MIMO DCO-OFDM在可见光通信系统中的误码率仿真matlab代码、

以下是MIMO DCO-OFDM在可见光通信系统中的误码率仿真matlab代码：

clear all;
close all;
clc;

%% Parameters
N = 64; % FFT size
CP = 16; % Cyclic Prefix
M = 4; % Modulation order
L = 4; % Number of LEDs
nTx = 2; % Number of transmitters
nRx = 2; % Number of receivers
snr = 0:2:20; % Signal to noise ratio
numIter = 10^3; % Number of iterations
ber = zeros(length(snr), 1); % Bit error rate

%% Channel matrix for MIMO
H = (randn(nRx, nTx, L)+1i*randn(nRx, nTx, L))/sqrt(2);

%% LED positions
ledPos = [0 0; 0 1; 1 0; 1 1];

%% Generate random bit stream
txBits = randi([0 1], nTx*N*log2(M), 1);

%% Modulation
txMod = qammod(txBits, M);

%% Serial to Parallel
txS2P = reshape(txMod, [], nTx);

%% OFDM
txOFDM = ifft(txS2P, N, 2);

%% Add Cyclic Prefix
txCP = [txOFDM(:, end-CP+1:end) txOFDM];

%% Parallel to Serial
txP2S = reshape(txCP, [], 1);

%% LED intensity levels
ledInt = sqrt(mean(abs(txP2S).^2));

%% LED positions
ledPos = [0 0; 0 1; 1 0; 1 1];

%% Channel matrix for MIMO
H = (randn(nRx, nTx, L)+1i*randn(nRx, nTx, L))/sqrt(2);

%% Channel matrix for VLC
Hv = zeros(nRx, L);
for i=1:nRx
    for j=1:L
        Hv(i,j) = sqrt(sum((ledPos(j,:)-[i-1,0]).^2))^(-3/2);
    end
end

%% Transmit through VLC channel
rxVLC = Hv*diag(ledInt)*txP2S;

%% Receive through MIMO channel
rxMIMO = zeros(N+CP, nRx);
for i=1:L
    rxMIMO(:,i) = awgn(H(:,:,i)*rxVLC(:,i), snr(1), 'measured');
end

%% Remove cyclic prefix
rxNoCP = rxMIMO(CP+1:end,:);

%% FFT
rxFFT = fft(rxNoCP, N, 1);

%% Parallel to serial
rxP2S = reshape(rxFFT, [], 1);

%% Demodulation
rxDemod = qamdemod(rxP2S, M);

%% Calculate BER
ber(1) = sum(xor(rxDemod, txBits))/length(txBits);

%% Repeat for different SNR values
for i=2:length(snr)
    for j=1:numIter
        %% Generate random bit stream
        txBits = randi([0 1], nTx*N*log2(M), 1);

        %% Modulation
        txMod = qammod(txBits, M);

        %% Serial to Parallel
        txS2P = reshape(txMod, [], nTx);

        %% OFDM
        txOFDM = ifft(txS2P, N, 2);

        %% Add Cyclic Prefix
        txCP = [txOFDM(:, end-CP+1:end) txOFDM];

        %% Parallel to Serial
        txP2S = reshape(txCP, [], 1);

        %% LED intensity levels
        ledInt = sqrt(mean(abs(txP2S).^2));

        %% Transmit through VLC channel
        rxVLC = Hv*diag(ledInt)*txP2S;

        %% Receive through MIMO channel
        rxMIMO = zeros(N+CP, nRx);
        for k=1:L
            rxMIMO(:,k) = awgn(H(:,:,k)*rxVLC(:,k), snr(i), 'measured');
        end

        %% Remove cyclic prefix
        rxNoCP = rxMIMO(CP+1:end,:);

        %% FFT
        rxFFT = fft(rxNoCP, N, 1);

        %% Parallel to serial
        rxP2S = reshape(rxFFT, [], 1);

        %% Demodulation
        rxDemod = qamdemod(rxP2S, M);

        %% Calculate BER
        ber(i) = ber(i) + sum(xor(rxDemod, txBits))/length(txBits);
    end
    ber(i) = ber(i)/numIter;
end

%% Plot BER vs SNR
figure;
semilogy(snr, ber, 'b-o');
xlabel('SNR (dB)');
ylabel('BER');
title('MIMO DCO-OFDM in VLC System');
grid on;