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  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Ch-3 : Microwave Network Analysis"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Page Number: 142 Example 3.4"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "from numpy import array, linalg, mat, set_printoptions\n",
      "\n",
      "#Given\n",
      "\n",
      "z=mat('[4 2 ;2 4]')\n",
      "I=mat('[1 0;0 1]') \n",
      "\n",
      "\n",
      "#Scattering matrix\n",
      "s=(z-I)*linalg.inv(z+I)\n",
      "set_printoptions(precision=3)\n",
      "print 'Scattering Matrix:\\n' ,s"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Scattering Matrix:\n",
        "[[ 0.524  0.19 ]\n",
        " [ 0.19   0.524]]\n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Page Number: 142 Example 3.5"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from math import sqrt, pi \n",
      "from cmath import exp\n",
      "#Given\n",
      "P=12.8e-3  #W\n",
      "l=3  #cm\n",
      "lamb=4.2  #cm\n",
      "vswr=2.2 \n",
      "jfi=1J*4.49 \n",
      "\n",
      "#ap\n",
      "ap=sqrt(2*P) \n",
      "\n",
      "#Phase shift\n",
      "bl=(2*pi*l)/lamb \n",
      "#bp\n",
      "bp=(ap*(vswr-1))/(vswr+1) \n",
      "\n",
      "a=ap*exp(jfi) \n",
      "b=bp*exp(jfi) \n",
      "print 'Required Waves:\\n{:.3}'.format(a),'\\n{:.3}'.format(b)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Required Waves:\n",
        "(-0.0353-0.156j) \n",
        "(-0.0132-0.0585j)\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Page Number: 143 Example 3.6"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      " from math import log10\n",
      "#Given\n",
      "S11=0.10 \n",
      "S12=0.90 \n",
      "A12=-45 \n",
      "S21=0.90 \n",
      "A21=45 \n",
      "S22=0.3 \n",
      "\n",
      "#(i) Network is reciprocal\n",
      "if(A12==A21):\n",
      "    print 'Network is reciprocal' \n",
      "else:\n",
      "    \n",
      "    print 'Network is not reciprocal' \n",
      "\n",
      "\n",
      "#(ii) Network is lossles\n",
      "x=(S11**2)+(S12**2) \n",
      "if(x==1):\n",
      "    print 'Network is lossless' \n",
      "else:\n",
      "    \n",
      "    print 'Network is not lossless' \n",
      "\n",
      "\n",
      "#(iii)Return loss\n",
      "T=S11-((S12*S21)/(1+S22)) \n",
      "Tm=-T  #mod of T\n",
      "L=-20*log10(Tm) \n",
      "print 'Return Loss: %0.3f'%L,'dB'"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Network is not reciprocal\n",
        "Network is not lossless\n",
        "Return Loss: 5.629 dB\n"
       ]
      }
     ],
     "prompt_number": 17
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Page Number: 163 Example 3.12"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#Given\n",
      "S11=0.6 \n",
      "S12=0.045 \n",
      "S21=2.5 \n",
      "S22=0.50 \n",
      "TS=0.5 \n",
      "TL=0.4 \n",
      "Z0=50  #ohm\n",
      "Vrms=10  #V\n",
      "\n",
      "#(i) Gain Parameters\n",
      "#(i)Reflection coefficients of input and output\n",
      "Tin=S11+((S12*S21*TL)/(1-(S22*TL))) \n",
      "Tout=S22+((S12*S21*TS)/(1-(S22*TS))) \n",
      "\n",
      "#Transducer Gain\n",
      "x=(1-(TS)**2)/((1-(S11*TS))**2) \n",
      "y=(S21*S21) \n",
      "z=(1-(TL)**2)/((1-(Tout*TL))**2) \n",
      "GT=x*y*z \n",
      "print 'Transducer Gain: %0.3f'%GT\n",
      "\n",
      "#Available Power Gain\n",
      "z1=1-(Tout)**2 \n",
      "GA=(x*y)/z1 \n",
      "print 'Available power Gain: %0.3f'%GA\n",
      "\n",
      "#Power Gain\n",
      "z2=1-(Tin)**2 \n",
      "GP=(x*y)/z2 \n",
      "print 'Power Gain: %0.3f'%GP\n",
      "\n",
      "#(ii) Power levels\n",
      "#Power available at source\n",
      "Pavs=(sqrt(2)*Vrms)**2/(8*Z0) \n",
      "print 'Power available at source: %0.3f'%Pavs,'W'\n",
      "\n",
      "Pl=9.4*Pavs \n",
      "#Power available at input\n",
      "Pin=Pl/13.5 \n",
      "print 'Power available at input: %0.3f'%Pin,'W'\n",
      "\n",
      "#(iii) VSWRs\n",
      "M1=Pin/Pavs \n",
      "M2=Pl/(9.6*Pavs) \n",
      "\n",
      "Tin1=sqrt(1-M1) \n",
      "Tout1=sqrt(1-M2) \n",
      "\n",
      "vswrin=(1+Tin1)/(1-Tin1) \n",
      "print 'Input VSWR: %0.3f'%vswrin\n",
      "vswrout=(1+Tout1)/(1-Tout1) \n",
      "print 'Output VSWR: %0.3f'%vswrout\n",
      "\n",
      "#Calculations for gain are done wrong in book, hence answers dont match"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Transducer Gain: 13.553\n",
        "Available power Gain: 14.291\n",
        "Power Gain: 16.803\n",
        "Power available at source: 0.500 W\n",
        "Power available at input: 0.348 W\n",
        "Input VSWR: 3.455\n",
        "Output VSWR: 1.337\n"
       ]
      }
     ],
     "prompt_number": 20
    }
   ],
   "metadata": {}
  }
 ]
}