N. T. wrote:
> You may call it whatever you want, but it is "A simple moving average
> (SMA) is the unweighted mean of the previous n data points".

Yes, which is also known as a box filter.  The properties of such a filter
are well known.  It has one important characteristic in that the gain at on=
e
particular frequency and its integer multiples is zero.  But otherwise, its
high frequency rolloff and step response properties are not particularly
great for most simple noise filtering applications.

> It can be good and it is widely used in the industry.

This only shows how few people paid attention in digital signal processing
class.  Tell a filter-ignorant engineer to do something to reduce high
frequency noise, and you get a box filter most of the time.  That only show=
s
it's conceptually obvious, not that there aren't better tradeoffs for most
applications.


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