On 8/20/11 6:40 AM, Ronald G. Parsons wrote: > > With these two changes, although the Doppler correction may drift off, > it does so very smoothly, which I assume allows the decoding of the BPSK > data to be more accurate.
Yes, the closer you keep it the better it'll work. Errors of up to +/- 50 Hz are fairly negligible, but beyond that it starts to degrade. The demodulator searches +/- 200 Hz in 100 Hz steps around a nominal carrier frequency of 1500 Hz. I should probably have made it search a wider range but with that much mistuning the sidebands would start to be clipped off by the edges of a typical SSB filter. _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
