ABSTRACT
The main objective of this chapter is to introduce the fundamentals of discrete-time signals and systems and to provide a working knowledge necessary for performing signal processing of common signals derived from the human body. Ultimately, any engineering analysis must be compared with experimental data both for validation and for estimating the sensitivity of the system to small changes in parameter values. Modern biomedical instrumentation predominantly produces electrical signals as outputs, no matter what physical variable is being measured. Also, data acquisition is invariably linked to the digital computer. This section, therefore, presents the elements of signal processing necessary for a biomedical engineer, both from a theoretical as well as from a practical point of view. The chapter starts with the major concept of time to frequency domain transformation. It then introduces the basic building blocks required to perform this analysis in the digital domain. This includes digital signals and their mathematical representation. Once this is accomplished actual biomedical examples are given to demonstrate major concepts such as aliasing and quantization.
