Raymond Toy wrote:

>>>>>>"Tim" == Tim Wescott <[email protected]> writes:
>
>
> Tim> I'm trying to think of examples where using an anti-alias filter is a
> Tim> bad idea, or must at least be approached with extreme caution. I
> Tim> already know about control systems and video applications, and I
> Tim> believe that this is a big issue with EKG machines.
>
> Isn't there always some kind of anti-alias filter, whether you want it
> or not? Or are you saying that aliasing is better than whatever
> artifacts an anti-aliasing filter would produce?
>
> Just curious,
>
> Ray

There's always some sort of filtering going on, because no system has
infinite bandwidth. I _am_ saying, however, that in many instances
(such as EKG strips, video, or control systems) aliasing is better than
the artifacts that you'd get from a filter that you could honestly call
"anti-aliasing".

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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"Applied Control Theory for Embedded Systems" came out in April.
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