To Bill (and Joe),

It just occurred to me that I could multicast my receiver output to you
in the frequency domain. UDP already provides the necessary framing. We
just define that as a new RTP "codec type".

I use fast convolution with overlap-and-save for filtering, so as long
as I tell you the parameters (i.e, FFT block size and the overlap
amount) I could just give you the frequency domain signal before I'd
ordinarily perform the IFFT. This would save me the IFFT (though I'd
probably do it anyway just so I could listen). With the right blocksize,
it might also save you an FFT.

To be honest, at that point there wouldn't be much left for my receiver
to do. Or you could just read my raw SDR I/Q streams directly...

We could also reduce the bandwidth by just truncating the frequency
information, though I'd have to apply a low pass decimation filter to
avoid aliasing. I use Kaiser windowing for pretty much everything; I
really like its tuning knob to trade transition sharpness against
stopband sidelobes. (I also worked with Jim Kaiser at Bellcore way back
in the 1980s.)


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