**9 #signal frequency(Hz)\n", + "\n", + "#Calculations\n", + "r = d/2 #radius(cms)\n", + "lamda_c = (2*math.pi*r)/1.841\n", + "fc = c/lamda_c\n", + "lamda_o = c/fs\n", + "lamda_g = lamda_o/math.sqrt(1-((lamda_o/lamda_c)**2))\n", + "\n", + "#Results\n", + "print \"Cut-off wavelength =\",round(lamda_c,3),\"cms\"\n", + "print \"Cut-off frequency =\",round((fc/1E+9),3),\"GHz\"\n", + "print \"Guide wavelength =\",round(lamda_g,3),\"cms\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Cut-off wavelength = 6.826 cms\n", + "Cut-off frequency = 4.395 GHz\n", + "Guide wavelength = 12.584 cms\n" + ] + } + ], + "prompt_number": 35 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.13, Page number 150" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Find the frequency of wave'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "a = 6. #length of rectangular waveguide(cms)\n", + "b = 4. #breadth of rectangular waveguide(cms)\n", + "d = 4.55 #distance between maximum and minimum(cms)\n", + "c = 3.*10**10 #velocity of propagation(cm/s)\n", + "\n", + "#Calculations\n", + "#For TE10 mode:\n", + "lamda_c = 2*a\n", + "lamda_g = d*4\n", + "lamda_o = math.sqrt(1./(((1./lamda_g**2)+(1./lamda_c**2))))\n", + "f = c/lamda_o\n", + "\n", + "#Results\n", + "print \"Frequency of wave is\",round((f/1E+9),2),\"GHz\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Frequency of wave is 2.99 GHz\n" + ] + } + ], + "prompt_number": 53 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.14, Page number 151" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Determine guide wavelength, phase constant and phase velocity'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "b = 2.5 #breadth of rectangular waveguide(cms)\n", + "a = 5. #length of rectangular waveguide(cms)\n", + "c = 3*10**10 #velocity of propagation(cm/s)\n", + "lamda_o = 4.5 #wavelength(cms)\n", + "\n", + "#Calculations\n", + "#For TE10 mode which is the dominant mode:\n", + "lamda_c = 2*a\n", + "lamda_g = lamda_o/math.sqrt(1-((lamda_o/lamda_c)**2))\n", + "Vp = c/math.sqrt(1-((lamda_o/lamda_c)**2))\n", + "B = (2*math.pi*math.sqrt((lamda_c**2)-(lamda_o**2)))/(lamda_o*lamda_c)\n", + "\n", + "#Results\n", + "print \"Solutions obtained in the textbook are incorrect due to calculation mistake in lamda_g\"\n", + "print \"Guide wavelength =\",round(lamda_g,3),\"cms\"\n", + "print \"Phase constant =\",round(B,3)\n", + "print \"Phase velocity =\",round(Vp,3),\"m/sec\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Solutions obtained in the textbook are incorrect due to calculation mistake in lamda_g\n", + "Guide wavelength = 5.039 cms\n", + "Phase constant = 1.247\n", + "Phase velocity = 33593550657.4 m/sec\n" + ] + } + ], + "prompt_number": 55 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.15, Page number 152" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''What modes are propagated at free space wavelength of(i)10cm (ii)5cm'''\n", + "\n", + "#Variable declaration\n", + "lamda_o1 = 10 #cms\n", + "lamda_o2 = 5 #cms\n", + "#lamda_c for different modes\n", + "TE10 = 16 #cms\n", + "TM11 = 7.16 #cms\n", + "TM21 = 5.6 #cms\n", + "\n", + "#Calculations\n", + "#For any wave to be propagated, lamda_c>lamda_o\n", + "\n", + "#Part(i)\n", + "x = [TE10, TM11, TM21]\n", + "#largest=x[0]\n", + "for large in x:\n", + " if large > lamda_o1:\n", + " largest=large\n", + "print \"Part(i)\\nSince lamda_c =\",(largest),\"which is greater than lamda_o1, only TE10 mode propagates\"\n", + "\n", + "#Part(ii)\n", + "print \"\\nPart(ii)\"\n", + "if TE10>lamda_o2:\n", + " print \"TE10 mode propagates\"\n", + " if TM11>lamda_o2:\n", + " print \"TM11 mode propagates\"\n", + " if TM21>lamda_o2:\n", + " print \"TM21 mode propagates\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Part(i)\n", + "Since lamda_c = 16 which is greater than lamda_o1, only TE10 mode propagates\n", + "\n", + "Part(ii)\n", + "TE10 mode propagates\n", + "TM11 mode propagates\n", + "TM21 mode propagates\n" + ] + } + ], + "prompt_number": 35 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.16, Page number 152" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Determine characteristic wave impedance'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "a = 3 #length of rectangular waveguide(cms)\n", + "b = 2 #breadth of rectangular waveguide(cms)\n", + "f = 10.