QPSK matlab 调制解调代码

% case1: AWGN Channel clear clc close all numSamplesPerSymbol=8; BitRate = 16000; BaudRate = BitRate/2; SymbolDuration = 1/BaudRate; SamplingFrequency= numSamplesPerSymbol * BaudRate; nIters = 20; LogEbN0=[0:10]; lenSIm=length(LogEbN0); % Symbol Repetition -- hTransmitFilter = ones(1,numSamplesPerSymbol); hReceiveFilter = hTransmitFilter; AvBER = zeros(1,lenSIm); % Symbol Repeitition for EbN0Index = 1:lenSIm for iters=1:nIters %The transmitter BitStreamLength = 10000; BitStream = rand(1, BitStreamLength) > 0.5; [BitStreamOne, BitStreamTwo ] = SerialToParallel( BitStream); [I_SymbolsTx, Q_SymbolsTx] = DQPSKEncoder(BitStreamOne, BitStreamTwo); [I_WaveformTx, Q_WaveformTx] = TransmitFilter(I_SymbolsTx, Q_SymbolsTx, ... hTransmitFilter, numSamplesPerSymbol ); % Power Calculation EbN0 = 10^( LogEbN0(EbN0Index) / 10); Eb1=sum(I_WaveformTx .* I_WaveformTx) / BitStreamLength; Eb2=sum(Q_WaveformTx .* Q_WaveformTx) / BitStreamLength; N0 = (Eb1+Eb2) / EbN0; sigma_N0=sqrt(N0); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%% Channel Transmit %%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % [I_WaveformRx, Q_WaveformRx] = AWGNChannel(I_WaveformTx, Q_WaveformTx, N0); I_WaveformRx = I_WaveformTx+ sigma_N0; Q_WaveformRx = Q_WaveformTx + sigma_N0; [I_SymbolRx, Q_SymbolRx] = Receivefilter(I_WaveformRx, Q_WaveformRx, ... hReceiveFilter, numSamplesPerSymbol); [BitStreamOneRx, BitStreamTwoRx] = DQPSKDecoder(I_SymbolRx, Q_SymbolRx); BitStreamRx = ParallelToStream(BitStreamOneRx, BitStreamTwoRx); Errors=sum( BitStream ~= BitStreamRx); BER(iters) = Errors/BitStreamLength; end AvBER( EbN0Index ) = sum(BER) / nIters ; end semilogy(LogEbN0, AvBER, '*'); grid on xlabel('Eb/No(dB)'); ylabel('Pe');