On 30.04.2014 16:03, David Halls wrote:
It's just the built in basic FDE. Its not awesome, but works well enough at high SNR.
Hm, the FDE doesn't output soft info, so I'm stumped why you'd see anything other than clean constellation points in the first place.
Yes, when I send multiple packets, its only the last OFDM symbol of the last packet that is affected. I have tried suffixing FFT_len/4 (i.e. 16 = CP) lots of 0's in the TD at the transmitter, and this fixes the problem (low power noise instead of 0's also works). Could it be an analogue issue? It is always the last symbol, i.e. the end of the transmission, and it looks like the power might trail off from the attached picture? But it seems strange that it's exactly the last symbol? Could the pulse shaping performed in the cyclic prefixer have any effect?!
From your other email, it looks like it does... but you can't set the rolloff to the CP length, you need some space for multipath.
Martin _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
