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Altera_Forum
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14 years ago

FFT Megafunction - bit reversed or not

Hi all, using the FFT megafunction (fixed,streaming architecture), I have been assuming the data is natural order (user guide could be clearer?) Am I wrong? My sim. output looks wrong ...
Altera_Forum's avatar
Altera_Forum
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14 years ago

If your input is real sine (imag of zero) then you will get two equal mirrored peaks.

If your input is complex sine/cos (well balanced in amplitude and phase) then you get one peak only. If it is complex but unbalanced then the peaks become unequal. The real case is the extreme subset when imbalance is maximum (imag = 0)