Subband adaptive filtering using approximately alias-free cosine modulated filterbanks

In this paper, we use a class of cosine modulated filter-bank (CMFB) with approximately reconstruction property for subband adaptive filtering. We show that even after the subband filters are included, the CMFB maintains the approximately alias-free property. In earlier designs, when the filterbank has real coefficients, the alias-free property is usually destroyed after subband filters are inserted. The CMFB has real coefficients and the computational complexity for filtering and subband adaptation is less than that of complex-valued filterbanks. Numerical simulations will be given to demonstrate its approximately alias-free property and fast convergence.