WirelessNetworkingTechnologies/lab_4/link_level_measurements.md

This PDF will be a bit more 'well defined'

Reproducibility

Reproducibility factor	Task 1 value	Task 2 value	Task 3 value	Task 4.1 value	Task 4.2 value
MATLAB Version	26.1.0.3251617 (R2026a) Update 2	-	-	-	-
5G Toolbox Version	26.1	-	-	-	-
WLAN Toolbox Version	26.1	-	-	-	-
Communications Toolbox Version	26.1	-	-	-	-
Parallel Computing Toolbox Version	26.1	-	-	-	-
Random stream	mt19937ar with seed	-	-	-	-
Random seed	666	-	-	-	-
SNR vector	0:1:40 dB	-	-	-	-
Packet budget	1024 packets per SNR point	-	-	-	-
maxNumErrors	50	-	-	-	-
NTN profile	NTN-TDL-C	-	-	-	-
Carrier frequency	2.4 GHz	-	Task 3.2: [1 2.4 5 5.8 6 12 24 60] GHz	-	-
LEO altitude	600 km	-	-	-	-
Elevation sequence	10° to 90° to 10° over the packet sequence	-	-	-	-
Mean elevation angle	50°	-	-	-	-
Mean slant range	906.32 km	-	-	-	-
Mean satellite Doppler shift	32.73 kHz	-	changes with carrier frequency	-	-
Normalized CFO	0.419	-	changes with carrier frequency	-	-
Channel bandwidth	20 MHz	-	-	-	[20 40 80 160 320] MHz
MCS	2	-	-	[0 2 4 8 10 12 13]	3
APEP length	1000 B	[250 1000 4000 8000 12000] B	Task 3.1: [250 1000 4000 8000 12000] B; Task 3.2: 8000 B	-	-
TX/RX antennas	1-by-1 SISO	-	-	-	-
Pilot tracking	disabled	-	enabled	-	-
Parallelization	parfor over SNR points	-	-	-	-

Task1

1.1

See code lab_4.m, create_baseline_configuration.m and simulateTransmission.m.

1.2

The plot shows the packet error rate significantly decreasing as the signal to noise ration increases. This behavior can be observed when the snr reaches a value of 25, at that simulation point the signal significantly overweights the noise and the PER also significantly decreases in an negative exponential manner. At link level, PER is the fraction of transmitted PHY-layer packets that are not received correctly for a given channel model and SNR.

1.3

For the baseline configuration with f_c = 2.4GHz, LEO altitude 600km, orbital shifted elevation angle (Elevation sequence: 10° to 90° to 10° over the packet sequence, mean: 50°), and static receiver. The mean slant range is 906.32km, the computed mean satellite Doppler shift is approximately 32.73kHz. With the IEEE 802.11be subcarrier spacing of 78.125kHz, this corresponds to a normalized CFO of \epsilon \approx 0.419. Therefore, the Doppler shift is below one subcarrier spacing but still represents 41.9% of the OFDM subcarrier spacing.

1.4

CFR Magnitude single representative Packet:

The CFR magnitude of the representative packet is relatively flat over the active subcarriers. Only moderate variations are visible, without deep frequency-selective fades. Therefore, for the baseline 20 MHz NTN-TDL-C configuration, the channel appears mostly frequency-flat to mildly frequency-selective.

Complete CFR Magnitude over all representative Packets by first MCS:

The complete CFR collection is included as a consistency check. The collected packet CFRs show similar magnitude variations over the active subcarriers, indicating that the selected representative packet is typical for this baseline run. No strong deep fades are visible across most packets, so the 20 MHz NTN-TDL-C baseline appears mostly frequency-flat to mildly frequency-selective.