A new structure of prefilters for FIR digital filters
Naoyuki Aikawa, Masamitu Sato · Electronics and Communications in Japan (Part III Fundamental Electronic Science) · 1989
Abstract The cascade of a prefilter and an equalizer is effective for realizing an FIR digital filter with few multipliers. Generally, the number of multipliers in the entire filter decreases as the prefilter response becomes closer to a given specification. This paper proposes a new structure of pre‐filters which can produce a response closer to the specification than a conventional structure. Furthermore, a new method of cascading the prefilters, and which improves both the passband and stopband characteristics, is described. In this method, a pre‐filter cascaded with the preceding ones is designed so as to compensate their approximate characteristics. the small passband ripple and large stopband attenuation can be realized by using the proposed prefilters and an equalizer with only few multipliers.