i think that this is nearly the beginning of task 1

2026-06-03 19:46:31 +02:00
parent 4395bbe0b1
commit 78b271247c
7 changed files with 200 additions and 0 deletions
@@ -0,0 +1,72 @@
+function numPacketErrors = simulateTransmission(cfgEHT, channel, snr, packets, maxNumErrors, simParameters, chanBW, substreamIndex)
+    numPacketErrors = 0;
+
+    ofdmInfo = wlanEHTOFDMInfo('EHT-Data', cfgEHT);
+    ind = wlanFieldIndices(cfgEHT);
+
+    if nargin < 8
+        substreamIndex = 1;
+    end
+
+    stream = RandStream('combRecursive', Seed=simParameters.Seed);
+    stream.Substream = substreamIndex;
+    RandStream.setGlobalStream(stream);
+
+    snrVal = convertSNR(snr, "snrsc", "snr", FFTLength=ofdmInfo.FFTLength, NumActiveSubcarriers=ofdmInfo.NumTones);
+
+    for packetIdx = 1:packets
+        if numPacketErrors >= maxNumErrors
+            break;
+        end
+
+        txPSDU = randi([0 1], psduLength(cfgEHT) * 8, 1);
+        tx = wlanWaveformGenerator(txPSDU, cfgEHT);
+
+        txPad = [tx; zeros(50, cfgEHT.NumTransmitAntennas)];
+
+        reset(channel);
+        rx = awgn(channel(txPad), snrVal);
+
+        coarsePacketOffset = wlanPacketDetect(rx, chanBW);
+        if isempty(coarsePacketOffset)
+            numPacketErrors = numPacketErrors + 1;
+            continue;
+        end
+
+        lstf = rx(coarsePacketOffset + (ind.LSTF(1) : ind.LSTF(2)), :);
+        coarseFrequencyOffset = wlanCoarseCFOEstimate(lstf, chanBW);
+        rx = frequencyOffset(rx, simParameters.SampleRate, -coarseFrequencyOffset);
+
+        nonhtfields = rx(coarsePacketOffset + (ind.LSTF(1) : ind.LSTF(2)), :);
+        finePacketOffset = wlanSymbolTimingEstimate(nonhtfields, chanBW);
+
+        packetOffset = coarsePacketOffset + finePacketOffset;
+
+        if packetOffset > 50
+            numPacketErrors = numPacketErrors + 1;
+            continue;
+        end
+
+        rxLLTF = rx(packetOffset + (ind.LLTF(1) : ind.LLTF(2)), :);
+        fineFrequencyOffset = wlanFineCFOEstimate(rxLLTF, chanBW);
+        rx = frequencyOffset(rx, simParameters.SampleRate, -fineFrequencyOffset);
+
+        rxHELTF = rx(packetOffset + (ind.EHTLTF(1) : ind.EHTLTF(2)), :);
+        heltfDemod = wlanEHTDemodulate(rxHELTF, "EHT-LTF", cfgEHT);
+        [chanEstimate, pilotEstimate] = wlanEHTLTFChannelEstimate(heltfDemod, cfgEHT);
+
+        rxData = rx(packetOffset + (ind.EHTData(1) : ind.EHTData(2)), :);
+        demodSym = wlanEHTDemodulate(rxData, "EHT-Data", cfgEHT);
+
+        nVarEst = wlanEHTDataNoiseEstimate(demodSym(ofdmInfo.PilotIndices, :, :),pilotEstimate, cfgEHT);
+
+        demodDataSym = demodSym(ofdmInfo.DataIndices, :, :);
+        chanEstimateData = chanEstimate(ofdmInfo.DataIndices, :, :);
+
+        [eqSym, csi] = wlanEHTEqualize(demodDataSym, chanEstimateData, nVarEst, cfgEHT, 'EHT-Data');
+
+        rxPSDU = wlanEHTDataBitRecover(eqSym, nVarEst, csi, cfgEHT);
+
+        numPacketErrors = numPacketErrors + any(biterr(txPSDU, rxPSDU));
+    end
+end