seems finished

lab_3/task4.m

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+% disp("Results Task 4:" + newline)
+
+saveToFile = true;
+
+ssid = "wlan fahren wir noch";
+beaconInterval = 100;
+band = 2.4;
+channel = 1;
+
+frameBodyConfig = wlanMACManagementConfig(BeaconInterval=beaconInterval, SSID=ssid);
+
+dsElementID = 3;
+dsInformation = dec2hex(channel, 2);
+frameBodyConfig = frameBodyConfig.addIE(dsElementID, dsInformation);
+
+beaconFrameConfig = wlanMACFrameConfig(FrameType="Beacon", ManagementConfig=frameBodyConfig, FromDS=false);
+
+[mpduBits, mpduLength] = wlanMACFrame(beaconFrameConfig, OutputFormat="bits");
+
+fc = wlanChannelFrequency(channel, band);
+
+cfgNonHT = wlanNonHTConfig(PSDULength=mpduLength);
+
+osf = 1;
+tbtt = 1e-3;
+txWaveform = wlanWaveformGenerator(mpduBits, cfgNonHT, OversamplingFactor=osf, NumPackets=5, IdleTime=tbtt);
+
+Rs = wlanSampleRate(cfgNonHT,OversamplingFactor=osf);
+
+if saveToFile
+    iq = txWaveform;
+    % store to pass filepath to analyzeTrace
+    save("traces/wlan_fahren_wir_noch_beacons.mat", "iq");
+end
+
+% parameters from task1.m
+generatedTrace = analyzeTrace("traces/wlan_fahren_wir_noch_beacons.mat", channel, window, overlap, fft_precision, Rs);
+
+generated_p_dB_min = prctile(generatedTrace.P_dB(:), 1);
+generated_p_dB_max = prctile(generatedTrace.P_dB(:), 99.9);
+
+plotSpectrogram(generatedTrace, 5, generated_p_dB_min, generated_p_dB_max);
+
+%{
+The first thing I noticed is that most of the spectrogram is shown in the
+lowest color range. This is expected, because the generated waveform is a
+synthetic signal and does not include receiver noise, interference, other
+WiFi transmissions, or non-WiFi signals.
+
+The only relevant signal components are the generated beacon frames. Between
+the beacons, the waveform contains idle time, so the power is close to zero
+and therefore appears at the lowest dB level in the spectrogram.
+
+Over time, the spectrum only changes when a beacon frame is transmitted.
+During these short intervals, the OFDM signal occupies the 20 MHz channel.
+Between the beacon frames, there is no meaningful signal energy. Since the
+generation is done under ideal conditions, the repeated beacons look very
+similar and there are no random channel effects, noise floor variations, or
+additional transmissions as in the recorded SDR traces.
+
+For visualization, the idle time was reduced to 1 ms and NumPackets was set
+to 5, so that multiple beacon frames are visible close to each other in the
+spectrogram. This does not represent the normal beacon interval of 100 TU
+(about 102.4 ms), but makes the generated frames easier to compare visually.
+%}