{ "metadata": { "name": "", "signature": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 01 : Antenna Principles" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.1 : page 1.42" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "from math import pi\n", "#given data :\n", "E=4.0 #in V/m\n", "Eta=120*pi #constant\n", "#Formula : E/H=Eta\n", "H=E/Eta #in A/m\n", "print \"Strength of magnetic field in free space = %0.4f A/m \" %H" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Strength of magnetic field in free space = 0.0106 A/m \n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.2 : page 1.42" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#given data :\n", "H=5.2 #in mA/m\n", "Eta=120*pi #constant\n", "#Formula : E/H=Eta\n", "E=H*10**-3*Eta #in V/m\n", "print \"Strength of Electric field in free space =\",round(E),\"V/m\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Strength of Electric field in free space = 2.0 V/m\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.3 : page 1.42" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#given data :\n", "I=20.0 #in A\n", "Rr=100.0 #in Ohm\n", "#Formula : Wr=I**2*R\n", "Wr=I**2*Rr #in W\n", "print \"Radiated power = %0.f kW \" %(Wr/1000) " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Radiated power = 40 kW \n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.4 : page 1.42" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import sqrt\n", "#given data :\n", "W=625.0 #in KW\n", "r=30.0 #in Km\n", "Erms=sqrt(90*W*1000)/(r*1000) #in V/m\n", "print \"Strength of Electric field at 30Km away = %0.f mV/m \" %(Erms*1000) " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Strength of Electric field at 30Km away = 250 mV/m \n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.6 : page 1.43" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#given data :\n", "le=50.0 #in m\n", "f=100.0 #in MHz\n", "lamda=300.0/(f) #in m\n", "Rr=(160*(pi)**2)*(le/lamda)**2 #in Ohm\n", "print \"Radiation Resistance = %0.2f Mohm \" %(Rr/10**6) \n", "#Note : Answer in the book is wrong" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Radiation Resistance = 0.44 Mohm \n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.7 : page 1.44" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#given data :\n", "l=30 #in m\n", "Irms=20 #in A\n", "f=1 #in MHz\n", "r=10 #in Km\n", "r=r*1000 #in m\n", "le=2*l/pi #in m\n", "lamda=300/(f) #in m\n", "Erms=120*pi*le*Irms/(lamda*r) #in V/m\n", "print \"Field strength at 10Km distance = %0.2e V/m \" %Erms \n", "#Note : Answer in the book is wrong" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Field strength at 10Km distance = 4.80e-02 V/m \n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.8 : page 1.44" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#given data :\n", "Rl=1.0 #in ohm\n", "#Formula : Rr=80*pi**2*(l/lamda)**2\n", "#Given l=lamda/10\n", "#l/lamda=1/10\n", "Rr=80*pi**2*(1.0/10)**2 #in Ohm\n", "print \"Radiation resistance = %0.2f Ohm \" %(Rr) \n", "Eta=Rr/(Rr+Rl) #Unitless\n", "print \"Antenna Efficiency = %0.2f %% \" %(Eta*100) " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Radiation resistance = 7.90 Ohm \n", "Antenna Efficiency = 88.76 % \n" ] } ], "prompt_number": 15 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.9 : page 1.44" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import sqrt\n", "#given data :\n", "r=100 #in Km\n", "W=100 #in KW\n", "Erms=sqrt(90*W*1000)/(r*1000) #in V/m\n", "print \"Strength of Electric Field = %0.2f V/m \" %Erms " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Strength of Electric Field = 0.03 V/m \n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.10 : page 1.44" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#given data :\n", "le=200.0 #in m\n", "Irms=200 #in A\n", "f=300 #in KHz\n", "r=10 #in Km\n", "c=3*10**8 #speed of light i m/s\n", "lamda=c/(f*1000) #in m\n", "Erms=120*pi*le*Irms/(lamda*r*10**3) #in V/m\n", "print \"Field strength at 10Km distance = %0.4f V/m\" %(Erms) \n", "Rr=(160*(pi)**2)*(le/lamda)**2 #in Ohm\n", "W=Irms**2*Rr #in Watts\n", "print \"Radiated Power = %0.2f MW \" %(W/10**6) \n", "#Note : Answer is wrong in the book. Unit of answer in the book is written mW instead of MW by mistake." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Field strength at 10Km distance = 1.5080 V/m\n", "Radiated Power = 2.53 MW \n" ] } ], "prompt_number": 21 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.11 : page 1.45" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#given data :\n", "#Formula : Rr=80*pi**2*(l/lamda)**2\n", "#Given l=lamda/60\n", "#l/lamda=1/60\n", "Rr=80*pi**2*(1.0/60)**2 #in Ohm\n", "print \"Radiation resistance = %0.3f Ohm \" %Rr " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Radiation resistance = 0.219 Ohm \n" ] } ], "prompt_number": 23 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.12 : page 1.45" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#given data :\n", "r=10.0 #in Km\n", "Erms=10.0 #in mV/m\n", "r1=20.0 #in Km\n", "#Formula : Erms=sqrt(90*W)/r #in V/m\n", "#Let swrt(90*W)=a\n", "a=Erms*r \n", "Erms1=a/r1 #in mV/m\n", "print \"Field strength at 20Km distance = %0.f mV/m \" %Erms1 " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Field strength at 20Km distance = 5 mV/m \n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Exa 1.13 : page 1.45" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from math import pi\n", "#given data :\n", "r=1.0 #in Km\n", "r=1*10**3 #in m\n", "l=1.0 #in m\n", "Irms=10.0 #in A\n", "f=5.0 #in MHz\n", "c=3*10**8 #speed of light i m/s\n", "lamda=c/(f*10**6) #in m\n", "le=2*l/pi #in m\n", "Erms=120*pi*le*Irms/(lamda*r) #in V/m\n", "print \"Field strength at 10Km distance = %0.4f V/m \" %Erms\n", "#Note : Answer in the book is wrong. Mistake during value putting." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Field strength at 10Km distance = 0.0400 V/m \n" ] } ], "prompt_number": 26 } ], "metadata": {} } ] }