摘要
本文首先推导出过采样滤波器组精确重构的条件，由于此时所需的约束条件数比临界采样时少，因而可以设计出频域衰减特性更好的滤波器组。然后提出了精确重构约束条件下原型低通滤波器的一种新的设计方法，采用矢量的二次型约束优化算法。该算法优化方便，收敛速度快，与其它方法相比，滤波器的阻带衰减大。
The constraints of oversampled cosine-modulated filter banks with perfect reconstruction(PR) are firstly educed in this paper. Because its constraints are less than that in the critically sampled case, we can lead to PRLP prototypes with stopband attenuation being much higher than that in the critically sampled PR case.Then we present a method for designing prototype filter based on an quadratic-constrained minimization problem.The solution of the minimization problem converges very quickly since the cost function as well as the constraints are quadratic functions with respect to the unknown parameters. Compared with other design methods, the proposed technique yields PR filter banks with much higher stopband attenuation.
出处
《通信学报》
EI
CSCD
北大核心
2001年第8期66-71,共6页
Journal on Communications
关键词
过采样
余弦调制滤波器组
精确重构
oversample
cosine-modulated filter banks
perfect reconstruction
