New classes of frequency-response masking FIR filters

This paper introduces new classes of frequency-response masking (FRM) FIR filters. In the FRM approach, the overall filter makes use of periodic model filters and nonperiodic masking filters which makes it possible to obtain FIR filters requiring few arithmetic operations even when the transition band is narrow. A reason for considering the new classes of FRM filters in this paper is that they are useful for multirate filter banks. The overall filters can be designed by separately optimizing the model and masking filters. Design examples are included.