On a modified structure for cosine-modulated filter banks using the frequency-response masking approach

In this paper, we propose a cosine-modulated filter bank (CMFB) design using the frequency-response masking (FRM) approach in which the interpolation factor L of the base filter is approximately an even-multiple of the number M of subbands. In such a case, a realizable maximally decimated structure requires a large computational complexity for the filter bank. Instead, we employ an over-sample FRM-CMFB structure to address the problem, and combine adjacent subbands to achieve the desired number of bands in the original design. The result is an FRM-CMFB structure with reduced computational complexity.