focreylight

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MATLAB CODE FOR LOSS DUE TO RAYLIGHT SCATTERING:

clc;

clear all;alpha0 = 1.7;

lamda0 = 0.85;x = [700:1:1700];

Ralpha = alpha0*((lamda0/0.7)^4);

for i = x(1,2):x(1,1001)i = i/1000;Ralpha = [Ralpha,alpha0*((lamda0/i)^4)];

i = i*1000;end

x = x/1000;

 plot(x,Ralpha,'r');xlabel(' wavelength (micro meter) -------->');ylabel(' Rayleigh scattering (dB/km) --------->');

grid;

lamda = input('enter the wavelength in micrometer at which loss is to be calculated = ');Ralpha = alpha0*((lamda0/lamda)^4);disp('rayleigh scattering at given wavelength(dB/km)is =');

disp(Ralpha);

SIMULATION RESULTS:

enter the wavelength in micrometer at which loss is to be calculated = 1.5

rayleigh scattering at given wavelength(dB/km)is =

0.1753

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MATLAB CODE FOR MODEFILED DAIMETER:

clc;

clear all;d=input('diameter of core in micrometer=');n1=input('index of core=');n2=input('index of cladding=');

%NA=((n1^2)-(n2^2))^(1/2);

 NA = 0.13;d=d*1000;% convert diameter micrometer to nanometer 

Lamda = input('operating Wavelength at which number of modes to be calculated in nanometer=');%800to 1600 nanometer 

Vnumber = pi*d*NA/Lamda;MFD = 2*(d/2)*(0.65+(1.619/(Vnumber^(3/2)))+2.879/(Vnumber^6));

MFD = round(MFD);

MFD = MFD/1000;%convert MFD to micrometer disp('mode field diameter in micrometer = ');

disp(MFD);

SIMULATION RESULTS:

diameter of core in micrometer=1

index of core=1index of cladding=1.2

operating Wavelength at which number of modes to be calculated in nanometer=1.5mode field diameter in micrometer =

0.6500

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CONCLUSION:

From the results of the simulations one can conclude that if one knows the wavelength then

through it we can find loss due to ray light scattering in dB/km in fiber. This value is same as theoretical

value. If we know the diameter of core in micrometer, index of core, index of cladding then we get the

value of operating Wavelength at which number of modes to be calculated in nanometer.

ACKNOWLEDGEMENT:

We would like to thank Prof. Dhaval Pujara, for all the necessary guidance and information for 

the simulation code. His suggestion on how to improve the contents and design has made a definite

impact on this report and finally we would like to thank our family and friends for their coordination.