拉曼光纤放大器仿真代码matlab

以下是一个简单的拉曼光纤放大器仿真代码MATLAB，可以用来模拟拉曼放大器的增益和噪声。

%% Raman Amplifier Simulation

clear all;
close all;

%% Parameters
L = 100; % fiber length (km)
Pp = 1e-3; % pump power (W)
lambda_p = 980e-9; % pump wavelength (m)
lambda_s = 1550e-9; % signal wavelength (m)
B = 10e9; % signal bandwidth (Hz)
h = 6.626e-34; % Planck's constant (J.s)
c = 3e8; % speed of light (m/s)
n2 = 2.6e-20; % nonlinear index (m^2/W)
Aeff = 80e-12; % effective area (m^2)
alpha = 0.2; % fiber attenuation coefficient (dB/km)

%% Calculate Signal Power
Pin = 1e-3; % input signal power (W)
Pout = Pin*exp(-alpha*L/1e3); % output signal power (W)

%% Calculate Raman Gain
gamma = (n2*pi*c)/lambda_s/Aeff;
Gs = (Pp*h*gamma*L)/(lambda_p*B);

%% Calculate ASE Noise Power
F = 1.2; % noise figure (dB)
Gss = 10^(Gs/10);
Pase = (h*B*Gss*(exp(h*B/lambda_s/2)-1))/((exp(h*B/lambda_s)-1)*(F-1));

%% Plot Results
fprintf('Signal Power: %g mW\n',Pout*1e3);
fprintf('Raman Gain: %g dB\n',10*log10(Gs));
fprintf('ASE Noise Power: %g pW/Hz\n',Pase*1e12);

figure;
f = linspace(-B/2,B/2,1000);
Pnf = Pase*1e3./f;
plot(f/1e9,10*log10(Pnf));
xlabel('Frequency (GHz)');
ylabel('Noise Power Density (dBm/Hz)');
title('ASE Noise Power Density');

这个代码计算了拉曼光纤放大器的增益和噪声，并绘制了噪声功率密度的频率响应。需要注意的是，这个代码是一个简单的模型，没有考虑一些复杂的因素，如多段放大器、泵浦光功率分布、泵浦光与信号光的相互作用等等。如果需要更精确的模拟，需要使用更复杂的模型和算法。