On Fri, May 22, 2009 at 09:42:00AM -0400, Tom Lutz wrote: > I was having a very difficult time trying to get a Costas Loop to work > yesterday for order=2. I discovered, by the end of the day, several > things: > > 1. Min and Max frequency are in Radians per Sample (the documentation > says 'normalized', but I wasn't sure whether it meant cycles/sample or > radians/sample)
Fixed in the .h file. Not yet committed. > 2. The loop likes a signal that lies on the unit circle (i.e. > magnitude=1). I was using unscaled data that ranged from -150 to > 150....not so good! I used Automatic Gain Control to fix this. > > I used a nominal value of 0.01 for alpha and alpha^2/4 for beta, but I > suppose you should tweak these by testing the response of the loop for > various stimuli. > > I think I'll update the documentation to make things more explicit. > > Cheers, > Tom _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
