High-Q switched-capacitor BandPass Filter?

[mikem]

Dave VanHorn wrote:

Would you be thinking of a boxcar averager?

I read about "boxcar averaging algorithm", and it seems to be
a way to minimize noise by oversampling and low-pass filtering.
Does this provide a means of suppressing the higher order
harmonics (second, third, etc) while passing only the
fundamentanal?

What sort of phase shift does it introduce?

MikeM

 

[Dave VanHorn]

"mikem" <mikem@bogus.adr> wrote in message
news:c8t4o4$o67$1@coward.ks.cc.utah.edu...

Dave VanHorn wrote:

Would you be thinking of a boxcar averager?

I read about "boxcar averaging algorithm", and it seems to be
a way to minimize noise by oversampling and low-pass filtering.

I'm referring to the hardware implementation.
It's an averager, not a low-pass.
If you have a wave that has a big transition in it, and your boxcar has
enough resolution, then you get the transition nicely, even though the
filter has a bandpass that's fractional hz.

Does this provide a means of suppressing the higher order
harmonics (second, third, etc) while passing only the
fundamentanal?

No, but you can do a front end filter that will.
Even order harmonics drop out destructively.

What sort of phase shift does it introduce?

None.

MikeM

 

[Jerry Avins]

Dave VanHorn wrote:

"mikem" <mikem@bogus.adr> wrote in message
news:c8t4o4$o67$1@coward.ks.cc.utah.edu...

Dave VanHorn wrote:


Would you be thinking of a boxcar averager?

I read about "boxcar averaging algorithm", and it seems to be
a way to minimize noise by oversampling and low-pass filtering.


I'm referring to the hardware implementation.
It's an averager, not a low-pass.
If you have a wave that has a big transition in it, and your boxcar has
enough resolution, then you get the transition nicely, even though the
filter has a bandpass that's fractional hz.



Does this provide a means of suppressing the higher order
harmonics (second, third, etc) while passing only the
fundamentanal?


No, but you can do a front end filter that will.
Even order harmonics drop out destructively.


What sort of phase shift does it introduce?


None.

True but possibly misleading. It introduces a delay that is the same for
all frequencies.

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

True but possibly misleading. It introduces a delay that is the same for
all frequencies.

True. It's not what you usually think of, when you think of a filter.

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

I like it!