Hi all, I did some investigations regarding the zero output problem: First of all I installed gnuradio 0.9 on an old Red Hat 9 installation and made tests with the files from http://comsec.com/data/README. As the 0.9 ATSC DTV decoder works fine, I took the intermediate save files (*.rxout, can be obtained when using the log function) and used them as input for the version 3.x ATSC decoder. It turned out that everything works fine if I use the 0.9 output after the bit timing loop (bt_*.rxout) as input for the 3.x frame sync block. Further, if I use the 0.9 fpll output as input for the 3.x bit timing loop nothing happens (zero output). So I guess the problem can be isolated to the bit timing loop. I still do not fully understand the code, so I hope someone can help me to further isolate the problem. If we can fix this we would finally have a working gnuradio ATSC receiver again! Regards Klaus
-----Ursprüngliche Nachricht----- Von: [email protected] [mailto:[email protected]] Im Auftrag von Klaus Hueske Gesendet: Donnerstag, 24. Juni 2010 09:52 An: [email protected] Betreff: Re: [Discuss-gnuradio] ATSC decoding Hi Stephen, Did you make progress with this zero byte output problem? Anyway, I'm wondering if the ATSC receiver implementation will work at all with the current version of Gnuradio. It looks like parts of the original ATSC implementation that was working with Gnuradio 0.9 have been adapted to be used in Gnuradio 2.0, but now we have 3.2.2. Anyone here who can verify that the provided code can decode ATSC signals? Thanks Klaus --- On Mon, Apr 19, 2010 at 8:12 PM, Stephen Branch <addr...@hidden> wrote: >Hello everyone, > >I am part of Auburn University's Software Defined Radio Senior Design >team, > >Software being used: >Ubuntu v.9.10 on xfs partition >GNURadio v.3.3 (git) >Xine > >Available hardware: USRP1, USRP2, WBX daughterboard, TVRX daughterboard > >We followed the instructions in ./gnuradio/gr-atsc/src/python/README to >no >success. > >Using the FFT we found 507.25M to have a strong signal. According to >http://en.wikipedia.org/wiki/North_American_broadcast_television_freque ncie s#UHF_band > this is channel 20. >And according to >http://www.fcc.gov/fcc-bin/tvq?state=AL&call=&arn=&city=&chan=14&cha2=6 9&se rv=&type=0&facid=&list=2&dist=&dlat2=&mlat2=&slat2=&dlon2=&mlon2=&slon2= &siz e=9 > this is WCOV from Montgomery, Alabama. >So we do have the correct video carrier frequency, which I assume is >the >frequency we want to record and decode into a video. > >Question #1) Is the video carrier the one that carriers the video, or >would it >be the ATSC carrier? > >We then used: >./usrp_rx_cfile.py -s -d 10 -g 20 -f 507.25e6 atsc_data_6-4m_complex >./interp_short.py atsc_data_6-4m_complex ./xlate.py >./fpll.py >./btl-fsd.py >./viterbi-out.py test.mpeg > >Problems: >/tmp/atsc_pipe_5 never fills with data. >The output file, 'test.mpeg' is empty. > >Question #2) What do we need to fix to get /tmp/atsc_pipe_5 to fill. >Question #3) What do we need to fix to get temp.mpeg to fill. > >Thank you, >Bobby Black & Stephen Branch >addr...@hidden (please do not blank out this email) >black85 @ auburn . edu > >Bobby Black >Auburn University >addr...@hidden >(334) 804-4826 _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
