>>> Hum... I'm glad to hear that, although I thought that the pi- phase >>> ambiguity of Costas- loops made them unsuitable for QPSK- >>> constellations... But I guess there is something I'm missing in the code >>> then? >>> >> You aren't missing anything, you just need to account for the possible >> rotation. >> >> The easy way to do this is with differential decoding, because the >> instantaneous phase is irrelevant. >> >> The harder-but-still-easy was is to transmit some know sequence at the >> beginning to determine the phase offset and adjust your decoding >> accordingly. >> >> Jason >> > > > Yes, what Jason said. > > I think of synchronization as making sure the constellation is > aligned. The actual bit representations are the next step. Since we > put a 64-bit access code on the front of every packet, it should be > easy to add logic in the sink to determine what the rotation is, but > we haven't done anything about that. > > Tom > Maybe I should have taken a few minutes to think about what was really going on, before I started to write interleaved pilot- symbols in the data- stream, and correcting the data on them at the rx- side then... Anyway I got some more experience thinking in "gnuradio c++", and now a new view upon things ;]
//Mattias _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
