A dose of reality
Sometimes I argue with mathematicians about DSP. My view of DSP is an engineering one: firmly grounded in the idea of an objective reality. Signals, for me, signify something about the ‘real’ world - the results of measurements, or encoded messages that have some ‘real world’ meaning. Wikipedia agrees and in fact goes a bit further in saying: “In the context of signal processing, arbitrary binary data streams are not considered as signals, but only analog and digital signals that are representations of analog physical quantities.” Some mathematicians (and some DSP engineers) argue that the data in DSP is ‘just’ a set of numbers. Those numbers may represent some samples or properties of some thing in the real world, but once represented as a set of data they are ‘just numbers’. There is some truth in this, but I think it is a dangerous over-simplification. Let’s take a simple application to explore the idea. Suppose that I have a signal. We start with a set of samples of this...