This article is rated Start-class on Wikipedia's content assessment scale. It is of interest to the following WikiProjects:
Systems Mid‑importance This article is within the scope of WikiProject Systems, which collaborates on articles related to systems and systems science.SystemsWikipedia:WikiProject SystemsTemplate:WikiProject SystemsSystems articles Mid This article has been rated as Mid-importance on the project's importance scale. This article is within the field of Control theory.

Does not have an impulse response in the normal sense. The system can be characterized by an impulse response except the impulse response must be known at each and every time instant. - dont we have to know that it is linear for that to be true?

" Linear time varying processes such as amplitude modulation occur on a time scale similar to or faster than that of the input signal. In practice amplitude modulation is often implemented using time invariant nonlinear elements such as diodes.

The Discrete Wavelet Transform, often used in modern signal processing, is time variant because it makes use of the decimation operation. " - I dont think this is good example of time variant SYSTEM... 62.245.124.84 10:19, 3 May 2007 (UTC)Reply[reply]

Right, there aren't any good examples. That's the problem with this page, it doesn't refer to anything or you could say it refers to practically everything except the interesting problems, the ones we can solve. Interferometrist (talk) 14:10, 6 July 2021 (UTC)Reply[reply]

This topic is not notable and the page should be deleted for that reason. However failing that we can merge any useful content on this page (if any) into the actual subject where time invariance is an issue. Then the significance of "time-variant" (a term not used in practice) is that it isn't time-invariant, which I guess can be pointed out in case some reader thought that everything was.Interferometrist (talk) 14:48, 6 July 2021 (UTC)Reply[reply]