Vincenzo, I did some experiments with DAB which is, (due to differential modulation), simpler than DVB. On the PHY level I managed to get "almost" (about 60%) real-time performance on my P4 with GNU Radio and prerecorded samples.
This was only PHY (even without channel coding!), and the synchronization algorithm used was pretty shaky. Channel coding eats up a lot of resources as well, look at the throughput figures for gr-trellis. DAB has a bandwidth of 1,5 MHz, DVB more than 5 MHz. All in all considered, my guess is that 5-8 years from now it might be possible to do these kind of bandwidths on a general purpose processor. But this is just my unjustified guess. :-) When starting to work on DVB, you'll have to write a transmitter chain and a receiver separately, to you can test both. Just look at the GNU Radio examples. I would suggest to limit your final thesis to the PHY layer first - OFDM synchronization by itself is a real challenge. What I noticed is that, due to the way transmission protocols are designed, there is not "one solutions fits all" approach. You would have to tailor available OFDM code to the specific needs of DVB (DAB). A good way to start might be the new GNU Radio OFDM code available from trunk. A good way to "get a feeling" for real data might be to look at it in Matlab or Octave. You could test signal processing algorithms in such an enviroment as well. Best regards, Jens > I am a telecommunication engineering student in italy at Pisa University > (Italy) at the moment, and it is quite likely that my final thesis (to be > started in about a year from now) will be a DVB-T transmitter. > > So I'm slowly approaching the subject, and starting to figure out some > preliminary choices and possibilities... > > My first questions then are : > > ..Do you think it is possible to reach real time, considering hardware > improvements since the video was recorded? > > ..How could I test a non real time transmitter? (I think I > understand not real time receiver but how did you test the > transmitter?) > > > Best Regards > -- > Vincenzo Pellegrini > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > http://lists.gnu.org/mailman/listinfo/discuss-gnuradio _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
