Re: FFT computation.
hi,
yeah , i understood that, but i have one more question then,
when we take fft, we maintain the ration of fin to fs equal to m/M where m and M are coprime numbers with M = 2^n.
so now say that my system is for subsampling, and fs = 20Mhz and i need input to be around 100Mhz for 4096 point fft.
using the clock generator i generated 20MHz clock and i also sync. the signal generator using 10MHz reference at the back of boxes. Now i need fin such that
fin/20M = m/4096 with m being a prime number right? which would give me 20480 for fin = 100MHz and for m to be prime i choose 20479 thus choosing fin = 99.99512Mhz ( close to 100Mhz and lying in the bin = 20479) but now when i try to generate this fin from the signal generator , and see both the clock and signal in scope with triggering from the clock waveform, the other one keeps moving.
I feel that even if i use this 10Mhz reference , i will not be able to trigger both clock and signal at the same time unless they both have frequency in multiples of each other.
please help me clarify this if i am mistaken
thanks.