www.gusucode.com > wlan 源码程序 matlab案例代码 > wlan/EstimateMIMOChannelUsingVHTLTFExample.m

    %% Estimate MIMO Channel Using VHT-LTF
% Estimate and display the channel coefficients of a 4x2 MIMO channel using
% the VHT-LTF.

%%
% Create a VHT format configuration object for a channel having four
% spatial streams and four transmit antennas. Transmit a complete VHT
% waveform.
cfg = wlanVHTConfig('NumTransmitAntennas',4, ...
    'NumSpaceTimeStreams',4,'MCS',5);
txWaveform = wlanWaveformGenerator([1;0;0;1;1;0],cfg);

%%
% Set the sampling rate, and then pass the transmitted waveform through a
% 4x2 TGac channel.
fs = 80e6;
tgacChan = wlanTGacChannel('SampleRate',fs, ...
    'NumTransmitAntennas',4,'NumReceiveAntennas',2);
rxWaveform = tgacChan(txWaveform);

%%
% Determine the VHT-LTF field indices and demodulate the VHT-LTF from the
% received waveform.
indVHTLTF = wlanFieldIndices(cfg,'VHT-LTF');
ltfDemodSig = wlanVHTLTFDemodulate(rxWaveform(indVHTLTF(1):indVHTLTF(2),:), cfg);


%%
% Generate the channel estimate by using the demodulated VHT-LTF signal.
% Specify a smoothing filter span of five subcarriers.
est = wlanVHTLTFChannelEstimate(ltfDemodSig,cfg,5);
%%
% Plot the magnitude response of the first space-time stream for both
% receive antennas. Due to the random nature of the fading channel, your
% results may vary.
plot(abs(est(:,1,1)))
hold on
plot(abs(est(:,1,2)))
xlabel('Subcarrier')
ylabel('Magnitude')
legend('Rx Antenna 1','Rx Antenna 2')