Signals can be divided into three categories ± continuous-time (analog) signals, discrete-time signals, and digital signals. The signals that we encounter daily are mostly analog signals. These signals are defined continuously in time, have an infinite range of amplitude values, and can be processed using electrical devices containing both active and passive circuit elements. Discrete-time signals are defined only at a particular set of time instances. Therefore they can be represented as a sequence of numbers that have a continuous range of values. . | Real-Time Digital Signal Processing. Sen M Kuo Bob H Lee Copyright 2001 John Wiley Sons Ltd ISBNs 0-470-84137-0 Hardback 0-470-84534-1 Electronic 1 Introduction to Real-Time Digital Signal Processing Signals can be divided into three categories - continuous-time analog signals discrete-time signals and digital signals. The signals that we encounter daily are mostly analog signals. These signals are defined continuously in time have an infinite range of amplitude values and can be processed using electrical devices containing both active and passive circuit elements. Discrete-time signals are defined only at a particular set of time instances. Therefore they can be represented as a sequence of numbers that have a continuous range of values. On the other hand digital signals have discrete values in both time and amplitude. In this book we design and implement digital systems for processing digital signals using digital hardware. However the analysis of such signals and systems usually uses discrete-time signals and systems for mathematical convenience. Therefore we use the term discrete-time and digital interchangeably. Digital signal processing DSP is concerned with the digital representation of signals and the use of digital hardware to analyze modify or extract information from these signals. The rapid advancement in digital technology in recent years has created the implementation of sophisticated DSP algorithms that make real-time tasks feasible. A great deal of research has been conducted to develop DSP algorithms and applications. DSP is now used not only in areas where analog methods were used previously but also in areas where applying analog techniques is difficult or impossible. There are many advantages in using digital techniques for signal processing rather than traditional analog devices such as amplifiers modulators and filters . Some of the advantages of a DSP system over analog circuitry are summarized as follows 1. Flexibility. Functions of a DSP .
