Efficient Design of CMFBs Using Two-Stage Frequency Response Masking

"A new method for designing narrowband cosine-modulated filter banks (CMFBs) is proposed based on the frequency-response masking (FRM) approach with masking filter decomposition. The resulting structure, the so-called FRM2-CMFB, presents a reduced computational complexity, and allows one to design filter banks with extremely high number of bands, where standard filter design methods fail to converge. Examples included, illustrate that the total number of coefficients of the CMFB prototype filter can be reduced to about 60% of the original FRM-CMFB structure, which does not use masking filter decomposition."