When i interpret para 4 of ETSI TS 100 392-15 it looks like the channels
are spaced at 25Khz.
The default low_pass used in all of the demods is 25Khz.
But when i look in the FFT of the complex signal, the 25Khz specified in
the cutoff_freq of firdes.low_pass causes a passband of twice the width.
Isn't this way to much? Shouldnt the cutoff_freq be 12.5Khz, giving a
passband of 25Khz? (Or is there an intentional spectral overlap between
adjacent channels?)
If this is the cause, should we just change the parameter to filterwidth
or channelspacing and use a /2 in the cutoff parm?
Gr. Sim
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