Subband adaptive filtering with time-varying nonuniform filter banks

A technique is presented for subband adaptive filtering with nonuniform filter banks. The bandwidth allocations of the subband analysis and synthesis filters are adapted to the spectral characteristics of the input data in such a manner as to minimize an objective function built from the subband error powers. The nonuniform filter bank structure allows for fast convergence times for high order systems with a reduced mean square error relative to the uniform subband scheme. Results are presented for the case of a nonstationary system with time-varying spectral characteristics.