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Altera_Forum's avatar
Altera_Forum
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16 years ago

FFT output?

This is probably going to be a simple question, but have been unable to find documentation to explain it. I'm running a 512 point 24 bit width data streaming FFT. My output is 24 bits with 6 bits o...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Normally, FFTs on FPGAs would be done in fixed point. If this is the case then exponent is the wrong word to use.

Fixed point numbers are just unsigned/signed integers offset by 2^n. In this case, with 24 bits, 6 magnitude (I assume) then this number represents 0-64 (or -32 to (just under) +32) with an accuracy to the nearest 2^-18.

it could still be a floating point, but I doubt it. Fixed point offers very good accuracy but sacrifices the range of data. But as it is basically just all integers it can be done very easily.