M带余弦调制滤波器组的迭代设计算法  

Iterative design of M-channel cosine modulated filter banks

作　　者：蒋俊正[1,2] 水鹏朗[1] 周芳[3] 

机构地区：[1]西安电子科技大学雷达信号处理国家重点实验室,陕西西安710071 [2]桂林电子科技大学信息与通信学院,广西桂林541004 [3]桂林电子科技大学生命与环境科学学院,广西桂林541004

出　　处：《电路与系统学报》2011年第6期62-65,45,共5页Journal of Circuits and Systems

基　　金：国家自然科学基金项目(60872139);桂林电子科技大学博士科研启动基金(UF11014Y)

摘　　要：余弦调制滤波器组的设计问题通常是关于原型滤波器系数的非凸优化问题,设计的优劣很大程度上取决于设计问题的归结和所采用的求解算法。本文提出了一种基于迭代的设计方法,用于设计近似完全重构的余弦调制滤波器组。该方法通过松弛完全重构条件和运用迭代的思想,将余弦调制滤波器组的设计归结为一个易于求解的优化问题。在该优化问题中,原型滤波器的阻带能量被限定,然后迭代地优化原型滤波器的系数使得余弦调制滤波器组的重构精度达到较高的水平。文中给出的设计例子表明,相比于传统的设计方法,新方法使得设计的余弦调制滤波器组重构误差降低了约18dB,且阻带衰减提高了约6dB。In essence, the design of cosine modulated filter banks involves a non-convex optimization problem, and the performance of the design largely depends on the formulation of the design problem and the employed algorithm. An iterative algorithm is proposed to design nearly-perfect-reconstruction cosine modulated filter bank in this paper. Relaxing the PR condition and employing the iterative scheme can transform the design problem transformed into a simple optimization problem. In design, the stopband energy of the prototype filter is bounded. Then the prototype filter is iteratively optimized such that the filter banks with high reconstruction efficiency can be obtained. Compared with that of the conventional method, the improvement on the reconstruction error of the filter bank designed by the proposed method is approximate to 18dB and that on the stopband attenuation is about 6dB.

关 键 词：近似重构 余弦调制滤波器组 原型滤波器 重构误差 

分 类 号：TN713[电子电信—电路与系统]