On Fri, May 23, 2008 at 06:54:16AM -0400, Charles Swiger wrote: > On Thu, 2008-05-22 at 22:35 -0700, Eric Blossom wrote: > > On Thu, May 22, 2008 at 10:53:12PM -0400, Achilleas Anastasopoulos wrote: > > > > > > So the signal u(t) needs to be sampled at 6 Complex-Msps, which is what > > > you > > > do (sampling it at 6.4 Complex-Msps, or as Eric wants at 8 complex-Msps). > > > > > > > I'm worried about the roll off at the edges of the passband at 6.4 MS/s. > > We're only flat to about 70% of Fs, which is 4.5 MHz at 6.4 MS/s. > > If it can be made to work well at 6.4 MS/s, that's great. > > > > Your right, it would probably work better at 8Msps - however, with a > decent signal it *does* work at 6.4Msps. It's an engineering trade-off, > you want it fast or good? For now I want to squeeze out all the fat just > to get it to work at all in real time, then when we get enough > effeciency / cpu horsepower make it work well for marginal signals.
For my part, I want it good, then fast. Marginal signals are all you'll ever get with an indoor antenna ;) There's plenty of stuff we can do to make it fast. We haven't even begun to scratch the surface. We only need to carry the 8 MS/s through the first couple of blocks, then we'll be running at the 10.76 symbol rate. Eric _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
