一种基于近似理想重构余弦调制滤波器组的DSSS变换域干扰抑制方法  

A Transform-Domain Interference Suppressing Method in Spread Spectrnm Systems Based on Near Perfect Reconstruction Cosine-Modulated Filterbank

作　　者：黎剑[1] 张家树[1] 

机构地区：[1]西南交通大学信号与信息处理四川省重点实验室,成都610031

出　　处：《电子与信息学报》2007年第9期2128-2131,共4页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(60572027);教育部新世纪优秀人才支持计划(NECT-05-0794);电子科技大学抗干扰国家级重点实验室基金项目(51434110104QT2201)资助课题

摘　　要：针对在变换域干扰抑制方法中子带滤波器组的阻带衰减性能不够理想而造成窄带干扰扩散的问题,该文提出了一种使用近似理想重构余弦调制滤波器组的窄带干扰抑制方法。近似理想重构滤波器组在设计上具有更大的灵活度,能够实现更高的阻带衰减。具有高阻带衰减特性的滤波器组能够更好地将窄带干扰信号变换到少数几个子带上,从而利用门限检测的方法能更好地对窄带干扰加以抑制。仿真结果表明,相对于传统的重叠变换滤波器组,使用近似理想重构余弦调制滤波器组能够显著提高变换域接收机的抗窄带干扰能力。The filterbank without good stopband attenuation will cause the narrowband interference power diffusing in more subbands, and the interference suppressing in transform domain may become less effective and more difficult. Accordingly, a interference suppression method is proposed based on the Near Perfect Reconstruction （NPR） cosine-modulated filterbank, which has more freedom degree in design and is more likely to implement the high stopband attenuation. The filterbank with the characteristic of high stopband attenuation can transform the narrowband interference in less subbands, and therefore has more efficiency in suppressing the narrowband interference by the conventional threshold-detecting. Simulating results show that the performance of the transform-domain interference suppression method using the NPR filterbank is better than the one using the perfect reconstruction filterbanks such as the lapped transform filterbank.

关 键 词：余弦调制滤波器组 近似理想重构 高阻带衰减 变换域处理 

分 类 号：TN911.4[电子电信—通信与信息系统]