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 "metadata": {

  "name": "",

  "signature": "sha256:ad12bff96918abc5e35ecb69ed85dad3776e4014893a3bdddb23c1bfeff5820d"

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 "worksheets": [

  {

   "cells": [

    {

     "cell_type": "heading",

     "level": 1,

     "metadata": {},

     "source": [

      "Chapter11:STRIP LINES"

     ]

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg11.1.1:pg-495"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "#calculation of characteristic impedance Z0 of the line\n",

      "er=5.23 #relative dielectric constant of the board material\n",

      "h=7     #height from microstrip line to the ground in mils\n",

      "t=2.8   #thickness of the microstrip line in mils\n",

      "w=10    #width of the microstrip line in mils\n",

      "Z0=(87*(math.log((5.98*h)/(t+(0.8*w)))))/sqrt(er+1.41) \n",

      "print\"The characteristic impedance of the line(in ohms)is =\",round(Z0,2),\"ohms\" #calculation mistake in book"

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The characteristic impedance of the line(in ohms)is = 45.74 ohms\n"

       ]

      }

     ],

     "prompt_number": 13

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg11.2.1:pg-505"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "#(a) Calculate the required width w of the conducting strip in order to have a characteristic impedance of 50 ohms           \n",

      "erd=6          #relative dielectric constant of BeO\n",

      "d=4*(10**-3)   #thickness in meter\n",

      "Z0=50          #characteristic impedance in ohms\n",

      "w=(377*(d))/((sqrt(erd))*Z0) \n",

      "print\"The required width of the conducting strip(in metres)is =\",\"{:.3e}\".format(w),\"m\"\n",

      "\n",

      "#(b) Calculate the strip line capacitance\n",

      "ed=8.854*(10**-12)*erd \n",

      "d=4*(10**-3)        #thickness in meter\n",

      "C=(ed*round(w,5))/d #strip line capacitance\n",

      "C=C*(10**12)        #multiply C by 10**12 for converting it in pF/m\n",

      "print\"The strip line capacitance(in pF/m)is =\",round(C,1),\"pF/m\"\n",

      "\n",

      "#(c) Calculate the strip line inductance\n",

      "uc=4*math.pi*(10**-7) #permeability of the conductor\n",

      "d=4*(10**-3)          #thickness in meter\n",

      "L=(uc*d)/w \n",

      "L=L*(10**6)           #converting L in micro H/m\n",

      "print\"The strip line inductance(in uH/m)is =\",round(L,2),\"micro H/m\" \n",

      "\n",

      "#(d)Calculate the phase velocity of the wave in the parallel strip line\n",

      "c=3*(10**8)           #speed of light in meter/second\n",

      "vp=c/sqrt(erd) \n",

      "print\"The phase velocity of the wave in the parallel strip line(in m/s)is =\",\"{:.2e}\".format(vp),\"m/s\""

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The required width of the conducting strip(in metres)is = 1.231e-02 m\n",

        "The strip line capacitance(in pF/m)is = 163.5 pF/m\n",

        "The strip line inductance(in uH/m)is = 0.41 micro H/m\n",

        "The phase velocity of the wave in the parallel strip line(in m/s)is = 1.22e+08 m/s\n"

       ]

      }

     ],

     "prompt_number": 16

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg11.3.1:pg-507"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "#Determine the characteristic impedance of the coplanar strip line\n",

      "Pavg=250*(10**-3) #average power flowing in the positive z direction in watt\n",

      "Io=100*(10**-3)   #total peak current in ampere\n",

      "Z0=(2*Pavg)/(Io**2) \n",

      "print\"The characteristic impedance of the coplanar strip line(in ohms)is =\",int(round(Z0)),\"ohms\""

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The characteristic impedance of the coplanar strip line(in ohms)is = 50 ohms\n"

       ]

      }

     ],

     "prompt_number": 17

    },

    {

     "cell_type": "heading",

     "level": 2,

     "metadata": {},

     "source": [

      "Eg11.4.1:pg-508"

     ]

    },

    {

     "cell_type": "code",

     "collapsed": false,

     "input": [

      "import math\n",

      "#(a)Calculate the K factor\n",

      "er=2.56    #dielectric constant of the insulator(polystyrene)\n",

      "w=25.0     #strip width in mils\n",

      "t=14.0     #strip thickness in mils\n",

      "d=70       #shield depth in mils\n",

      "K=1.0/(1-(t/d)) \n",

      "print\"The K factor is =\",K\n",

      "\n",

      "#(b)Calculate the fringe capacitance\n",

      "Cf=round(((8.854*er)*(round((2*K*math.log(K+1)),3)-round(((K-1)*math.log((K**2)-1)),2))),)/round(math.pi,2)\n",

      "print\"The fringe capacitance(in pF/m)is =\",round(Cf,2),\"pF/m\" \n",

      "\n",

      "#(c) Calculate the characteristic impedance of the line\n",

      "Z0=94.15/((((w/d)*K)+(round(Cf,2)/(8.854*er)))*(sqrt(er))) \n",

      "print\"The characteristic impedance of the line(in ohms)is =\",round(Z0,3),\"ohms\"  #answer is wrong in book"

     ],

     "language": "python",

     "metadata": {},

     "outputs": [

      {

       "output_type": "stream",

       "stream": "stdout",

       "text": [

        "The K factor is = 1.25\n",

        "The fringe capacitance(in pF/m)is = 15.61 pF/m\n",

        "The characteristic impedance of the line(in ohms)is = 51.839 ohms\n"

       ]

      }

     ],

     "prompt_number": 20

    }

   ],

   "metadata": {}

  }

 ]

}