Implementation of IIR-like filter blocks in cascade for generating narrow transition-band linear-phase FIR filters

The authors have recently proposed a class of filter structures requiring small number of components for designing narrow transition-band linear-phase FIR filters. The efficiency of the proposed structures was based on the fact that IIR filters have been exploited to design linear-phase FIR filters. The integration of IIR filters in the structure calls for special considerations in the implementation to counter the progressive round-off noise generated by the IIR filters. The main focus of this paper is to present a realization of the proposed design in such a manner that the generated round-off noise is reduced drastically. Other implementational aspects, such as minimization of the delay elements in the structure has also been addressed.