一种设计近似完全重构非均匀余弦调制滤波器组的新算法

Novel Method for Designing Near-perfect-reconstruction Nonuniform Cosine Modulated Filter Banks

该文提出了一种设计近似完全重构非均匀余弦调制滤波器组的新算法。针对现有合并算法中非均匀滤波器组性能无法直接控制优化的缺点,新算法把非均匀滤波器组的设计问题归纳为一个关于原型滤波器的无约束优化问题,其中目标函数是非均匀滤波器组传递失真与原型滤波器阻带能量的加权和,最后利用线性迭代算法求解该优化问题。理论分析和数值实验表明,新算法获得的非均匀余弦调制滤波器组比现有算法设计的滤波器组整体性能更佳。

This paper proposes a new algorithm to design near-perfect-reconstruction nonuniform Cosine modulated filter banks. Due to the infeasibility of directly controlling the performance of Nonuniform Filter Banks （NUFBs） in the existing combined algorithms, the design problem boils down to an unconstrained optimization problem with respect to the Prototype Filter （PF）, which minimizes a weighted sum of the transfer function distortion of the NUFBs and the stopband energy of the PF. The optimization problem can be efficiently solved by utilizing linearizing iterative approach. The theoretical analysis and numerical experiments are carried out to show that compared with the existing methods, the proposed method can lead to NUFBs with better overall performance.