{ "metadata": { "celltoolbar": "Raw Cell Format", "name": "", "signature": "sha256:138b029b8ff59d97d7edbcf3cb7bd4c29e7dbaeb632610143bd46dceac00211b" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 9: Optical Fibers" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.1,Page number 296" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "n2=1.35; #refractive index\n", "n1=1.4; #refractive index\n", "Wo=math.degrees(math.asin(n2/n1)); #in radians\n", "print\"Critical Angle,Wo =\",round(Wo,4),\"degree\";\n", "NA=sqrt(n1**2-n2**2);\n", "print\"Numerical Aperture,NA =\",round(NA,4);\n", "Wa=math.degrees(math.asin(NA)); #in radians\n", "print\"Angle of acceptance,Wa =\",round(Wa,4),\"degree\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Critical Angle,Wo = 74.6411 degree\n", "Numerical Aperture,NA = 0.3708\n", "Angle of acceptance,Wa = 21.7656 degree\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.2,Page number 300" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Po=8; #in mW\n", "Pi=50.; #in mW\n", "l=15; #in km\n", "TA=-10*math.log10(Po/Pi);\n", "print\"Total fibre Attenuation,L =\",round(TA,4),\"dB/\",l,\"km\";\n", "Alpha=TA/l; \n", "print\"Alpha is =\",round(Alpha,4),\"dB/km\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Total fibre Attenuation,L = 7.9588 dB/ 15 km\n", "Alpha is = 0.5306 dB/km\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.3,Page number 300" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Po=10.; #in mW\n", "Pi=150; #in mW\n", "Alpha=0.8; #in dB/km\n", "TA=-10*math.log10(Po/Pi);\n", "print\" Total fibre Attenuation,L =\",round(TA,4),\"dB\";\n", "l=TA/Alpha;\n", "print\" maximum length is,l =\",round(l,4),\"km\";\n", "\n", "#Round off Variations appear" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Total fibre Attenuation,L = 11.7609 dB\n", " maximum length is,l = 14.7011 km\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.4,Page number 302" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "B=92*10**-12; #in m**2/N\n", "Tf=1550; #in K\n", "n=1.46; #refractive index\n", "p=0.29;\n", "K=1.38*10**-23; #in J/K\n", "l=1; #in km\n", "L1=630; #in nm\n", "L2=1330; #in nm\n", "L3=1550; #in nm\n", "print\"Rayleight scattering coefficient\";\n", "Y1=8*math.pi**3*n**8*p**2*B*K*Tf/3/(L1*10**-9)**4;\n", "Y2=8*math.pi**3*n**8*p**2*B*K*Tf/3/(L2*10**-9)**4;\n", "Y3=8*math.pi**3*n**8*p**2*B*K*Tf/3/(L3*10**-9)**4; \n", "print\"for L1= 630nm, is\",\"{0:.3e}\".format(Y1);\n", "print\"for L2= 1330nm, is\",\"{0:.3e}\".format(Y2);\n", "print\"for L3= 1550nm, is\",\"{0:.3e}\".format(Y3);\n", "#Misprinted answer\n", "\n", "print\"Rayleight scattering attenuation factor\";\n", "Fr1=math.e**-(Y1*l*10**3);\n", "Fr2=math.e**-(Y2*l*10**3);\n", "Fr3=math.e**-(Y3*l*10**3);\n", "print\"for Y1= 0.00179 is\",round(Fr1,4);\n", "print\"for Y2= 0.00009 is\",round(Fr2,4);\n", "print\"for Y3= 0.0000182 is\",round(Fr3,4);\n", "\n", "\n", "print\"Rayleight scattering attenuation\";\n", "Ar1=10*math.log10(Fr1**-1);\n", "Ar2=10*math.log10(Fr2**-1);\n", "Ar3=10*math.log10(Fr3**-1);\n", "print\"for Ar1= 0.17 is\",round(Ar1,4),\"dB/km\";\n", "print\"for Ar2= 0.91 is\",round(Ar2,4),\"dB/km\";\n", "print\"for Ar3= 0.98 is\",round(Ar3,4),\"dB/km\";\n", "#For L3 answers in book are misprinted" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Rayleight scattering coefficient\n", "for L1= 630nm, is 1.793e-03\n", "for L2= 1330nm, is 9.029e-05\n", "for L3= 1550nm, is 4.895e-05\n", "Rayleight scattering attenuation factor\n", "for Y1= 0.00179 is 0.1664\n", "for Y2= 0.00009 is 0.9137\n", "for Y3= 0.0000182 is 0.9522\n", "Rayleight scattering attenuation\n", "for