Goertzel algorithm on CH32v203 RISC-V
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The receiver with the Goertzel algorithm is about 2/3 through.
What we call Goertzel mode on the P2 does not actually use Goertzel's algorithm. https://en.wikipedia.org/wiki/Goertzel_algorithm It's clever algorithm. It can also be used in reverse to efficiently generate a sine wave.
He mentions this trick too: https://dspguru.com/dsp/tricks/complex-downconverters-at-fs-over-4/
Comments
Thanks, James. That is pretty neat. That's the kind of stuff we like to think about.