ABSTRACT
Discrete-time signals are the signals defined only for a discrete set of values of the independent variable of time. There are three types of conversion of the independent variable of a signal: time shift; time reversal; time scaling. Discrete-time signals are generally classified into two categories: finite energy signals; and finite power signals. Various algorithms of numerical analysis are discrete-time systems. A special category of discrete-time systems is that of the digital systems. These are systems whose inputs and outputs are digital signals. A large part of the modern hardware corresponds to digital systems. In modern technology, in order to study a system, four techniques are followed: system analysis; system modeling; system identification; and model validation. This chapter discusses the various categories of discrete-time systems.
