[Discuss-gnuradio] OFDM with continuous pilots but bursty data
Hi Alex, you may want to take a look at the OOT module gr-cdma ( https://github.com/anastas/gr-cdma). This system implements a two-channel system with one of the orthogonal channels being continuously transmitting pilots, while the other carries data (in a synchronous/asynchronous way). The Rx is always listening to the pilot channel and is continuously adjusting frequency/timing. Achilleas ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] OFDM with continuous pilots but bursty data
Hi Alex - The default OFDM Rx is fully asynchronous: It tries to detect the packet preamble on a packet by packet basis only, without using any knowledge of historical successful packet detection. I don't think GR provides a synchronous receiver, and I don't know of one in any GR out of tree (OOT) module ... but I don't know everything so maybe there is one & if so hopefully others will chime in to tell us! Hope this is useful! - MLD On Tue, Aug 13, 2019, at 1:04 PM, Alex Roberts wrote: > I'm playing around with an OFDM transmit/receive chain. I've noticed that if > I get underruns at a high enough rate, it becomes a bursty system and the > receiver is unable to lock in and no longer demodulates the symbols. > > Would it be possible to generate continuous pilot tones or send OFDM frames > with just preambles and padded data such that even if the source data stream > underruns, the output is continous rather than bursty so that the receiver > can keep lock with time and frequency offests? > > -Alex > ___ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] OFDM with continuous pilots but bursty data
I'm playing around with an OFDM transmit/receive chain. I've noticed that if I get underruns at a high enough rate, it becomes a bursty system and the receiver is unable to lock in and no longer demodulates the symbols. Would it be possible to generate continuous pilot tones or send OFDM frames with just preambles and padded data such that even if the source data stream underruns, the output is continous rather than bursty so that the receiver can keep lock with time and frequency offests? -Alex ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio