Analog signals, Fourier Transform (FT), Fourier Series, continuous time LTI systems. Digital signals of infinite duration, Discrete Time Fourier Transform (DTFT), discrete time LTI systems, linear convolution, moving average filters, comb filters. Sampling process, Nyquist Theorem and aliasing, A/D converters, relation to analog domain. Digital signals of finite duration, Discrete Fourier Transform (DFT), relation to FT and DTFT, resolution of DFT and window selection, circular convolution and relation to linear convolution. Difference equations, Z Transform, introduction to FIR and IIR filters.