{ "metadata": { "name": "", "signature": "sha256:2baa3eb0c199078d6675540c13fc8ca69d0c0eaa0d2eef907c98727dce3b6cde" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Ch-1 : Microwaves" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 12 Example 1.2" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "import cmath \n", "from math import pi\n", "#Given\n", "z0=50 #ohm\n", "zg=50 #ohm\n", "l=0.25 #m\n", "f=4e9 #hz\n", "zl=100 #ohm\n", "vg=10 #V\n", "w=2*pi*f #rad/sec\n", "c=3e8 #m/s\n", "\n", "#(i) Voltage and current at any point\n", "tg=(zg-z0)/(zg+z0) \n", "tl=(zl-z0)/(zl+z0) \n", "vi=z0*vg/(z0+zg) #V\n", "print 'Voltage at any point = %0.2f V' %(vi)\n", "ii=vg/(2*z0) #A\n", "print 'Current at any point = %0.2f A'%(ii) \n", "\n", "#(ii) Voltage at generator end\n", "#Taking z=1\n", "z=1 \n", "bet=w/c \n", "vz=(vg/2)*cmath.exp(-1J*bet*(z+l))*(1+(tl*cmath.exp(2*1J*bet*z))) #V\n", "print 'Voltage at generator end ={:.3f}'.format(vz),'V'\n", "iz=ii*cmath.exp(-1J*bet*(z+l))*(1-(tl*cmath.exp(2*1J*bet*z))) #A\n", "vz1=(vg/2)*cmath.exp(-1J*bet*(z+l))*(1+(tl*cmath.exp(2*1J*bet*z))) #V\n", "\n", "#Voltage at load end, z=0\n", "z11=0 \n", "vl=(vg/2)*cmath.exp(-1J*bet*l)*(1+(tl*cmath.exp(2*1J*bet*z11))) #V\n", "print 'Voltage at load end ={:.3f}'.format(vl),'V'\n", "\n", "#(iii) Reflection coefficient\n", "zx=0.25 \n", "tz=tl*cmath.exp(1J*2*bet*zx) \n", "print 'Reflection coefficient:{:.3f}'.format(tz) \n", "\n", "#(iv) VSWR\n", "p=(1+tl)/(1-tl) \n", "print 'VSWR:' ,p\n", "\n", "#(v) Average power delivered to the load\n", "vl=20/3 \n", "pl0=vl**2/(2*zl) #W\n", "print 'Average power delivered to the load = %0.2f W' %pl0" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Voltage at any point = 5.00 V\n", "Current at any point = 0.10 A\n", "Voltage at generator end =-0.833+4.330j V\n", "Voltage at load end =-3.333-5.774j V\n", "Reflection coefficient:-0.167-0.289j\n", "VSWR: 2.0\n", "Average power delivered to the load = 0.22 W\n" ] } ], "prompt_number": 41 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 14 Example 1.3" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import log \n", "#Given\n", "pm=3 \n", "pl=4 \n", "l=24 #cm\n", "l1=l/100 #m\n", "\n", "#Attenuation\n", "tin=(pm-1)/(pm+1) \n", "tl=(pl-1)/(pl+1) \n", "alp=(1/(2*l1))*log(tl/tin) #Np/m\n", "print 'Attenuation in the line = %0.2f'%alp,'Mp/m' " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Attenuation in the line = 0.38 Mp/m\n" ] } ], "prompt_number": 42 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 14 Example 1.4" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import sqrt \n", "#Given\n", "c=3e8 #m/s\n", "z0=200 #ohm\n", "zl=800 #ohm\n", "f=30e6 #hz\n", "\n", "#Characterstic impedance\n", "z00=sqrt(z0*zl) #ohm\n", "print 'Characterstic impedance = %0.2f ohm' %z00\n", "\n", "#Length of line\n", "lam=c/f #m\n", "l=lam/4 #m\n", "print 'Length of line = %0.2f m' %l" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Characterstic impedance = 400.00 ohm\n", "Length of line = 2.50 m\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 15 Example 1.5" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "l=1.2 #mH\n", "r=8 #ohm\n", "c=200e-12 #F\n", "\n", "#(i) Resonant frequency\n", "f0=(1/(2*pi))*sqrt(1/(l*c)) #hz\n", "print 'Resonant frequency:%0.2f'%f0,'Hz' \n", "\n", "#(ii) Impedance of circuit\n", "print 'Impedance of circuit:',r,'ohm' \n", "\n", "#(iii)Q factor of the circuit\n", "q=1/(2*pi*f0*c*r) \n", "print 'Q factor of the circuit:%0.2f'%q\n", "\n", "#(iv) Bandwidth\n", "df=f0/q #hz\n", "\n", "print 'Bandwidth:%0.2f' %df,'Hz'\n", "\n", "#The value of resonant frequency is calculated wrong in book\n", "#Hence Q factor and bandwidth, all these answers dont match" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Resonant frequency:10273.41 Hz\n", "Impedance of circuit: 8 ohm\n", "Q factor of the circuit:9682.46\n", "Bandwidth:1.06 Hz\n" ] } ], "prompt_number": 44 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: Example 1.6" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import