Optimization of FIR filters synthesized using the generalized one-stage frequency-response masking approach

Frequency-response masking (FRM) approach is an efficient technique for significantly reducing the number of multipliers and adders in implementing sharp linear-phase finite-impulse-response (FIR) digital filters. It has been shown that further savings in arithmetic operations can be achieved by using the generalized FRM approach where the masking filters have a new structure. In both the original and the generalized synthesis techniques, the subfilters in the overall implementation are designed separately. The arithmetic complexity in the original one-stage FRM approach has been considerably reduced by using a two-step technique for simultaneously optimizing all the subfilters. Such an efficient algorithm was also proposed for synthesizing multistage FRM filters. In this paper, the two-step optimization algorithm proposed for the multistage FRM approach is adapted to the generalized one-stage FRM filters. An example taken from the literature illustrates the efficiency of the proposed technique.