I am trying to demodulate DBPSK with a baud rate of 100 symbol/sec and I have a sample rate of 250000 samples/sec. To obtain my sample rate of 100 symbol/sec I realise a decimation by 125 to obtain 20 samples/symbol. On my constellation I can see properly 2 points. But when I recover my data I don't find the same size of my payload that I transmit. I always have 1 bit that is not correct.
Do I demodulate correctly ?
I already try to use the block DPSK demod, MPSK receiver, and PSK demod but for me the FLL band edge doesn't work better than costa loop. And after some test, clock recovery seems to work more better than polyphase clock recovery. I have also try to decimate more in order to obtain 2 samples/symbol but I still have the same problem.
Thank you for your help.
Sincerely,
Treza