Talk:Impulse response

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Contents 1 questions 2 headers 3 Diagram 4 Cleanup 5 IMAGES

[edit] questions

(i) The mathematical discussion seems to be based on discrete-time signals. Why? The same discussion could be written using time-continuous functions, resulting in a more general description (in mathematical terms). Or, to put it another way: I get the impression that the article relates to digital signal processing. While the impulse response certainly is important in digital signal processing, it surely is not limited to this discrete-time application. I therefore suggest to rewrite the formulae for the more general case of time-continuous functions. What dou you think?

(ii) Why not use round brackets?

The square brackets are presumably related to the first point you note: the apparent focus on discrete time. It is a bit odd in that context that only the Dirac and never the Kronecker delta function is mentioned. I personally think the huge string of equations is a bit hard to follow and the rest seems disorganized. I'll try to make some edits to the structure of the article in the next few days. Aluvus 08:10, 26 May 2006 (UTC)

I have no idea what the long string of equations is trying to show, in fact it seems the whole content is contained in the last few lines: T[x] = folding(x, L[delta]). E.g. the part about \sum_k x[k] \delta[n-k] lying in the domain of T is redundant, as this sum is identical to the original x[n] by definition. 84.150.103.113 20:00, 4 February 2007 (UTC)

(iii) Impossible?

The article says this: "While this is impossible in any real system, it is a useful concept as an idealization." For an analog system, yes, there is no such thing as an ideal impulse response. However, isn't it possible to have an impulse response from a digital system with discrete samples? (I'm not an expert so I could be wrong about this.) Steveha 04:02, 7 June 2006 (UTC)

Yes, the impulse used is not a Dirac Delta in this case, for the simple reason that you can't go to infinitely short times when discretely sampling. The signal corresponding to the Delta function is the 1 for the zeroth sample, and 0 otherwise. 84.150.103.113 20:00, 4 February 2007 (UTC)

OTOH discrete sampling can be reasonably elegantly analysed in terms of a fixed spaced sequence of dirac delta's, so there is an impulse response when the impulse coincides with one of the sequence.WolfKeeper 20:13, 4 February 2007 (UTC)

Concering (i) I'm saying that " Similar results hold for continuous time systems." I think it is trivial to write down integrals instead of sums.--karatsobanis 20:33, 27 July 2006 (UTC)

[edit] headers

This page needs to be split up into sections so its easier to read. Fresheneesz 05:09, 19 April 2006 (UTC)

[edit] Diagram

This needs some pictures. —Ben FrantzDale 20:24, 16 May 2006 (UTC)

[edit] Cleanup

The voice of the article isn't quite encyclopedic. —Ben FrantzDale 04:09, 28 May 2006 (UTC)

[edit] IMAGES

ALL IMAGES ARE SHOWING UP AS EMPTY BOXES. might be temporary.