On Tue, Mar 21, 2006 at 05:22:04PM -0800, mao mao wrote: > Sounds good! > > I am still not convinced that USRP can handle ATSC > demodulation. Please tell me how are you gonna recover > the carrier with 16Ms data and 4MHz IF? If this > problem can be solved, the rest are pretty easy.
The USRP can sample, filter and decimate to 8MS/s complex across the USB. Per Nyquist, 8MS/s complex is sufficient to represent our 6 MHz bandwidth of interest. We just restructure the PLL to accept complex input data, use a complex NCO and then track the pilot as before. In fact, we may be able to use one of the gr_pll_* blocks in gnuradio-core/src/lib/general. > The reason why I want to buy a working mc4020/mt4937 > combo is that I want to play with REAL HDTV data. This > is way more exciting than playing with the test data. Yes. I want to work with real data too. However, there are lots of things that can go wrong when using real data. Antenna pointing, multipath, equalization, etc. That's why I like to start with a controlled environment and reproducible test cases for the entire tx and rx paths. Once those are working, I'm all for playing with real data. Otherwise, what's the point ;) > If you can recover the atsc carrier with USRP, I can > finish the rest of atsc code real quick OK. I'll move the stuff into gr-atsc tonight or tomorrow. I'll send you more info off-list to get you set up as a committer. Eric _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