*10**9 #frequency(Hz)\n", + "c = 3.*10**10 #velocity of propagation(cm/s)\n", + "n = 120*math.pi #intrinsic impedance\n", + "\n", + "#Calculations\n", + "lamda_c = (2*a*b)/(math.sqrt(a**2+b**2))\n", + "lamda_o = c/f\n", + "Ztm = n*math.sqrt(1-((lamda_o/lamda_c)**2))\n", + "\n", + "#Result\n", + "print \"Solution obtained in the textbook are incorrect due to calculation mistake in Ztm\"\n", + "print \"characteristic wave impedance =\",round(Ztm,3),\"Ohms\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Solution obtained in the textbook are incorrect due to calculation mistake in Ztm\n", + "characteristic wave impedance = 163.242 Ohms\n" + ] + } + ], + "prompt_number": 71 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.17, Page number 152" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Determine diameter of waveguide and guide wavelength'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "f = 6.*10**9 #frequency(Hz)\n", + "c = 3.*10**10 #velocity of propagation(cm/s)\n", + "\n", + "#Calculations\n", + "fc = 0.8*f\n", + "lamda_c = c/fc\n", + "D = (lamda_c*1.841)/math.pi\n", + "lamda_o = c/f\n", + "lamda_g = lamda_o/(math.sqrt(1-((lamda_o/lamda_c)**2)))\n", + "\n", + "#Results\n", + "print \"diameter of waveguide =\",round(D,4),\"cms\"\n", + "print \"guide wavelength =\",round(lamda_g,3),\"cms\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "diameter of waveguide = 3.6626 cms\n", + "guide wavelength = 8.333 cms\n" + ] + } + ], + "prompt_number": 65 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.18, Page number 153" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Analysis of TE01 mode'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "a = 1.5 #length of waveguide(cms)\n", + "b = 1 #breadth of waveguide(cms)\n", + "c = 3*10**10 #velocity of propagation\n", + "Er = 4 #dielectric\n", + "f = 6*10**9 #frequency(Hz)\n", + "\n", + "#Calculations and Results\n", + "lamda_c = 2*a\n", + "fc = c/lamda_c\n", + "if f<fc:\n", + " print \"The impressed frequency of 6GHz is less than the cut-off frequency and hence the signal will not pass through the guide\"\n", + "lamda1 = c/f\n", + "if lamda1>lamda_c:\n", + " print \"Since the wavelength of the impressed signal is longer than the cut-off wavelength, there is no propagation of wave\"\n", + "lamda2 = lamda1/math.sqrt(Er)\n", + "if lamda2<lamda1:\n", + " print \"The signal with 6GHz frequency will pass through the dielectric load waveguide\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The impressed frequency of 6GHz is less than the cut-off frequency and hence the signal will not pass through the guide\n", + "Since the wavelength of the impressed signal is longer than the cut-off wavelength, there is no propagation of wave\n", + "The signal with 6GHz frequency will pass through the dielectric load waveguide\n" + ] + } + ], + "prompt_number": 2 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.19, Page number 153" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate the amount of attenuation'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "a = 1.5*10**-2 #length of rectangular waveguide(m)\n", + "b = 1 #breadth of rectangular waveguide(cms)\n", + "f = 6*10**9 #frequency(Hz)\n", + "c = 3*10**10 #velocity of propagation(m/s)\n", + "m = 1\n", + "n = 0\n", + "mu = 4*math.pi*10**-7\n", + "e = 8.854*10**-12\n", + "\n", + "#Calculations\n", + "#For dominant TE10 mode,\n", + "lamda_c = 2*a\n", + "fc = c/lamda_c\n", + "w = 2*math.pi*f\n", + "alpha = math.sqrt((((m*math.pi)/a)**2)+(((n*math.pi)/b)**2)- ((w**2)*mu*e))\n", + "\n", + "#Results\n", + "print \"The amount of attenuation is\",round(alpha,2),\"nepass/m\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The amount of attenuation is 167.49 nepass/m\n" + ] + } + ], + "prompt_number": 21 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.20, Page number 154" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate the maximum power handling capacity of the waveguide'''\n", + "\n", + "#Variable declaration\n", + "a = 3\n", + "b = 1\n", + "f = 9.