{ "metadata": { "name": "", "signature": "sha256:4930bebda7035fefc5221e84cdee44dfb2c772873b238e2ca2714c2de4369a09" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 11: Optical amplifires" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.1, Page Number: 397" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#variable declaration\n", "Vg = 2*10**8 #group velocity (m/s)\n", "h = 6.625*10**-34 #planks constant (J*s)\n", "C = 3*10**8 #free space velocity (m/s)\n", "Lam_bda = 1550*10**-9 #operating wave length(nm)\n", "V = C/Lam_bda #frequency (Hz)\n", "w = 5*10**-6 #width of optical amplifier (meters)\n", "d = 0.5*10**-6 #thickness of optical amplifier (meter)\n", "Ps = 10**-6 #optical signal of power\n", "\n", "#calculation\n", "Nph = Ps/(Vg*h*V*w*d) #photon density\n", "\n", "#result\n", "print \"The photon density Nph = \" ,round(Nph*1e-16,2),\"e+6 photons/m3\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The photon density Nph = 1.56 e+6 photons/m3\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.2, Page Number: 397" ] }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.2(a)" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#varible declaration\n", "I = 100.0*10**-3 #bias current (Amps)\n", "w = 3.0*10**-6 #active area width (meters)\n", "L = 500.0*10**-6 #amplifier lenght (meters)\n", "d = 0.3*10**-6 #active area thick ness(meters)\n", "q = 1.6*10**-19 #charge (coulombs)\n", "Tuo = 0.3 #The confinement factor\n", "a = 2*10**-20 #gain coefficient (square meter)\n", "J = I/(w*L) #3bias current density (Amp/squre meter)\n", "nth = 10**24 #threshold density (per cubic meter)\n", "Tuor = 10**-9; #Time constant (seconds)\n", "\n", "\n", "#calculation\n", "Rp = I/(q*d*w*L) # The pumping rate((electron/m3)/s)\n", "\n", "#result\n", "print \"The pumping rate Rp = \" , round(Rp*1e-33,2)*10**33,\" (electron/m3)/s\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The pumping rate Rp = 1.39e+33 (electron/m3)/s\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 3, "metadata": {}, "source": [ "Example 11.2(b)" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#varible declaration\n", "I = 100.0*10**-3 #bias current (Amps)\n", "w = 3.0*10**-6 #active area width (meters)\n", "L = 500.0*10**-6 #amplifier lenght (meters)\n", "d = 0.3*10**-6 #active area thick ness(meters)\n", "q = 1.6*10**-19 #charge (coulombs)\n", "Tuo = 0.3 #The confinement factor\n", "a = 2*10**-20 #gain coefficient (square meter)\n", "J = I/(w*L) #3bias current density (Amp/squre meter)\n", "nth = 10**24 #threshold density (per cubic meter)\n", "Tuor = 10**-9; #Time constant (seconds)\n", "\n", "\n", "#calculation\n", "Rp=I/(q*d*w*L) #The pumping rate((electron/m3)/s)\n", "g0 = Tuo*a*Tuor*(round(Rp*1e-33,2)*10**33-(nth/Tuor)) #The zero singal(1/cm)\n", "\n", "#result\n", "print \"The zero singal g0 = \" ,round(g0),\"1/m =\", round(g0/100,1),\"1/cm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The zero singal g0 = 2340.0 1/m = 23.4 1/cm\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.3, Page Number: 404" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#variable declaration\n", "Lambda_p = 980.0*10**-9 #pump wavelength(nm)\n", "Lambda_s = 1550.0*10**-9 #signal wavelength(nm)\n", "Pp_in = 30.0*10**-3 #input pump power (watts)\n", "G = 1.0*10**2 #gain\n", "\n", "#calculation\n", "Ps_in = (Lambda_p/Lambda_s)*Pp_in/(G-1) #maximum input power(W)\n", "Ps_out = Ps_in+(Lambda_p/Lambda_s)*Pp_in #maximum output power(W)\n", "Ps_out_db = 10*(math.log10(Ps_out*10**3)) #maximum output power(dBm)\n", "\n", "#result\n", "print \"The maximum input power = \" , round(Ps_in*10**6) , \"uW\"\n", "print \"The maximum output power = \" , round(Ps_out*10**3,1),\"mW\"\n", "print \"The maximum output power = \" , round(Ps_out_db,1),\"dBm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The maximum input power = 192.0 uW\n", "The maximum output power = 19.2 mW\n", "The maximum output power = 12.8 dBm\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.6, Page Number: 412" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#variable declarion\n", "Q = 6 #Q factor of 6\n", "\n", "#calculation\n", "OSNR = 0.5*Q*(Q+math.sqrt(2))\n", "OSNR_DB = 10*(math.log10(OSNR)) #The optical signal to noise ratio(dB)\n", "\n", "#result\n", "print \"The optical signal to noise ratio (OSNR) = \" ,round(OSNR,2),\"=\", round(OSNR_DB,1),\"dB\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The optical signal to noise ratio (OSNR) = 22.24 = 13.5 dB\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.7, Page Number: 413" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#variable declaration\n", "Lambda_p = 980*10**-9 #pump wavelength (meters)\n", "Lambda_s = 1540*10**-9 #signal wavelength (meters)\n", "Ps_out = 10*10**-3 #output signal power(mW)\n", "Ps_in = 10**-3 #input signal power(mW)\n", "\n", "#calculation\n", "Pp_in = (Lambda_s/Lambda_p)*(Ps_out-Ps_in) #pump power at input(mW)\n", "\n", "#result\n", "print \"Pump power = \" , round(Pp_in*10**3) ,\"mW\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Pump power = 14.0 mW\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.8, Page Number: 413" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#variable declaration\n", "P_ASE1 = -22 #ASE level (dBm)\n", "P_ASE2 = -16 #ASE level (dBm)\n", "Pout = 6 #amplified signal level (dBm)\n", "\n", "#calculation\n", "OSNR1 = Pout-P_ASE1 \n", "OSNR2 = Pout-P_ASE2 #The optical signal to noise ratio(dBm)\n", "\n", "#result\n", "print \"Optical SNR OSNR1 = \" , round(OSNR1) , \"dBm\"\n", "print \"Optical SNR OSNR2 = \" , round(OSNR2) , \"dBm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Optical SNR OSNR1 = 28.0 dBm\n", "Optical SNR OSNR2 = 22.0 dBm\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.9, Page Number: 414" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#variable declaration\n", "G1 = 10**(30/10) #gain(dB)\n", "G2 = 10**(20/10)\n", "\n", "#calculation\n", "Fpath1 = (((G1-1)/math.log(G1))**2)/G1 #noise penalty factor for G1\n", "fpath_db1=10*math.log10(Fpath1) #noise penalty factor(dB)\n", "Fpath2 = (((G2-1)/math.log(G2))**2)/G2 #noise penalty factor for G2\n", "fpath_db2=10*math.log10(Fpath2) #noise penalty factor(dB)\n", "\n", "#result\n", "print \"Noise penalty factor for G1 = \",round(fpath_db1,1),\"dB\"\n", "print \"Noise penalty factor for G2 = \",round(fpath_db2,1),\"dB\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Noise penalty factor for G1 = 13.2 dB\n", "Noise penalty factor for G2 = 6.6 dB\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 11.10, Page Number: 415" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "\n", "#variable declaration\n", "etta = 0.65 #quantum efficiency\n", "nsp = 2 #population inversion\n", "R =50 #load resistance(ohms)\n", "Lambda = 1550*10**-9 #oprating wavelength(meters)\n", "T = 300 #room temperature(kelvin)\n", "h = 6.625*10**-34 #planks constant(J*s)\n", "C = 3*10**8 #free space velocity(m/s)\n", "kB = 1.38*10**-23 #boltzmann's constant \n", "V = C/ Lambda #(Hz)\n", "q = 1.6*10**-19 #Charge (coulombs)\n", "\n", "#calculation\n", "Ps_in = kB*T*h*V/(R*nsp*(etta**2)*(q**2)) #maxiamum input optical power level(Watt)\n", "\n", "#result\n", "print \"Upper bound input otical power level <\",round(Ps_in*10**6,1),\"uW\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Upper bound input otical power level < 490.8 uW\n" ] } ], "prompt_number": 11 } ], "metadata": {} } ] }