cos, sin\n", "#Given\n", "c=3e8 #m/s\n", "le=25 #m\n", "zl=40+(1J*30) #ohm\n", "f=10e6 #hz\n", "cap=40e-12 #F\n", "l=300e-9 #H/m\n", "\n", "#Input impedance\n", "z0=sqrt(l/cap) #ohm\n", "zl1=zl/z0 \n", "lam=c/f #m\n", "bet=(2*pi*le)/lam #rad\n", "zin=((zl1*cos(bet))+(1J*sin(bet)))/(cos(bet)+(1J*zl1*sin(bet))) #ohm\n", "print 'Input impedance: {:.3f}'.format(zin), 'ohm'\n", "\n", "#Reflection coefficient\n", "t=(zl1-1)/(zl1+1) \n", "print 'Reflection coefficient:{:.3f}'.format(t)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Input impedance: 0.577-0.577j ohm\n", "Reflection coefficient:-0.295+0.307j\n" ] } ], "prompt_number": 46 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 16 Example 1.7" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import cmath \n", "#Given\n", "c=3e8 #m/s\n", "R=2.25 #ohm\n", "L=1e-9 #H/m\n", "C=1e-12 #F/m\n", "f=0.5e9 #hz\n", "G=0 \n", "w=2*pi*f #rad/sec\n", "\n", "#Characterstic impedance\n", "z0=cmath.sqrt((R+(1J*w*L))/(G+(1J*w*C))) #ohm\n", "print 'Characterstic impedance:{:.3f}'.format(z0),'ohm'\n", "\n", "#Propagation constant\n", "gam=cmath.sqrt((R+(1J*w*L))*(G+(1J*w*C))) \n", "print 'Propagation constant:{:.3f}'.format(gam)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Characterstic impedance:33.392-10.724j ohm\n", "Propagation constant:0.034+0.105j\n" ] } ], "prompt_number": 48 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 20 Example 1.8" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "c=3e8 #m/s\n", "f=3e9 #Hz\n", "ZL=50-(1J*100) #ohms\n", "Z0=50 #ohm\n", "#Wavelength\n", "lam=c/f \n", "print 'Wavelength:',lam*100, 'cm'\n", "\n", "#Normalized load impedance\n", "z=ZL/Z0 \n", "print 'Normalized load impedance:' ,z\n", "\n", "#From chart\n", "zin=0.45+(1J*1.2) \n", "yin=0.27-(1J*0.73) \n", "ZINN=Z0*zin \n", "print 'Line impedance:' ,ZINN,'ohm'\n", "YINN=yin/Z0 \n", "print 'Line admittance:',YINN, 'mho'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Wavelength: 10.0 cm\n", "Normalized load impedance: (1-2j)\n", "Line impedance: (22.5+60j) ohm\n", "Line admittance: (0.0054-0.0146j) mho\n" ] } ], "prompt_number": 49 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 22 Example 1.9" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "ZL=75+(1J*100) #ohms\n", "Z0=50 #ohm\n", "\n", "#Normalized load impedance\n", "z=ZL/Z0 \n", "print 'Normalized load impedance:' ,z\n", "\n", "#(i) 0.051*lam\n", "#From chart\n", "r=4.6 \n", "Zi1=r*Z0 \n", "print 'Input impedance at 0.051 lam:' ,Zi1,'ohm'\n", "\n", "#(ii) 0.102*lam\n", "r1=1.5-(1J*2) \n", "Zi2=r1*Z0 \n", "print 'Input impedance at 0.102 lam:' ,Zi2,'ohm'\n", " \n", "#(iii) 0.301*lam\n", "r2=0.22 \n", "Zi3=r2*Z0 \n", "print 'Input impedance at 0.301 lam:' ,Zi3, 'ohm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Normalized load impedance: (1.5+2j)\n", "Input impedance at 0.051 lam: 230.0 ohm\n", "Input impedance at 0.102 lam: (75-100j) ohm\n", "Input impedance at 0.301 lam: 11.0 ohm\n" ] } ], "prompt_number": 50 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 23 Example 1.10" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "ZL=15+(1J*20) #ohms\n", "Z0=50 #ohm\n", "\n", "#Normalized load impedance\n", "z=ZL/Z0 \n", "print 'Normalized load impedance:' ,z\n", "\n", "#From chart\n", "T=0.6 \n", "print 'Reflection coefficient:' ,T\n", "\n", "#VSWR\n", "p=4 \n", "print 'VSWR:' ,p" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Normalized load impedance: (0.3+0.4j)\n", "Reflection coefficient: 0.6\n", "VSWR: 4\n" ] } ], "prompt_number": 51 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 25 Example 1.11" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "Z0=50 #ohm\n", "p=2.4 \n", "\n", "#From chart\n", "zl=1.4+1J \n", "L=Z0*zl \n", "print 'Load:',L, 'ohm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Load: (70+50j) ohm\n" ] } ], "prompt_number": 52 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 26 Example 1.12" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "Z0=50 #ohm\n", "T=2.23 \n", "\n", "#From chart\n", "zl=2+1J \n", "ZLd=Z0*zl \n", "print 'Normalized impedance:',ZLd, 'ohm'\n", "\n", "#Impedance of device is by negating the real part\n", "imp=-(ZLd.real)+((ZLd.imag)*1J) \n", "print 'Impedance of device:' ,imp,'ohm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Normalized impedance: (100+50j) ohm\n", "Impedance of device: (-100+50j) ohm\n" ] } ], "prompt_number": 53 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 27 Example 1.13" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "p=3 \n", "m1=54 #cm\n", "m2=204 #cm\n", "\n", "#Point A\n", "print 'Point A' \n", "lam=4*(m2-m1) \n", "dA=0.083*lam \n", "L=m1-dA \n", "print 'Location of stub:',L, 'cm'\n", "IA=0.114*lam \n", "print 'Length:' ,IA, 'cm'\n", "\n", "#Point B\n", "print 'Point B' \n", "dB=0.083*lam \n", "IB=0.386*lam \n", "Lb=dB+m1 \n", "print 'Location of stub:',Lb, 'cm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Point A\n", "Location of stub: 4.2 cm\n", "Length: 68.4 cm\n", "Point B\n", "Location of stub: 103.8 cm\n" ] } ], "prompt_number": 54 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 30 Example 1.15" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given\n", "Z0=50 #ohm\n", "ZL=100 #ohms\n", "f=10e9 #Hz\n", "c=0.159e-12 #F\n", "\n", "#Normalized load impedance\n", "z=ZL/Z0 \n", "print 'Normalized load impedance:' ,z\n", "\n", "#From chart\n", "zin=0.4+(1J*0.55) \n", "ZINN=Z0*zin \n", "print 'Normalized impedance:',ZINN, 'ohm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Normalized load impedance: 2.0\n", "Normalized impedance: (20+27.5j) ohm\n" ] } ], "prompt_number": 55 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 42 Example 1.16" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#From given wave equation we can see\n", "w=1e9 #rad/sec\n", "bet=30 #rad/m\n", "c=3e8 #m/s\n", "u0=1 #let\n", "e0=1/(9e16) \n", "\n", "vp=w/bet #m/sec\n", "print 'Phase velocity:%0.2f' %vp,'m/s'\n", "\n", "e=1/(vp**2*u0) \n", "er=e/(e0*u0) \n", "print 'Dielectric constant:' ,er" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Phase velocity:33333333.33 m/s\n", "Dielectric constant: 81.0\n" ] } ], "prompt_number": 56 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 42 Example 1.17" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#Given\n", "c=3e8 #m/s\n", "f=10e9 #hz\n", "er=6 \n", "tandel=2e-4 \n", "\n", "vp=c/er #m/sec\n", "print 'Phase velocity: %0.f'%vp,'m/sec'\n", "al=(pi*f*tandel)/vp #Np/m\n", "print 'Attenuation constant: %0.3f'%al,'Np/m'\n", "\n", "#Answer for velocity is calculated wrong in book, hence answers dont match for both" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Phase velocity: 50000000 m/sec\n", "Attenuation constant: 0.126 Np/m\n" ] } ], "prompt_number": 59 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 43 Example 1.18" ] }, { "cell_type": "code", "collapsed": false, "input": [ " #Given\n", "er=2.2 \n", "n0=377 #ohm\n", "n2=n0/sqrt(er) #ohm\n", "n1=377 #ohm\n", "\n", "#Reflection coefficient\n", "t=(n2-n1)/(n2+n1) \n", "print 'Reflection coefficient: %0.2f'%t\n", "\n", "#Vswr\n", "#Taking mod of reflection coefficient\n", "t1=-t \n", "p=(1+t1)/(1-t1) \n", "print 'VSWR: %0.3f'%p" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Reflection coefficient: -0.19\n", "VSWR: 1.483\n" ] } ], "prompt_number": 62 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 43 Example 1.19" ] }, { "cell_type": "code", "collapsed": false, "input": [ " #Given\n", "sig=5 #mohm/m\n", "er=80*8.85e-12 \n", "eaz=0.1 \n", "u=1.26e-6 \n", "\n", "az=-log(0.1) \n", "#(i) Range at 25Khz\n", "f=25e3 #Khz\n", "w=2*pi*f #rad/sec\n", "a=w*(sqrt((u*er/2)*(sqrt(sig**2/(w**2*er**2)+1)-1))) \n", "z=az/a #m\n", "print 'Range at 25khz: %0.3f'%z, 'm'\n", "\n", "#(ii) Range at 25Mhz\n", "f1=25e6 #Mhz\n", "w1=2*pi*f1 #rad/sec\n", "a1=w1*(sqrt((u*er/2)*(sqrt(sig**2/(w1**2*er**2)+1)-1))) \n", "z1=az/a1 #m\n", "print 'Range at 25Mhz: %0.3f'%z1, 'm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Range at 25khz: 3.273 m\n", "Range at 25Mhz: 0.105 m\n" ] } ], "prompt_number": 63 } ], "metadata": {} } ] }