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Altera_Forum's avatar
Altera_Forum
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11 years ago

problem with FIR IP

FIR IP filter output waveform shake up and down , Input signal contains the useful signal and the noise signals , so the frequency of the noise signal may be greater than half of the sam...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

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Can you describe the signal you are sampling (its amplitude and frequency), and the ADC you are using? Sampling at 25MHz seems like too much oversampling.

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In the designed system , 100KHZ and 200KHZ signals are sampled by ADC through 25MHZ sampling rate （ its amplitude is MV level ）, by system processing , FIR IP filter final input includes a DC signal(which is generated after system processing) and three high-frequency signal(100KHZ , 200KHZ ,300KHZ) and maybe some high frequency noise signal.

what I want is only the DC signal , so I'm confused how to set the FIR IP filter's parameter ( Fs and Fc ) ???

thank you very much for your reply !