On Oct 13, 2010, at 12:32 AM, David McClain <[email protected]> wrote:
> Hello John, > >> Well, not entirely -- it's common enough to see FFT applications that >> compute frequency readings at sub-bin precision by tracking atan(Q,I) across >> multiple time records. That is a well-defined thing to do, since the > > > Yes, indeed, I am familiar with that technique from my SIGINT days... > however, what you are really doing is extending the sampling period by > looking at multiple scans. And so that isn't really any different at its base > than just taking a longer period FFT. > > The only way I have ever seen super-resolution is when you do AR > deconvolution, bearing in mind that wherever there are instrumental induced > zeros in the spectrum, you will get nonsense values in the result. AR, aka > maximum-entropy, attempts to produce a minimum norm estimate, akin to that > from SVD analysis. > That's but one way. There's also music and esprit as well of a host of other similar methods. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
