Analysis and Design of Discrete-Time Filters
Oktay Alkin · 2025
Chapter 8 focuses on analysis and design of discrete-time filters. The idea of processing continuous-time signals using discrete-time filters is introduced. Polezero placement design methods are discussed for two types of filters, namely resonant bandpass filters and notch filters. Afterwards, the distinction between infinite impulse response (IIR) and finite impulse response (FIR) filters is given. Design of IIR filters by transforming analog prototypes to discrete-time filters is discussed. A brief review of analog prototype filter design methods is provided. Various transformation methods are discussed including the impulse invariance method and the bilinear transformation. The coverage of FIR filter design begins with a discussion of the significance of having a linear phase characteristic, and the types of symmetries in the impulse response that lead to linear phase. Various design methods for FIR filters are covered including Fourier series design using window functions, frequency sampling design method, least squares design method and the Parks-McClellan technique. MATLAB exercises for the chapter deal with using MATLAB for designing various IIR and FIR filters. Case studies are provided for cleaning up an ECG signal with sinusoidal interference using a notch filter, and simulating the vibrations of a plucked string fixed between two points.