A method for synthesizing multiplierless FIR digital filters with narrow transition widths

In this paper, a method for synthesizing multiplierless linear-phase FIR digital filters with narrow transition widths is presented. The proposed method is developed based on the structure of interconnecting the identical subfilters by using a few tap coefficients (Saramaki, 1987). In the proposed method, the subfilter's coefficients and the tap coefficients are searched in the discrete powers-of-two coefficient space, respectively, to make the whole filter structure become multiplierless. A simulation example shows that a sharp-cutoff multiplierless filter with tight specification on the maximum allowable ripples can be easily designed using the proposed design technique. (C) 1997 Elsevier Science B.V.