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Altera_Forum
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8 years ago

Estimation IIR filter resources

Hi, In my application I will need implement high order (4), IIR, Butterworth, Low Pass filter, with cutoff frequency (-3dB) of ~1Hz and stop band of ~10Hz, with attenuation of -80dB. The input si...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
8 years ago

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A cutoff f 1/50k is possible with large fir or small iir but a transition band of -80dB at 10/50000 is just not realistic for fir or iir.

This requirement is too drastic for such a slow system.

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It's unhandy but feasible. There can be reasons why you want to operate a filter with this specification at 50 kS/s sampling rate. But it can be expected that a multi-rate design results in overall lower resource utilization.