Made some progress, per snr sweep is plotted now, the satellites orbital shift is used in calculated now, code is prepared for more than one mcs value

lab_4/create_baseline_configuration.m

@@ -3,7 +3,6 @@ function [cfgEHT, simParameters, channel, chInfo, maxChDelay, satelliteDopplerSh
                                      include_free_space_pathloss, ...
                                      delay_model, ...
                                      carrier_frequency, ...
-                                     elevation_angle, ...
                                      mobile_speed, ...
                                      mobile_altitude, ...
                                      satellite_altitude, ...
@@ -11,8 +10,7 @@ function [cfgEHT, simParameters, channel, chInfo, maxChDelay, satelliteDopplerSh
                                      seed, ...
                                      tx_antenna_count, ...
                                      rx_antenna_count, ...
-                                     apep, ...
+                                     apep)
-                                     mcs)
 
     switch bandwidth_mhz
         case 20
@@ -33,13 +31,13 @@ function [cfgEHT, simParameters, channel, chInfo, maxChDelay, satelliteDopplerSh
     cfgEHT.User{1}.APEPLength = apep;
     cfgEHT.NumTransmitAntennas = tx_antenna_count;
     cfgEHT.User{1}.NumSpaceTimeStreams = 1;
-    cfgEHT.User{1}.MCS = mcs;
+    cfgEHT.User{1}.MCS = 0; % default to sweep later
     fs = wlanSampleRate(chanBW);
 
     simParameters.IncludeFreeSpacePathLoss = include_free_space_pathloss;
     simParameters.DelayModel = delay_model;
     simParameters.CarrierFrequency = carrier_frequency;
-    simParameters.ElevationAngle = elevation_angle;
+    simParameters.ElevationAngle = 0; % default to sweep later
     simParameters.MobileSpeed = mobile_speed;
     simParameters.MobileAltitude = mobile_altitude;
     simParameters.SatelliteAltitude = satellite_altitude;

lab_4/lab_4.m

@@ -2,12 +2,24 @@ carrier_frequency = 2.4e9;
 wifi_be_subcarrier_spacing = 78.125e3;
 leo_altitude = 600e3;
 bandwidth = 20; 
-mcs = 2;
+mcs_values = [2];
 apep = 1000;
 tx_antenna_count = 1;
 rx_antenna_count = 1;
 
-elevation_angle = 50;
+snrs = (0:1:40);
+packets_per_snr = 250;
+maxNumErrors = 50;
+
+% elevation_angle = 50;
+elevationAngles = [ ...
+    linspace(10, 90, ceil(packets_per_snr / 2)), ...
+    linspace(90, 10, floor(packets_per_snr / 2)) ...
+];
+
+meanElevationAngle = mean(elevationAngles);
+slantRanges = arrayfun(@(el) slantRangeCircularOrbit(el, leo_altitude, 0), elevationAngles);
+dopplerShifts = arrayfun(@(el) dopplerShiftCircularOrbit(el, leo_altitude, 0, carrier_frequency), elevationAngles);
 
 random_stream = "mt19937ar with seed";
 seed = 666;
@@ -16,28 +28,46 @@ ntn_tdl_delay_profiles = ["A" "B" "C" "D"];
 
 [cfgEHT, simParameters, channel, chInfo, maxChDelay, satelliteDopplerShift, chanBW] = ...
     create_baseline_configuration(ntn_tdl_delay_profiles(3), bandwidth, false, "None", ...
-                       carrier_frequency, elevation_angle, 0, ...
+                       carrier_frequency, 0, ...
                        0, leo_altitude, random_stream, ...
                        seed, tx_antenna_count, ...
-                       rx_antenna_count, apep, mcs);
+                       rx_antenna_count, apep);
 
-normalized_cfo = satelliteDopplerShift / wifi_be_subcarrier_spacing;
+meanSlantRange = mean(slantRanges);
+meanSatelliteDopplerShift = mean(dopplerShifts);
 
-disp("Channel Info: ")
+meanNormalizedCFO = meanSatelliteDopplerShift / wifi_be_subcarrier_spacing;
-disp(chInfo)
-disp("Satellite Doppler Shift: " + satelliteDopplerShift)
-disp("Normalized CFO: " + normalized_cfo)
 
+disp("Mean Elevation Angle: " + meanElevationAngle + "°")
+disp("Mean Slant Range: " + meanSlantRange + "m")
+disp("Mean Satellite Doppler Shift: " + meanSatelliteDopplerShift + "Hz")
+disp("Normalized CFO: " + meanNormalizedCFO)
 
-snrs = (0:1:40);
+errorRates = zeros(numel(mcs_values), numel(snrs));
-packets_per_snr = 250;
+for imcs = 1 : numel(mcs_values)
-maxNumErrors = 10;
+    cfgEHT.User{1}.MCS = mcs_values(imcs);
-
+    parfor snr_idx = 1 : length(snrs)
-errorCounts = zeros(size(snrs));
+        local_channel = clone(channel)
-for snrIndex = 1:length(snrs)
+        [errorCount, packetCount] = simulateTransmission(cfgEHT, local_channel, maxChDelay, snrs(snr_idx), packets_per_snr, maxNumErrors, simParameters, chanBW, snr_idx, elevationAngles);
-    errorCounts(snrIndex) = simulateTransmission(cfgEHT, channel, snrs(snrIndex), packets_per_snr, maxNumErrors, simParameters, chanBW, snrIndex);
+        
+        errorCounts(snr_idx) = errorCount;
+        packetCounts(snr_idx) = packetCount;
+        errorRates(imcs, snr_idx) = errorCount / packetCount;
+    end
 end
 
