Frequency response masking based design of two-channel FIR filterbanks with rational sampling factors and reduced implementation complexity

Abstract

Previous work has shown that the implementation complexity of a two-channel filterbank (FB) with rational sampling factors can be reduced by exploiting the frequency-response masking approach (FRM) technique for designing finite-impulse response (FIR) building-block filters in this bank compared with the use of direct-form FIR filters. This paper shows that by designing FRM filters building the FB in such a way that the periodic filters are evaluated at the input sampling rate and the masking filters at the output sampling rate, the design as well as the implementation complexity can be further reduced when compared with the designs obtained by using other existing techniques. This is illustrated by means of an example.