一种应用于红外无线通信的改进型互补序列键控调制  

Improved Complementary Sequence Keying for Wireless Infrared Communications

作　　者：涂宜锋[1] 范平志[1] 袁伟娜[2] 郝莉[1] 

机构地区：[1]西南交通大学信息编码与传输四川省重点实验室,四川成都610031 [2]华东理工大学信息科学与工程学院,上海200092

出　　处：《铁道学报》2010年第5期65-69,共5页Journal of the China Railway Society

基　　金：国家自然科学基金(60772087);国家高技术研究发展计划(863计划)(2007AA01Z288);教育部新世纪优秀人才支持计划(NCET05-0795)

摘　　要：单个扩频序列的非完美自相关特性使多径信道条件下单序列扩频无线红外线通信系统中存在严重的多径干扰。互补序列键控(CSK)作为一种新的调制方式,采用二进制互补对(BCP)作为扩频序列。由于互补对具有完美的自相关特性,采用CSK的红外线系统能显著降低多径色散引入的多径干扰。然而,CSK在使用互补对时没有最大程度的利用其完美自相关特性,从而使系统的多径干扰无法完全消除。而且,CSK中BCP的选择过程极其复杂,限制了它的使用。通过对传统的CSK加以改进,互补对中的两个序列通过两个不同频率的子载波传送,从而达到完全消除多径干扰的效果,提高了系统的性能,改进型CSK中BCP的选择过程非常简单,避免了传统CSK中选择所涉及的庞大计算量,理论分析和仿真都验证了本文结论。Since the unitary spreading sequence which possesses perfect auto-correlation property does not exist,infrared wireless communication systems based on direct sequence spread spectrum suffer severe multipath interference in multipath channels.CSK is proposed as a new modulation scheme,in which BCP is employed as spreading sequences.Because of the perfect auto-correlation property of BCP,CSK can significantly reduce multipath interference.However,CSK does not make full use of the perfect correlation property of BCP,furthermore,selection of appropriate BCP for CSK involves lots of computation when the length of the spreading sequence is relatively long.We propose an improved CSK,in which data streams after spreading by two element sequence of BCP are transmitted via two different subcarriers.The improved CSK can completely eliminate multipath interference and provide simplicity and flexibility to the selection of appropriate BCP.System performance can be enhanced by employing improved CSK.Our conclusions are verified by theoretical analysis and simulation results.

关 键 词：互补序列键控 二进制互补序列 零相关区互补序列 

分 类 号：TP914.42[自动化与计算机技术]