Why does the Multipath Rayleigh Fading Block produce inaccurate results in certain cases?
I tested the "Communications Blockset/Channels/Multipath Rayleigh Fading Block" with the following parameters:
Doppler frequency: 200 Sample time: 1e-5 Delay vector: 0 Gain vector: 0 Normalization: on Initial seed: 1234
The input was a real sine wave of 1000 Hz (transformed into a complex input with the "Real-Imag to Complex Block", the imaginary part was a constant zero).
The output was written to the workspace and the Simulation time was 5.3 seconds.
The FFT of the result showed a doppler bandwidth of 2*150 Hz.
Altering the Doppler frequency to 199 Hz showed the same value (2*150 Hz).
Altering the Doppler frequency to 201 Hz showed a Doppler bandwidth of 2*225 Hz.
A few Hz difference could be explained with the necessity of integer interpolation factors, however this difference is too great.
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