fft of a non-linear operation.

[amriths04]

non linear fft

say if i have 2 signals m1(t) and m2(t) how do i analytically evaluate

FFT(signum (m1(t)-m2(t)) ) ?

NOTE:
signum(x) is defined as 1; if x>0;
as -1;if x<0.



Any theorems or references would be greatly appreciated.

 

[horzcat]

non-linear fft

the function inside the FFT could be a delta, rect(.), signum or shifted versions and combinations of all of them depending on m1 and m2. It's very hard to say a general solution.