Re: fourier anlysis of square wave...

suren wrote:
Hello Folks,
I convert a sine wave to a square wave using a zero crossing detector
function, i.e output = 1 if input >0 else output =-1.
If I plot the FFT of the resulting square wave, I see lots of tones
that are not harmonics of the fundamental frequency of the sine wave.
Can anyone explain this.

The non-harmonic tones are aliases. Do you understand about aliasing in sampled signals?

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

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