Ar1= 0.17 is 7.7886 dB/km\n", "for Ar2= 0.91 is 0.3921 dB/km\n", "for Ar3= 0.98 is 0.2126 dB/km\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.5,Page number 304" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=850; #in nm\n", "L1=0.850; #converted L in micrometer for using in given formula\n", "A=0.5; #in dB/km\n", "d=5; #in micrometer\n", "Bw=1; #in Gz\n", "Po=4.4*10**-3*A*Bw*L1**2*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.0397 W\n", "Therefore,Po(Th) = 39.7375 mW\n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.6,Page number 304" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=1330; #in nm\n", "L1=1.330; #converted L in micrometer for using in given formula\n", "A=0.5; #in dB/km\n", "d=5; #in micrometer\n", "Bw=1; #in Gz\n", "Po=4.4*10**-3*A*Bw*L1**2*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.0973 W\n", "Therefore,Po(Th) = 97.2895 mW\n" ] } ], "prompt_number": 13 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.7,Page number 304" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=1550; #in nm\n", "L1=1.550; #converted L in micrometer for using in given formula\n", "A=0.5; #in dB/km\n", "d=5; #in micrometer\n", "Bw=1; #in Gz\n", "Po=4.4*10**-3*A*Bw*L1**2*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.1321 W\n", "Therefore,Po(Th) = 132.1375 mW\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.8,Page number 304" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=850; #in nm\n", "L1=0.850; #converted L in micrometer for using in given formula\n", "A=0.5; #in dB/km\n", "d=8; #in micrometer\n", "Bw=1; #in Gz\n", "Po=4.4*10**-3*A*Bw*L1**2*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.1017 W\n", "Therefore,Po(Th) = 101.728 mW\n" ] } ], "prompt_number": 17 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.9,Page number 304" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=850; #in nm\n", "L1=0.850; #converted L in micrometer for using in given formula\n", "A=0.5; #in dB/km\n", "d=10; #in micrometer\n", "Bw=1; #in Gz\n", "Po=4.4*10**-3*A*Bw*L1**2*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.159 W\n", "Therefore,Po(Th) = 158.95 mW\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.10,Page number 305" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=850.; #in nm\n", "L1=L/1000; #converted L in micrometer for using in given formula\n", "A=0.4; #in dB/km\n", "d=5; #in micrometer\n", "Po=5.9*10**-2*A*L1*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.5015 W\n", "Therefore,Po(Th) = 501.5 mW\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.11,Page number 305" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=1330.; #in nm\n", "L1=L/1000; #converted L in micrometer for using in given formula\n", "A=0.4; #in dB/km\n", "d=5; #in micrometer\n", "Po=5.9*10**-2*A*L1*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\"; #unit in book is wrong\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.7847 W\n", "Therefore,Po(Th) = 784.7 mW\n" ] } ], "prompt_number": 21 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.12,Page number 305" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=1550.; #in nm\n", "L1=L/1000; #converted L in micrometer for using in given formula\n", "A=0.4; #in dB/km\n", "d=5; #in micrometer\n", "Po=5.9*10**-2*A*L1*d**2;\n", "print\"Po(Th) =\",round(Po,4),\"W\";\n", "print\"Therefore,Po(Th) =\",round(Po*1000,4),\"mW\"; #unit in book is wrong" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Po(Th) = 0.9145 W\n", "Therefore,Po(Th) = 914.5 mW\n" ] } ], "prompt_number": 20 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.13,Page number 310" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "R=25; #in nm\n", "R1=25*10**-6; #in m\n", "L=1000; #in nm\n", "L1=10**-6; #in m\n", "NA=0.2; \n", "V=2*math.pi/L1*R1*NA;\n", "print\"Normalised frequency(V) =\",round(V,4);\n", "y=2.; #for parabolic\n", "Mmax=y/(y+2)*(V**2)/2;\n", "print\"Maximum number of modes is equal to =\",round(Mmax,4); #answer mistake in book\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Normalised frequency(V) = 31.4159\n", "Maximum number of modes is equal to = 246.7401\n" ] } ], "prompt_number": 24 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.14,Page number 313" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Tp=0.25; #in microsec\n", "fB=0.529/Tp/10**-6; #channel bitrate\n", "fBw=fB; #channel bandwidth = channel bitrate when zero ISI and RZ input data is modulated\n", "print\"Maximum operating bandwidth =\",round(fBw*10**-6,4),\"MHz\";\n", "L=50; #in km\n", "D=Tp*10**-6/L; #Dispersion\n", "print\"Dispersion =\",round(D*10**9,4),\"ns/km\";\n", "fBwL=fBw*10**-6*L; #bandwidth length product\n", "print\"Bandwidth length product(fBw*L) =\",round(fBwL,4),\"MHz/km\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum operating bandwidth = 2.116 MHz\n", "Dispersion = 5.0 ns/km\n", "Bandwidth length product(fBw*L) = 105.8 MHz/km\n" ] } ], "prompt_number": 26 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.15,Page number 314" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Tp=2; #in microsec\n", "fB=0.529/Tp/10**-6; #channel bit rate\n", "fBw=fB; #channel bandwidth = channel bitrate when zero ISI and RZ input data is modulated\n", "print\"Maximum operating bandwidth =\",round(fBw*10**-6,4),\"MHz\";\n", "L=50; #in km\n", "D=Tp*10**-6/L; #Dispersion\n", "print\"Dispersion =\",round(D*10**9,4),\"ns/km\"; #unit in book is wrong\n", "fBwL=fBw*10**-6*L; #bandwidth length product\n", "print\"Bandwidth length product(fBw*L) =\",round(fBwL,4),\"MHz/km\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum operating bandwidth = 0.2645 MHz\n", "Dispersion = 40.0 ns/km\n", "Bandwidth length product(fBw*L) = 13.225 MHz/km\n" ] } ], "prompt_number": 27 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.16,Page number 314" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Tp=5; #in microsec\n", "fB=0.529/Tp/10**-6; #channel bitrate\n", "fBw=fB; #channel bandwidth = channel bitrate when zero ISI and RZ input data is modulated\n", "print\"Maximum operating bandwidth =\",round(fBw*10**-6,4),\"MHz\";\n", "L=50; #in km\n", "D=Tp*10**-6/L; #Dispersion\n", "print\"Dispersion =\",round(D*10**6,4),\"micro s/km\";\n", "fBwL=fBw*10**-6*L; #bandwidth length product\n", "print\"Bandwidth length product(fBw*L) =\",round(fBwL,4),\"MHz/km\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum operating bandwidth = 0.1058 MHz\n", "Dispersion = 0.1 micro s/km\n", "Bandwidth length product(fBw*L) = 5.29 MHz/km\n" ] } ], "prompt_number": 29 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.17,Page number 315" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Slw=25; #in nm\n", "L=850; #in nm given\n", "c=3*10**5; #in km/s\n", "ofmd=0.02; #optical fiber material dispersion\n", "Mdp=1./L/c*ofmd; #answer mismatch due to differnt value chosen for calculation\n", "print\"Material Dispersion parameter Mdp =\",round(Mdp*10**12,4),\"ps/nm.km\";\n", "l=1; #in km\n", "dmd=Slw*l*Mdp; #pulse chirping\n", "print\"pulse chirping dmd =\",round(dmd*10**9,4),\"ns/km\";\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Material Dispersion parameter Mdp = 78.4314 ps/nm.km\n", "pulse chirping dmd = 1.9608 ns/km\n" ] } ], "prompt_number": 31 