1. Fundamentals of signal processing

Processing a signal means using the most appropriate techniques to extract the maximum amount of information from it, usually in the presence of interfering noise. Signal processing methods have been developed over the last thirty years or so, and the need for them has arisen in a number of fields. First of all, of course, when we want to highlight a low-amplitude signal on which we have a greater or lesser amount of information, but which is completely masked by parasitic noise due to the environment or to the measuring instruments themselves. This situation arises very often in laboratories, where researchers are working on increasingly complex problems involving very weak effects, the source of signals completely drowned out by significant noise.