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Altera_Forum
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12 years ago

what is the difference between the sampling and clock frequency about FIR filter

hi,everyone.i want to ask whether the frequency of sampling and clock need to keep the same in use of fir compiler. according to my understanding,if they don't keep the same,the processing data rate ...
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Altera_Forum
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12 years ago

The input sampling rate of the FIR is the word rate of the data stream and will be equal to the ADC rate unless you have decimation stages inbetween. The actual sampling frequency is commanded by the asynchronous stream handshake, the sampling frequency number used in filter design is a nominal value for calculation.

The FIR clock frequency must be equal or greater compared to the sampling frequency, otherwise a data overflow occurs.

P.S.: As a simple case, use Fs = Fclk and set the input handshake signal to '1'.