Best way to carry on 2-input architecture?

Niels Möller nisse at
Fri Aug 22 17:25:09 UTC 2014

nisse at (Niels Möller) writes:

> For concreteness, say we attempt to use a size 16 FFT, over the
> cofficient ring 2^{12}+1 (it's some years since I last looked carefully
> at FFT-based multiply, but I hope those parameters make sense. The FFT
> inputs are 4 bits, but grow to 12 in the output convolution).

Sorry, that won't work, one has to use the coefficient ring Z/(2^{16}
+1) to get the right roots of unity. I think.

Anyway, I have a better understanding of the advantages of separate
mullo and mulhi now. Thanks a lot.


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