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Altera_Forum's avatar
Altera_Forum
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15 years ago

cascaded IFFT WITH FFT

hello,

I try to cascad an IFFT(v2.2.1) with an FFT(v2.2.1) in a OFDM design for channel estimation. I have simulated the entire chain with MODELSIM and all data given by the FFT is the same such as my SCILAB simulation chain. But when I integrate my design on FPGA (here STRATIX S80), the data obtained by the FFT output (observe with SignalTap) are not the same such as simulated, the design lost 8 samples. I have verify the signal for FFT CTRL, but i don't find where is the problem? if someone can help me!

thanks

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Hello,

    What do you mean by the design lost 8 samples ? You entered a sequence of N samples and on the ouput you have a sequence of N-8 samples ?

    Jérôme