{
"metadata": {
"celltoolbar": "Raw Cell Format",
"name": "",
"signature": "sha256:203945c2a904a6f0edf3cdf28ac6e63e0d37dadb3a95128dce91cd424eb43420"
},
"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
}
],
"metadata": {}
}
]
}