*10**9\n", + "Emax = 3.*10**3\n", + "c = 3.*10**10\n", + "\n", + "#Calculations\n", + "lamda_o = c/f\n", + "lamda_c = 2*a\n", + "lamda_g = lamda_o/(math.sqrt(1-((lamda_o/lamda_c)**2)))\n", + "P = 6.63*10**-4*Emax**2*a*b*(lamda_o/lamda_g)\n", + "\n", + "#Result\n", + "print \"Solution obtained in the textbook are incorrect due to calculation mistake in lamda_g\"\n", + "print \"The maximum power handling capacity of the waveguide =\",round((P/1E+3),3),\"kW\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Solution obtained in the textbook are incorrect due to calculation mistake in lamda_g\n", + "The maximum power handling capacity of the waveguide = 14.884 kW\n" + ] + } + ], + "prompt_number": 75 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.21, Page number 154" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate maximum power'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "f = 9*10**9 #frequency(Hz)\n", + "d = 5 #internal diameter(cms)\n", + "Emax = 300 #maximum field strength(V/cm)\n", + "c = 3*10**10 #velocity of propagation(m/s)\n", + "\n", + "#Calculations\n", + "lamda_o = c/f\n", + "#For domnant mode TE11,\n", + "lamda_c = (math.pi*d)/1.841\n", + "lamda_g = lamda_o/math.sqrt(1-((lamda_o/lamda_c)**2))\n", + "Pmax = 0.498*(Emax**2)*(d**2)*(lamda_o/lamda_g)\n", + "\n", + "#Results\n", + "print \"Maximum power =\",round((Pmax/1E+6),3),\"*10^6 W\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Maximum power = 1.049 *10^6 W\n" + ] + } + ], + "prompt_number": 76 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.22, Page number 155" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Find peak value of electric field occuring in the guide'''\n", + "\n", + "import math\n", + "\n", + "#Varaible declaration\n", + "c = 3.*10**10 #velocity of propagation(m/s)\n", + "f = 30.*10**9 #frequency(Hz)\n", + "a = 1 #length(cm)\n", + "b = 1 #breadth(cm)\n", + "n = 120*math.pi\n", + "\n", + "#Calclations\n", + "lamda_o = c/f\n", + "lamda_c = 2.*a\n", + "Zte = n/(math.sqrt(1-((lamda_o/lamda_c)**2)))\n", + "#Since 1hp = 746 watt = Pmax,\n", + "Pmax = 746\n", + "Emax = math.sqrt((Pmax*4*Zte)/(a*b))\n", + "\n", + "#Results\n", + "print \"Solution obtained in the textbook are incorrect as the value of a & b is taken wrong\"\n", + "print \"Peak value of electric field is\",round(Emax,3),\"V/m\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Solution obtained in the textbook are incorrect as the value of a & b is taken wrong\n", + "Peak value of electric field is 1139.724 V/m\n" + ] + } + ], + "prompt_number": 83 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.23, Page number 155" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate the breakdown power of an airfilled rectangular waveguide'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "a = 2.3 #length of rectangular waveguide(cms)\n", + "b = 1.0 #breadth of rectangular waveguide(cms)\n", + "f = 9.375*10**9 #frequency(Hz)\n", + "c = 3*10**10 #velocity of propagation(m/s)\n", + "\n", + "#Calculations\n", + "lamda_o = c/f\n", + "x = (1-((lamda_o/(2*a))**2))**0.5\n", + "Pbd = 597*a*b*x\n", + "\n", + "#Results\n", + "print \"Breakdown power =\",round(Pbd,3),\"W\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Breakdown power = 986.406 W\n" + ] + } + ], + "prompt_number": 35 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example 4.24, Page number 156" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "'''Calculate the breakdown power'''\n", + "\n", + "import math\n", + "\n", + "#Variable declaration\n", + "d = 5. #internal diameter(cms)\n", + "a = d/2\n", + "f = 9.*10**9 #frequency(Hz)\n", + "c = 3.*10**10 #velocity of propagation\n", + "\n", + "#Calculations\n", + "lamda_o = c/f\n", + "lamda_c = (math.pi*d)/1.841\n", + "fc = c/lamda_c\n", + "x = (1 - ((fc/f)**2))**0.5\n", + "Pbd = 1790.*a*a*x\n", + "\n", + "#Results\n", + "print \"Breakdown power =\",round((Pbd/1E+3),3),\"kW\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Breakdown power = 10.298 kW\n" + ] + } + ], + "prompt_number": 88 + } + ], + "metadata": {} + } + ] +}
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