I am using the System Generator (XILINX ISE 14.2) and MATLAB R2012a for Communication System Applications. FFT and IFFT (7.1) blocks don't work as I want. I am applying IFFT first, then FFT. After I apply them, I expect to get the original signal. I can not get the original signal as seen in Scope(Screen Shot). I added necessary screen shots for understanding the problem.
3. Note both the IFFT and FFT has some precision lost, so the IFFT input can not exactly the same with FFT output, but if you take care of the precision, you can very similar results between IFFT input and FFT output.
4. You can use sine wave as an input to do the test.