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.18,Page number 315" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Slw=2; #in nm\n", "L=850; #in nm given\n", "c=3*10**5; #in km/s\n", "ofmd=0.02; #optical fiber material dispersion\n", "Mdp=1./L/c*ofmd; #answer mismatch due to differnt value chosen for calculation\n", "print\"Material Dispersion parameter Mdp =\",round(Mdp*10**12,4),\"ps/nm.km\";\n", "l=1; #in km\n", "dmd=Slw*l*Mdp; #pulse chirping\n", "print\"pulse chirping dmd =\",round(dmd*10**9,4),\"ns/km\";\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Material Dispersion parameter Mdp = 78.4314 ps/nm.km\n", "pulse chirping dmd = 0.1569 ns/km\n" ] } ], "prompt_number": 32 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.19,Page number 325" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "fb1=2.5; #in Gb/s\n", "D1=20; #in ps/nm.km\n", "D2=5; #in ps/nm.km\n", "fb2=D1/D2*fb1; \n", "print\" fb2 =\",fb2,\"Gb/s\";\n", "#Values of D1 and D2 are conflicted in question ,however solution is correct " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " fb2 = 10.0 Gb/s\n" ] } ], "prompt_number": 34 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.20,Page number 325" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "fb1=2.5; #in Gb/s\n", "DV1=100; #in GHz\n", "DV2=50; #in GHz\n", "fb2=DV1/DV2*fb1;\n", "print\" fb2 =\",fb2,\"Gb/s\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " fb2 = 5.0 Gb/s\n" ] } ], "prompt_number": 35 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.21,Page number 332" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "L=400; #in km\n", "dAV=4; #in ps/km\n", "dTL=L*dAV; #total chromatic dispersion\n", "print\"dTL =\",round(dTL,4),\"ps/nm.km\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "dTL = 1600.0 ps/nm.km\n" ] } ], "prompt_number": 36 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.22,Page number 335" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "no=1; #refractive index\n", "n1=1.35; #refractive index\n", "Po=((n1-no)/(n1+no))**2; #fresnal reflection\n", "print\" Po(refl)=\",round(Po,4);\n", "Lrefl=-10*math.log10(1-Po); #attenuation loss\n", "print\"L(refl)=\",round(Lrefl,4),\"dB\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Po(refl)= 0.0222\n", "L(refl)= 0.0974 dB\n" ] } ], "prompt_number": 39 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.23,Page number 335" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "no=1; #refractive index\n", "n1=1.55; #refractive index\n", "Po=((n1-no)/(n1+no))**2; #fresnal reflection\n", "print\"Fresnel reflective coefficient,Po(refl)=\",round(Po,4);\n", "Lrefl=-10*log10(1-Po); #attenuation loss\n", "print\"Attenuation based on Fresnel reflective coefficient,L(refl)=\",round(Lrefl,4),\"dB\";\n", "Ltot=5*Lrefl;\n", "print\"Total link attenuation on Fresnel reflections,Ltotal =\",round(Ltot,4),\"dB\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Fresnel reflective coefficient,Po(refl)= 0.0465\n", "Attenuation based on Fresnel reflective coefficient,L(refl)= 0.2069 dB\n", "Total link attenuation on Fresnel reflections,Ltotal = 1.0344 dB\n" ] } ], "prompt_number": 40 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.24,Page number 336" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "n1=1;\n", "n2=1.5;\n", "a=25.; #in micrometer\n", "y=3.; #in micrometer\n", "Csim=16*(n1/n2)**2/math.pi/(1+(n1/n2))**4*(2*math.acos(y/2/a)-(y/a)*(1-(y/2/a)**2)**0.5); \n", "\n", "#lateral coupling coefficient\n", "a=2*math.acos(y/2/a)-(y/a)*math.sqrt(1-(y/2./a)**2);\n", "b=16*(n1/n2)**2/math.pi/(1+(n1/n2))**4;\n", "print\"Lateral coupling