//Fiber-optics communication technology, by Djafer K. Mynbaev and Lowell L. Scheiner //Example 11.3.1 //windows 7 //Scilab version-6.0.0 clc; clear ; //given Pin=0.1E-6;//Average input power in W lambda=1550;//Operating wavelength in nm R=1;//Responsivity of an MF-432 PIN photodiode Ip=R*Pin;//photocurrent in A e=1.6E-19;//Electrons value in Coulomb BWpd=2.5E+9;//Bandwidth of an MF-432 PIN photodiode in Hz Is=sqrt(2*e*Ip*BWpd); Isn=Is/sqrt(BWpd);//shot noise current in A/sqrt(Hz) Kb=1.38E-23;//Boltzman constant in J/K T=300;//Room temperature in K P=Kb*T; Rl=50E+3; x=(4*P)/Rl; It=sqrt(x*BWpd); Itn=It/sqrt(BWpd);//thermal noise current in A/sqrt(Hz) id=3E-9;//average dark noise current in A Id=sqrt(2*e*id*BWpd); Idn=Id/sqrt(BWpd);//dark noise current in A/sqrt(Hz) Inoise=sqrt(Is^2+It^2+Id^2);//RMS value of noise current for an MF-432 PIN photodiode in A mprintf("RMS value of noise current for an MF-432 PIN photodiode = %.1f nA", Inoise*1E+9);//Multiplication by 1e9 to convert unit from A to nA InoiseN=sqrt(Isn^2+Itn^2+Idn^2);//Bandwidth value of noise current for an MF-432 PIN photodiode in A/sqrt(Hz) mprintf("\nBandwidth value of noise current for an MF-432 PIN photodiode = %.2f x10^-4 nA/sqrt(Hz)", InoiseN*1E+13) //Multiplication by 1e12 to convert unit from A to pA