中文摘要：

本文提出了一种可用于宽带接收信号近似完全重构的余弦调制滤波器组。首先将滤波器组的设计转化为原型滤波器的设计,针对已有算法中幅度失真较大的问题,利用代价函数保证过渡带具有平方根余弦滚降特性,对通带截止频率进行调整使得原型滤波器的3dB通带截止频率等于理想滤波器的通带截止频率。文中还推导了以滤波器系数为变量,代价函数的闭合解表达式,并针对滤波器设计复杂度高的问题,采用了基于迭代求解原型滤波器的方法。实验仿真表明,该方法得到的调制滤波器组相较已有设计方法具有更好的性能。

英文摘要：

In this article, a kind of near perfect reconstruction cosine modulated filter banks which could be used to receive wideband signal is raised. First, the design of filter banks is transformed to the design of prototype filter. Considering the problem of amplitude distortion among existing algorithms, this article adopts cost function to make transition band has square root cosine roll-off. Cut-off frequency of passband is adjusted to ensure that the cut-off frequency of prototype filter＇ s 3dB passband is equal to that of ideal filter. In this article, close form solution expression of a cost function whose variable is filter factor is derived as well. To solve the problem of the high complexity of filter, a way based on iteration to solve prototype filter is adopted, The result of the simulation shows that modulated filter banks derived in this way perform better than those designed by existing method.