Design of cosine-modulated filter bank prototype filters using the frequency-response masking approach

We use the frequency-response masking (FRM) approach to design prototype filters for cosine-modulated filter banks in the nearly perfect reconstruction case. With such an approach, it is possible to design a FRM filter with overall order almost equal to the direct-form FIR design, with only slight changes in the values of the inter-carrier and inter-symbol interferences and the attenuation of the bank filters. The result is an efficient design with reduced number of multipliers for the overall structure.