Re: FIR filter question

On Nov 26, 3:08 am, Jamie Morken <jmor...@xxxxxxx> wrote:
Hi,

When using a lowpass FIR filter, with 100kHz sampling and 1kHz -3dB
cutoff frequency, is there a minimum number of coefficients required for
the filter to operate properly similar to a Nyquist minimum?  I was
thinking that there would be 100 or even 200 coefficients required since
the cutoff frequency is 100 times lower than the sampling frequency so
that the low frequency data can remain in the coefficient data long
enough, but I am not sure if this is correct..

cheers,
Jamie

I have a website that allows you to buils and see simple FIR filters.
It is located here. Perhaps this will help you get some insight.

http://www.fourier-series.com/fourierseries2/convolution.html
.

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