Basic Concepts in Signals and Systems
In this chapter, I shall tell you all you wanted to know about signals and systems but were afraid to ask your teacher. Starting with the definition of linear systems, some elementary signals are introduced, which is followed by the notion of time-invariant systems. Signals and systems are then coupled through impulse response, convolution and response to exponential signals. This naturally leads to Fourier series representation of periodic signals and consequently, signal representation in the frequency domain in terms of amplitude and phase spectra. Does this sound difficult? I shall simplify it to the extent possible, do not worry. Linear system response to periodic signals, discussed next, is then easy to understand. To handle non-periodic signals, Fourier transform is introduced by viewing a non-periodic function as the limiting case of a periodic one, and its application to linear system analysis is illustrated. The concepts of energy and power signals and the corresponding spectral densities are then introduced.
KeywordsLinear systems Signals Amplitude and phase spectra Response to periodic signals Non-periodic signals Fourier series and transforms Energy and power signals Spectral density
- 1.A.V. Oppenheim, A.S. Willsky, I.T. Young, Signals and systems. Prentice Hall (1983)Google Scholar