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Signals and systems. With Ian T. Young. (English) Zbl 0539.93001
Prentice-Hall Signal Processing Series. London etc.: Prentice/Hall International. XIX, 796 p. \$ 24.95 (1983).
The book is intended as a text for an undergraduate course in signal and systems. It contains: a Preface; 11 chapters, (1) Introduction, (2) Signals and Systems, (3) Linear Time-Invariant Systems, (4) Fourier Analysis for Continuous-Time (shortly c-t) Signals and Systems, (5) Fourier Analysis for Discrete-Time (shortly d-t) Signals and Systems, (6) Filtering, (7) Modulation, (8) Sampling, (9) The Laplace Transform, (10) The z-Transform, (11) Linear Feedback Systems; an Appendix, Partial Fraction Expansion; Bibliography and an Index.
Usually signals and systems are treated in c-t or in d-t version separately. This is understandable, because the tools to handle them are quite different. Many attempts have been made to treat them within a unique mathematical formalism. But we think that no success has been obtained.
In the book another way is taken: the methods for the analysis of the two kinds of systems are developed in parallel. By this way one can draw on the similarities in order to share the intuition in each domain and at the same time to exploit the differences between them in order to strengthen the distinct properties of each. The first five chapters contain standard facts from the signals and systems theory that can be found elsewhere. But it is worthy to note that in each situation where it is possible block diagrams are drawn in order to get a physical insight of the mathematical facts.
Chapter (6) treats the filtering problem and various examples of data smoothing are given. At this moment we remark an interesting feature of the book: while the common texts in signals and systems are illustrated with examples taken from electronic systems, this text contains other interesting examples taken from economy, mechanics, etc. We agree with the opinion of the authors that a course of signals and systems should be taught in every engineering school. The next chapter (7) offers a view of the main modulation methods.
Chapter (8) is in some way a key of the book because it treats the passing from c-t signals to d-s signals and conversely, i.e. sampling of c-t signals and recovering them from their samples. Chapters (9) and (10) present the mathematical tools used for the analysis of c-t and d-t signals and systems. The Nyquist criterion and other criteria are given in the last chapter. Besides the deep connection between the theory and various applications of it, a lot of exercises (over 350) are proposed to the reader. They introduce the reader to modern applications such as Fast Fourier Transform and so on. At the end a splendid selective up-to-date bibliography is given for further study. As we said, the book is an attempt to give a parallel and contrastive treatment of c-t ad d-t signals and systems. We can clearly say that the attempt was successful.
Reviewer: D.Stanomir

##### MSC:
 93-01 Introductory exposition (textbooks, tutorial papers, etc.) pertaining to systems and control theory 94-01 Introductory exposition (textbooks, tutorial papers, etc.) pertaining to information and communication theory 93C05 Linear systems in control theory 44A10 Laplace transform 42A99 Harmonic analysis in one variable 44A55 Discrete operational calculus 60G35 Signal detection and filtering (aspects of stochastic processes) 62M20 Inference from stochastic processes and prediction 93C99 Model systems in control theory 93C55 Discrete-time control/observation systems 93C57 Sampled-data control/observation systems 93E11 Filtering in stochastic control theory 93E14 Data smoothing in stochastic control theory 94A12 Signal theory (characterization, reconstruction, filtering, etc.) 94A14 Modulation and demodulation in information and communication theory