密集多径信道下IR-UWB信号同步捕获方法  

Acquisition of IR-UWB Signals in Dense Multipath Channels

作　　者：匡麟玲[1] 陆建华[1] 郑君里[1] 

机构地区：[1]清华大学电子工程系,北京100084

出　　处：《电子学报》2004年第F12期127-131,共5页Acta Electronica Sinica

基　　金：国家 8 63项目 (No .863 - 2 0 0 3AA1 2 32 1 0 )

摘　　要：超宽带 (UWB)信号的快速同步捕获是UWB通信系统中的关键问题 .本文提出一种分步同步捕获方法 ,首先采用两种次最优的最大似然估计算法进行粗搜索 ,然后在粗搜索获得的有限范围内利用最大值 阈值检测进行精估计 .该方法提高了密集多径信道下极窄脉冲形式UWB信号 (IR UWB)的捕获性能 ,并有效降低了计算复杂度和处理时间 .文中还根据IR UWB信号接收特点 ,从捕获能量的角度定义了捕获概率 .通过仿真评估了捕获能量对系统性能的影响 ,并对算法性能和参数选择进行了分析 .In dense multipath channels,rapid acquisition of Ultra Wideband (UWB) signals is a crucial problem due to very high pulse rate and extremely low per-path energy.This paper presents a two-stage acquisition scheme to improve acquisition performance in the Impulse Radio UWB systems.Specifically,two kinds of sub-optimal maximum-likehood criteria are proposed for a coarse search.Then,a maximum/threshold-crossing criterion is employed for a fine estimation within the obtained limited region.The probability of acquisition is redefined from the view of energy capture that may guarantee expected system performance after acquisition.The impact of captured energy on system performance,as well as,the selection of criterion parameters are evaluated and analyzed in terms of simulation.

关 键 词：超宽带 多径 同步捕获 

分 类 号：TN914[电子电信—通信与信息系统]