-errorRate = errorCounts / packets_per_snr;
+markers = 'ox*sd^v><ph+ox*sd^v><ph+';
-
+figure;
-disp("ErrorRatePerSNR: " + errorRate);
+for imcs = 1 : numel(mcs_values) 
+    semilogy(snrs, errorRates(imcs, :).',['-' markers(imcs)]);
+    hold on;
+end
+grid on;
+xlabel('SNR (dB)');
+ylabel('PER');
+% task 1
+dataStr = arrayfun(@(x)sprintf('MCS %d',x), 2, 'UniformOutput', false);
+% task 4
+% dataStr = arrayfun(@(x)'MCS Sweep Values: [0 2 4 8 10 12 13]', 'UniformOutput', false);
+legend(dataStr, 'Location', 'NorthEastOutside');
+title(['PER (EHT MU), ' num2str(cfgEHT.ChannelBandwidth) ', NTN-TDL-C, ' num2str(tx_antenna_count) '-by-' num2str(rx_antenna_count)]);

lab_4/link_level_measurements.md

@@ -1,4 +1,18 @@
 > This PDF will be a bit more 'well defined'
 
+## Reproducability
+|reproducability factor | value |
+|:---|---:|
+| MATLAB Version | 26.1.0.3251617 (R2026a) Update 2 |
+| Toolboxes/Version | 5G/26.1 |
+|| WLAN/26.1 | 
+|| Communication/26.1 |
+|| Parallel Computing/26.1 |
+| random seed | 666 |
+| SNR vector | 0:1:40dB |
+| packet budget | 250 |
+| maxNumErrors | 50 |
+>
+
 ## Task1
 For the baseline configuration with f_c = 2.4GHz, LEO altitude 600km, elevation angle 50° (like example), and static receiver, the computed satellite Doppler shift is approximately 35.56kHz. With the IEEE 802.11be subcarrier spacing of 78.125kHz, this corresponds to a normalized CFO of \epsilon \approx 0.455. Therefore, the Doppler shift is below one subcarrier spacing but still represents a significant fraction of the OFDM subcarrier spacing.

lab_4/simulateTransmission.m

@@ -1,5 +1,6 @@
-function numPacketErrors = simulateTransmission(cfgEHT, channel, snr, packets, maxNumErrors, simParameters, chanBW, substreamIndex)
+function [numPacketErrors, numPacketsSimulated ]= simulateTransmission(cfgEHT, channel, maxChDelay, snr, maxNumPackets, maxNumErrors, simParameters, chanBW, substreamIndex, elevationAngles)
     numPacketErrors = 0;
+    numPacketsSimulated = 0;
 
     ofdmInfo = wlanEHTOFDMInfo('EHT-Data', cfgEHT);
     ind = wlanFieldIndices(cfgEHT);
@@ -14,15 +15,16 @@ function numPacketErrors = simulateTransmission(cfgEHT, channel, snr, packets, m
 
     snrVal = convertSNR(snr, "snrsc", "snr", FFTLength=ofdmInfo.FFTLength, NumActiveSubcarriers=ofdmInfo.NumTones);
 
-    for packetIdx = 1:packets
+    while numPacketErrors < maxNumErrors && numPacketsSimulated < maxNumPackets
-        if numPacketErrors >= maxNumErrors
+        numPacketsSimulated = numPacketsSimulated + 1;
-            break;
+
-        end
+        packetElevationAngle = elevationAngles(numPacketsSimulated);
+        channel.SatelliteDopplerShift = dopplerShiftCircularOrbit(packetElevationAngle, simParameters.SatelliteAltitude, simParameters.MobileAltitude, simParameters.CarrierFrequency);
 
         txPSDU = randi([0 1], psduLength(cfgEHT) * 8, 1);
         tx = wlanWaveformGenerator(txPSDU, cfgEHT);
 
-        txPad = [tx; zeros(50, cfgEHT.NumTransmitAntennas)];
+        txPad = [tx; zeros(maxChDelay, cfgEHT.NumTransmitAntennas)];
 
         reset(channel);
         rx = awgn(channel(txPad), snrVal);
@@ -37,12 +39,12 @@ function numPacketErrors = simulateTransmission(cfgEHT, channel, snr, packets, m
         coarseFrequencyOffset = wlanCoarseCFOEstimate(lstf, chanBW);
         rx = frequencyOffset(rx, simParameters.SampleRate, -coarseFrequencyOffset);
 
-        nonhtfields = rx(coarsePacketOffset + (ind.LSTF(1) : ind.LSTF(2)), :);
+        nonhtfields = rx(coarsePacketOffset + (ind.LSTF(1) : ind.LSIG(2)), :);
         finePacketOffset = wlanSymbolTimingEstimate(nonhtfields, chanBW);
 
         packetOffset = coarsePacketOffset + finePacketOffset;
 
-        if packetOffset > 50
+        if packetOffset > maxChDelay
             numPacketErrors = numPacketErrors + 1;
             continue;
         end