Hi I was also looking around the OFDM Modulation recently. Found this nice project here: http://people.csail.mit.edu/szym/rawofdm/README.html where ofdm mod and channel est are done separately. I didn't had the time to follow ths more...perhaps it helps.
best, friederike On 01/20/2012 02:38 PM, vanITA1082 wrote: > > Did you solve it? > > I am trying to add FEC in the OFDM chain but I didn't figure out how to do > this, yet. > > Any advice or do you know if someone did it and the code is public? > > Thanks > > Veljko Pejovic wrote: >> >> Hi, >> >> I tried to use trellis_encoder from trellis package to perform >> convolution coding before sending the message to the OFDM modulator. >> However, ofdm_mod has zero input signature, and relies on send_pkt() >> which calls ofdm_packet_utils.make_packet() and then puts the message >> in the queue at gr.ofdm_mapper_bcv. Since the chain basically starts >> with ofdm_mod I don't see the way to connect the trellis_encoder >> before the signal is already modulated. In ftw80211 project they >> modify ofdm_packet_utils and write their own convolution coding >> method, I could do the same, but then I would miss all the benefits of >> this nice trellis package. >> >> Interestingly, the other modulation blocks such as dbpsk or d8psk have >> different input signatures, and I would put the trellis_encoder >> between the gr.message_source and modulator in pkt.py. Is there a way >> to seamlessly introduce trellis_encoder in the flow graph with an OFDM >> modulator? Am I missing something here? >> >> >> Thanks, >> >> >> Veljko >> >> >> _______________________________________________ >> Discuss-gnuradio mailing list >> Discuss-gnuradio@gnu.org >> http://lists.gnu.org/mailman/listinfo/discuss-gnuradio >> >> > _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
