A low-complexity multiplierless half-band recursive digital filter design

A low-complexity multiplierless design of a half-band recursive digital filter is presented. The filter structure is realized as a bireciprocal lattice wave digital filter. The filter coefficients are represented in a canonic signed-digit code with only two nonzero digits, and thus each filter coefficient can be implemented with only a single adder or subtracter. A fifth-order elliptic filter section is presented which requires only nine adders and five delays. Thus, a cascade of three or four of these fifth-order building blocks could be implemented on a single VLSI chip to obtain a high-performance half-band filter