www.gusucode.com > wlan 源码程序 matlab案例代码 > wlan/EstimateSISOChannelUsingLLTFandSmoothingFilterExample.m
%% Estimate SISO Channel Using L-LTF and Smoothing Filter %% % Create a VHT format configuration object. Generate a time-domain waveform % for an 802.11ac VHT packet. vht = wlanVHTConfig; txWaveform = wlanWaveformGenerator([1;0;0;1],vht); %% % Multiply the transmitted VHT signal by 0.2 - 0.6i and pass it through an % AWGN channel having a 10 dB SNR. rxWaveform = awgn(txWaveform*complex(0.2,-0.6),10); %% % Extract the L-LTF from the received waveform. Demodulate the L-LTF. idxLLTF = wlanFieldIndices(vht, 'L-LTF'); lltfDemodSig = wlanLLTFDemodulate(rxWaveform(idxLLTF(1):idxLLTF(2),:),vht); %% % Use the demodulated L-LTF signal to generate the channel estimate. est = wlanLLTFChannelEstimate(lltfDemodSig,vht); %% % Plot the channel estimate. scatterplot(est) grid %% % The channel estimate is noisy, which may lead to inaccurate data % recovery. %% % Estimate the channel again with the filter span set to 11. est = wlanLLTFChannelEstimate(lltfDemodSig,vht,11); scatterplot(est) grid %% % The filtering provides a better channel estimate.