Scott Seidman wrote:
> Jerry Avins <[email protected]> wrote in news:
> [email protected]:
>
>> It approximated linear phase better than most analog filters, but it
>> isn't very good compared to symmetric FIRs. The rolloff can be
>> disappointing. http://en.wikipedia.org/wiki/Bessel_filter
>
> The man wants an anti aliasing filter. I suppose you could sample fast
> enough so the phase in the frequency band of interest is close enough to
> zero, and then do whatever FIR/decimation you want to, but I assumed we
> were still in the analog world.

The FIR was just for comparison. The Bessel can be cuite goog well below
cutoff, but the plot in the link I posted shows that one needs a lot of
oversampling to use it. Bessel can beu useful with the right tradeoffs.

Jerry
--
Engineering is the art of making what you want from things you can get.
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