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Topic: Is Match Filtering Ever Used To Recover the Signal's Original
Wave Form In Optics?

Replies: 13   Last Post: Apr 15, 2012 1:00 AM

 Messages: [ Previous | Next ]
 BretCahill@peoplepc.com Posts: 487 Registered: 6/24/08
Re: Is Match Filtering Ever Used To Recover the Signal's Original
Wave Form In Optics?

Posted: Apr 15, 2012 1:00 AM

> >>>> What does further processing get you in terms of information?
>
> >>> Supposing you need to squelch when the first derivative of the
> >>> original signal exceeds a threshold?

>
> >>> How do you do that with the convolution?
>
> >>>> A pretty picture (i.e. waveform) that by visual inspection you can say:
> >>>> "SEE? It looks the same as what I started with!! ??

>
> >>> A visual comparison of the filtered signal with the template _is_ nice
> >>> to have to get a quick idea of the noise problem.

>
> >>> Bret Cahill
>
> >> Agreed
>
> > Here, try again:
>
> > Supposing you need to squelch when the first derivative of the
> > original signal exceeds a threshold?  How do you do that with the
> > convolution?

>
> How do you do that with a matched filter?

Recover the original signal by taking the square root of the output --
the convolution -- in the frequency domain. Then take the inv. FFT.
There may be some folding adding and splicing involved.

Bret Cahill