When a timeinvariant system is cascaded with a timedelay
system, the order of the two systems does not matter.
Thus we can delay the input \(x[n]\) and then filter it, or we
can filter \(x[n]\) and then delay it.
The following two demos show the details of these cascaded
implementations for two different filters.
1st difference filter

Here is a block diagram example of time invariance with the 1st difference
filter.
Click on any of the blocks, the input or the output for a closeup.

5point averager

Here is a block diagram example of time invariance with the 5point
averager.
Click on any of the blocks, the input or the output for a closeup.
