Review of LTI systems; Fourier Transform for discrete-time signals and its properties, comparison with continuous-time F.T.; Z-transform and its inverse, region of convergence, properties, frequency selective filters, pole-zero locations and frequency response, stability, IIR and FIR filters, linear phase filters, response of first and second order filters; Signal analysis using the F.T., impulse function and complex exponential signal, modulation and frequency translation, duality, Fourier Transform of periodic signals, correlation, energy and power spectral density, Hilbert Transform, complex envelope representation, examples from AM, SSB-AM, and FM; Fourier Transform of finite-duration discrete- time sequences, relationship to discrete-time Fourier Series, circular convolution, FFT; Sampling of continuous-time signals, comb function, spectrum of sampled signals, relationship between spectra of discrete- and continuous- time representations, Nyquist's Sampling Theorem, aliasing, interpolation.