{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "

Chpater 7: PERFORMANCE ANALYSIS OF DIGITAL COMMUNICATION SYSTEMS

" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.15, Page No 414" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\n", "#initialisation of variables\n", "T=1.0*10**-6 #ms\n", "A=10.0*10**-3\n", "N=1*10**-11\n", "\n", "#CALCULATIONS\n", "Eb=((A**2)*T)/2.0\n", "Epb=math.sqrt(Eb/N)\n", "Pb=(1.0/2)*math.erfc(Epb)*(1.0/4)\n", "\n", "#RESULTS\n", "print(\"Bit error probability = %.2f X 10^-4 \" %(Pb*(10**4)))\n", "print('Approximation error')" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Bit error probability = 1.96 X 10^-4 \n", "Approximation error\n" ] } ], "prompt_number": 44 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.16, Page No 420" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "Br=25*10**6 #bits/sec\n", "N=2*10**-20 #Power spectral density of noise\n", "A=1.0*10**-6\n", "Ps=1*10**-12 # Normalized power\n", "\n", "#CALCULATIONS\n", "Tb=1.0/Br\n", "Ps=(A**2)/2.0\n", "Pe=1.0/2*(math.erfc((0.6*Ps*Tb)/N))\n", "#RESULTS\n", "print(\"Average probability of bit error is Pe= %.2f X 10^-4 \" %(Pe*10))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Average probability of bit error is Pe= 1.98 X 10^-4 \n" ] } ], "prompt_number": 45 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.17, Page No 423" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#Find probability of error\n", "\n", "#initialisation of variables\n", "A=2.0\n", "N0=2.0*10**-4 #power sepctral density\n", "\n", "#CALCULATIONS\n", "Tmin=(6.76*N0)/4\n", "\n", "#RESULTS\n", "print(\"The min time for which the signal should be extended is Tmin= %.3f X 10^-3 msec \" %(Tmin*10**3))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The min time for which the signal should be extended is Tmin= 0.338 X 10^-3 msec \n" ] } ], "prompt_number": 46 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.20, Page No 428" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#The average carrier\n", "\n", "#initialisation of variables\n", "Pe=10**-4\n", "N0=2*10**10\n", "T=1.0/10**6\n", "\n", "#CALCULATIONS\n", "E=6.76*N0\n", "P=E/T\n", "Eb=8.5171*N0\n", "P2=Eb/T\n", "\n", "\n", "#RESULTS\n", "print(\"The average carrier = %.3f X 10^-3 mW \" %(P2/10**17))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The average carrier = 1.703 X 10^-3 mW \n" ] } ], "prompt_number": 47 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.21, Page No 430" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#The average carrier\n", "\n", "#initialisation of variables\n", "A=0.2*10**-3 #V\n", "T=2*10**-6\n", "N0=2*10**-15\n", "\n", "#CALCULATIONS\n", "Pe=(math.sqrt((A**2*T)/4*N0))\n", "\n", "#RESULTS\n", "print(\"The average carrier = %.3f X 10^-4 mW \" %(Pe*10**15))\n", "print(\"Approximation error\")" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The average carrier = 6.325 X 10^-4 mW \n", "Approximation error\n" ] } ], "prompt_number": 48 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.29, Page No 447" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "A=1.0\n", "N0=2.0*10**-5 #power sepctral density\n", "\n", "#CALCULATIONS\n", "T=((3.71**2)*2*N0)/(A**2)\n", "Br=1/T\n", "#Results\n", "print(\"Bit rate Br= %.2f k bits/sec\" %(Br/(10**3)))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Bit rate Br= 1.82 k bits/sec\n" ] } ], "prompt_number": 49 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.31, Page No 448" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "Pe=10.0**-4 #probability of error of PSK\n", "N0=2.0*10**-10\n", "Br=10**6 #Bit Rate\n", "\n", "\n", "#CALCULATIONS\n", "T=1.0/Br\n", "E=N0*6.76\n", "P=E/T\n", "Eb=8.5171*N0\n", "Pb=Eb/T\n", "#Results\n", "print(\"i) PSK system The required carrier power = %.2f mW\" %(P*10**3))\n", "print(\"ii) DPSK system The required carrier power = %.2f mW\" %(Pb*10**3))\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "i) PSK system The required carrier power = 1.35 mW\n", "ii) DPSK system The required carrier power = 1.70 mW\n" ] } ], "prompt_number": 50 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.32, Page No 450" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "A=0.2*10**-3 #V\n", "T=2*10**-6 #Sec\n", "N0=2*10**-15\n", "\n", "\n", "#CALCULATIONS\n", "x=math.sqrt((A**2*T)/(4*N0))\n", "Pe=(1.0/2)*math.erfc(x/math.sqrt(2.0))\n", "\n", "#Results\n", "print(\"Probability of error = %.2f X 10^-4\" %(Pe*10**4))\n", "#print(\"Channel Bandwidth = %.5f MHz\" %BW)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Probability of error = 7.83 X 10^-4\n" ] } ], "prompt_number": 51 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.36, Page No 453" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "Ap=1 #mV\n", "En=192.3 #mV\n", "Arms=707 #mV\n", "\n", "\n", "#CALCULATIONS\n", "Z=Arms/En\n", "Pe=1.0/2*(math.erfc(math.sqrt(2)*(Z/math.sqrt(2))))\n", "\n", "#Results\n", "print(\"Probability of error is %.7f \" %Pe)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Probability of error is 0.0000001 \n" ] } ], "prompt_number": 52 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 7.37, Page No 454" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#initialisation of variables\n", "Br=2.08*10**-6 #Bit Rate\n", "N0=2*10**-8\n", "\n", "#CALCULATIONS\n", "Eb=(math.sqrt(3.3))/(5*10**7) #Eb=bit energy\n", "Ps=Eb*Br\n", "BW=2*Br #Bandwidth\n", "Es=286.39*N0\n", "Ps2=(Es*Br)/2\n", "BW2=(2*Br)/4\n", "\n", "#Results\n", "print(\"i) BPSK THe transmission bandwidth = %.2f MHz\" %(BW*10**6)) \n", "print(\"ii) For 16 ary PSK THe transmission bandwidth = %.2f MHz\" %(BW2*10**6)) \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "i) BPSK THe transmission bandwidth = 4.16 MHz\n", "ii) For 16 ary PSK THe transmission bandwidth = 1.04 MHz\n" ] } ], "prompt_number": 53 } ], "metadata": {} } ] }