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) 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
