robert bristow-johnson <[email protected]> wrote in
news:C03382A7.1063A%[email protected]:

> in article [email protected] , Al
> Clark at [email protected] wrote on 03/07/2006 14:00:
>>
>> The even length FIR does not place a zero at PI. I never use these
>> since the In Phase tap would be 1/2 of a delay unit.
>
> i think it's an even length linear-phase FIR that does that. the
> delay of a symmetric FIR with N taps is (N-1)/2 . so N should be odd.
> (one thing is that if half-band symmetry is taken advantage of, every
> odd-indexed tap will have a zero coefficient which can cut the
> computational cost in half.)
>

I think that is what I said. I always use the odd length.

--
Al Clark
Danville Signal Processing, Inc.
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