I'm looking at fine tuning the frequency to a known FM broadcast automatically. (from complex signal) My beginner's idea is to either:
- lowpass filter to get ~2x the bandwidth visible
- do the frequency demod
- get a moving average
- apply frequency correction until the average is ~0
or do the same thing, but after demodulation apply a bandpass filter to the pilot frequency.
Either way seems to work ok - but should one of them be significantly better than the other? I guess the pilot signal is more stable in this case.
Is there any better solution for fine-tuning that I'm not aware of? (My knowledge here is limited)
Unless I misunderstood the description, this would be similar behaviour to what Foster–Seeley discriminator is aiming for, right?