From 7f60ea012dd2524dae921a2a35adbf7ef21f2bb6 Mon Sep 17 00:00:00 2001 From: prashantsinalkar Date: Tue, 10 Oct 2017 12:27:19 +0530 Subject: initial commit / add all books --- 3638/CH13/EX13.6/Ex13_6.sce | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 3638/CH13/EX13.6/Ex13_6.sce (limited to '3638/CH13/EX13.6/Ex13_6.sce') diff --git a/3638/CH13/EX13.6/Ex13_6.sce b/3638/CH13/EX13.6/Ex13_6.sce new file mode 100644 index 000000000..27102af8b --- /dev/null +++ b/3638/CH13/EX13.6/Ex13_6.sce @@ -0,0 +1,36 @@ +//Introduction to Fiber Optics by A. Ghatak and K. Thyagarajan, Cambridge, New Delhi, 1999 +//Example 13.6 +//OS=Windows XP sp3 +//Scilab version 5.5.2 +clc; +clear; +//given +Id=1e-9;//Dark current of a silicon PIN photodiode in A +P=500e-9;//Optical power in W +R=0.65;//Responsivity in A/W +Rl=1000;//Value of load resistor in Ohms +e=1.6e-19//Electronic charge in C +kB=1.38e-23;//Boltzmann constant in SI Units +Deltaf=100e6;//Detector bandwidth in Hz +T=300;//Missing data- Temperature in K + +I=R*P;//Signal current in A +mprintf("\n I=%.3f uA",I/1e-6)//Division by 10^(-6) to convert into uA +//Let the root mean square shot noise current be Ins +//The rms shot noise current due to signal is: +Ins=sqrt(2*e*I*Deltaf);//As the root mean square shot noise current is the square root of mean square shot noise current in A +mprintf("\n The rms shot noise current due to signal = %.2f nA",Ins/1e-9);//Division by 10^(-9) to convert into nA +//The answers vary due to round off error + +//The rms shot noise current due to dark current is: +Ins=sqrt(2*e*Id*Deltaf);//As the root mean square shot noise current is the square root of mean square shot noise current in A +mprintf("\n The rms shot noise current due to dark current = %.2f nA",Ins/1e-9);//Division by 10^(-9) to convert into nA + +//The rms shot thermal noise current is: +Ins=sqrt(4*kB*T*Deltaf/Rl);//As the root mean square shot noise current is the square root of mean square shot noise current in A +mprintf("\n The rms shot thermal noise current = %.2f nA",Ins/1e-9);//Division by 10^(-9) to convert into nA +//The answers vary due to round off error +SNR=((R*P)^2)*Rl/(4*kB*T*Deltaf);//Corresponding Signal-to-noise ratio +mprintf("\n SNR = %f",SNR);//The answers vary due to round off error +mprintf("\n SNR in dB = %f dB",10*log10(SNR));//For conversion to dB +//The answers vary due to round off error -- cgit