An Improved and Simplified Approach for Designing Cosine Modulated Filter Bank Using Window Technique

摘要

An improved and simplified approach is presented for design of nearly perfect reconstructed cosine-modulated (CM) filter banks with prescribed stopband attenuation and channel overlapping. The method employs Kaiser window technique to design the prototype filter for filter banks with the novelty of exploiting spline functions in the transition band of the ideal filter instead of using the conventional brick-wall filter based on linear optimization of filter coefficients such that their value at frequency (ω = π/2M) is 0.707. The simulation results illustrate the proposed method and its improvement over other existing methods in terms of amplitude distortion (e am ), number of iterations (NOI), aliasing distortion (e a ) and computation time (CPU time).