Re: FFTs of FFTs

dbd wrote:

...

If you are really calculating the magnitude spectrum of the first fft,
as you said, the DC term of the magnitude spectrum of the first fft is
the square root of the square of the sum of the inputs to the first
fft. ...

Not so. Depending on scaling, the DC term is the sum of the inputs, their arithmetic mean, or something between. There is no squaring, rooting, or other non-linear operation involved.

Jerry
--
Engineering is the art of making what you want from things you can get.
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