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Altera_Forum
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10 years ago

Using fpga to implement long length FFT

Hello Guys, I got a long length data, and want to convert the data from time domain to frequency domain. These data from ADC, the sampling frequrency is 20MHz, and sampling time is about severa...
Altera_Forum's avatar
Altera_Forum
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10 years ago

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Hi kaz,

I'm sorry to confuse you, i mean which I/O data flow i should select for this application?

For FFT application, i saw someone else's project, who converted the ADC's data to signed value, is this necessary?

Thanks

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your fft ip should tell you. Normally ADC data that represents a signal swings around zero (no dc) if in 2's complement. But it could be using offset binary which needs inverting the sign bit.

At HDL level I expect std_logic_vector type.