This textbook presents the theory of continuous-time and discrete-time signals and systems and shows how it can be used to solve analytically different problems. The book is dedicated to engineering students who are interested in mathematical methods used to solve real technical problems connected with signals and systems. The book covers, both in continuous- and in discrete domains, analysis of signals in time domain; orthogonal signal representation including Fourier series; convolution and correlation of signals; analysis of signals in the frequency domain and signal sampling, including...