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Altera_Forum
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16 years ago

FFT Megacore sourceexponent

Hallo I use the the FFT-Megacore from Altera and it works fine. But i´m not shure about the output exponent. For example in my Simultion the peak in my frequency spectrum was half the magnitude i...
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Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Yes i read the explenation in the userguide but it doesn´t work this way. I have a sine-wave with a magnitude from 256 while the output from the FFT Meagcore gives me a value of 128 for the according frequency. Additional it shows an exponent from -6 Bit (Bit 1, 3,4,5 is set, bit 0 and 2 not). That would be a factor of 2^6=64 which i would multiply with the value 128.

128*64 = 8192. That doesn´t fit or did i use a wrong way to calculate this?