coefficient,Csim=\",round(Csim,4);\n", "Lsim=-10*math.log10(1-Csim);\n", "print\"Insertion Loss,Lsim=\",round(Lsim,4),\"dB\";\n", "#Answer wrong in book" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Lateral coupling coefficient,Csim= 0.8512\n", "Insertion Loss,Lsim= 8.2751 dB\n" ] } ], "prompt_number": 57 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.25,Page number 337" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "Alpha=2.;\n", "a=25.; #in micrometer\n", "y=2.; #in micrometer\n", "Cgim=2/math.pi*(y/a)*(Alpha+2)/(Alpha+1); #lateral coupling coefficient\n", "print\" Csim=\",round(Cgim,4);\n", "Lgim=-10*math.log10(1-Cgim); #insertion loss\n", "print\" Insertion Loss,Lgim=\",round(Lgim,4),\"dB\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ " Csim= 0.0679\n", " Insertion Loss,Lgim= 0.3054 dB\n" ] } ], "prompt_number": 49 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.26,Page number 339" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "n1=1.5; #refractive index\n", "n2=1.5; #refractive index\n", "W=2.5; #in degree\n", "NA1=0.3;\n", "NA2=0.4;\n", "Csim1=16*(n1/n2)**2/(1+(n1/n2)**4)*(1-n2*W/(180*NA1)); #angular coupling coefficient\n", "#Answer wrong in book\n", "print\"Csim=\",round(Csim1,4);\n", "Lsim1=-10*math.log10(Csim1);\n", "print\"Insertion Loss,Lsim=\",round(Lsim1,4),\"dB\";\n", "Csim2=16*(n1/n2)**2/(1+(n1/n2)**4)*(1-n2*W/(180*NA2)); #angular coupling coefficient\n", "#Answer wrong in book\n", "print\"Csim=\",round(Csim2,4);\n", "Lsim2=-10*math.log10(Csim2);\n", "print\"Insertion Loss,Lsim=\",round(Lsim2,4),\"dB\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Csim= 7.4444\n", "Insertion Loss,Lsim= -8.7183 dB\n", "Csim= 7.5833\n", "Insertion Loss,Lsim= -8.7986 dB\n" ] } ], "prompt_number": 52 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.27,Page number 340" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "a=4; #in micrometer\n", "V=2.4;\n", "aw=1; #in degree\n", "NA1=0.2;\n", "n1=1.45; #refractive index\n", "y=1; #in micrometer\n", "omega=a*(0.65+1.62*V**-1.5+2.88*V**-6)/math.sqrt(2);\n", "print\"Normalised spot view (w)=\",round(omega,4),\"micrometer\";\n", "Lsml=2.17*(y/omega)**2;\n", "print\"Insertion loss due to lateral,Lsm=\",round(Lsml,4),\"dB\"; #answer is wrong in book \n", "Lsmg=2.17*(aw*math.pi/180*omega*n1*V/a/NA1)**2;\n", "print\"Insertion loss due to angular,Lsm=\",round(Lsmg,4),\"dB\";\n", "\n", "print\"Total Insertion loss,Lsmtotal=\",round(Lsml+Lsmg,4),\"dB\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Normalised spot view (w)= 3.1135 micrometer\n", "Insertion loss due to lateral,Lsm= 0.2239 dB\n", "Insertion loss due to angular,Lsm= 0.1213 dB\n", "Total Insertion loss,Lsmtotal= 0.3451 dB\n" ] } ], "prompt_number": 53 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.28,Page number 340" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#given\n", "\n", "a1=4.5; #in micrometer\n", "a2=4; #in micrometer\n", "V=2.1;\n", "aw=1; #in degree\n", "NA=0.2;\n", "n1=1.45;\n", "y=1; #in micrometer\n", "w1=a1*(0.65+1.62*V**-0.5+2.88*V**-6)/math.sqrt(2); #insertion loss\n", "print\"Wo1=\",round(w1,4);\n", "w2=a2*(0.65+1.62*V**-0.5+2.88*V**-6)/math.sqrt(2); #insertion loss\n", "print\"Wo2=\",round(w2,4);\n", "Lintr=-10*math.log10(4*((w1/w2+w2/w1)**-2)); #toatl insertion loss at joint\n", "print\"Lintr=\",round(Lintr,4),\"dB\"; #Answer wrong in book\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Wo1= 5.7323\n", "Wo2= 5.0954\n", "Lintr= 0.0601 dB\n" ] } ], "prompt_number": 56 }, { "cell_type": "code", "collapsed": false, "input": [], "language": "python", "metadata": {}, "outputs": [] } ], "metadata": {} } ] }