ABSTRACT
Digital filters are computational algorithms that transform input sequences of numbers into output sequences of numbers according to prespecified rules, hence yielding some desired modification to the characteristics of the input sequences. Digital filters are divided into two classes, namely, finite impulse response (FIR) and infinite impulse response (IIR). This chapter presents various design techniques for one-dimensional (1-D) FIR and IIR digital filters. It also presents a method for the design of a FIR filter with equiripple magnitude response using the Remez exchange algorithm. There are two approaches to the design of constant group-delay 1-D IIR digital filters. In the first approach, a 1-D analog filter is designed to meet the desired magnitude specification using any of the classical analog filters, namely, Butterworth, Chebyshev, and elliptic filters. In the second step, the parameters of the allpass function are determined through minimization of an objective function to achieve desired group-delay characteristics.
