Xilinx LogiCore FFT 3.2

Hi All,

I am using the Xilinx Core Genenator to generate the FFT core for my
design. But when I tried to
simulate with a random noise input with N = 128, the output xk_re and
xk_im are all between
-5 and 5 which is obviously not the correct result. Matlab result show
the fft output in order of 100.

I used fixed length of 128 and tried Radix-4 and Radix-2 implemenation
options with 16bit data,
16 bit phase factor and scaled options. The output is in natural
order.  But all of these
settings produce the same result.   I checked the input and out
signals, they seem to be all correct.

There must be something I missed here but I just could not figure out
now. I would greatly appreciate it
if anybody help!

Thanks a lot!

Regards,
William

Hi william, there is a exponent part, did you take that into account ??

rgds bijoy