Narrow-band and wide-band single filter frequency masking FIR filters

In this paper single filter frequency masking FIR filters are discussed. We briefly review the previously proposed lowpass narrow-band filters and propose a design method for highpass narrow-band filters. Wide-band filters are also discussed. The proposed approach uses several identical filters, except for periodicity, which are mapped to a single hardware structure using folding. This results in an area-efficient implementation with a small number of multipliers and adders at the cost of more memory. An example discusses the design of a wide-band lowpass filter and shows that substantial savings can be made.