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 analog electronics 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. Digital signals have discrete values in both time and amplitude; thus, they can be processed by computers or microprocessors. In this book, we will present the design, implementation, and applications of digital systems for processing digital signals using digital hardware. However, the analysis usually uses discrete-time signals and systems for mathematical convenience. Therefore, we use the terms 'discrete-time' and 'digital' interchangeably. Digital signal processing (DSP) is concerned with the digital representation of signals and the use of digital systems to analyze, modify, store, or extract information from these signals. Much research has been conducted to develop DSP algorithms and systems for real-world applications. In recent years, the rapid advancement in digital technologies has supported the implementation of sophisticated DSP algorithms for real-time applications. DSP is now used not only in areas where analog methods were used previously, but also in areas where applying analog techniques is very 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 system can be easily modified and upgraded with software that implements the specific applications. One can design a DSP system that can be programmed to perform a wide variety of tasks by executing different software modules. A digital electronic device can be easily upgraded in the field through the onboard memory devices (e.g., flash memory) to meet new requirements or improve its features. 2. Reproducibility: The performance of a DSP system can be repeated precisely from one unit to another. In addition, by using DSP techniques, digital signals such as audio and video streams can be stored, transferred, or reproduced many times without degrading the quality. By contract, analog circuits will not have the same characteristics even if they are built following identical specifications due …