--- Mathieu Bouchard matju@artengine.ca wrote:
On Tue, 29 Nov 2005, Stefan Turner wrote:
I think the standard way of convolution - or at
least the one I use -
which gives ok results, is to have one 'carrier'
signal, which is
filtered by the 'modulator' signal. (I think
that's what they're
called.) Basically, first get the magnitude of the
modulator:
sqrt(real^2 + imag^2). Then: output real = carrier real * modulator magnitude output imag = carrier imag * modulator magnitude
This is not a plain convolution by the modulator signal, though it's close. It's a convolution by the phase-removed modulator signal, because all phase information is removed. A general convolution allows for phase shifts.
<snip> > A general convolution uses complex multiplications, > one of which requires > four real multiplications in cartesian repr, one > real multiplication in > polar repr, and no multiplication in log repr.
Yes, thanks for pointing this out. Apologies for this. I have since posted the correct equations, for cartesian.
Stefan Turner
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