摘要
直接序列扩频通信系统中,传统扩频序列m序列码元个数有限,且抗截获能力弱,混沌序列的抗干扰性能非常依赖序列的长度,Walsh(沃尔什)序列具有很好的正交性,但自相关性较差。为此提出一种混沌序列与Walsh序列的复合扩频序列,复合序列结合了混沌序列与Walsh序列的优点,即优良的抗截获性和互相关性,并且对混沌序列的长度要求不高。对复合序列的相关性及平衡性进行分析的同时,与混沌序列、Walsh序列、m序列的误码率进行了比较,仿真结果表明,复合序列具有良好的相关性和平衡性,适用于直扩系统,且抗干扰性能良好。
In the direct-sequence spread spectrum system, m sequences are traditional spreading sequences, whose codes＇ length is limited, and their ability of anti-intercepting are also very weak. Chaotic sequences＇ anti- jamming performances are dependent on the length of the sequences seriously, Walsh sequences are orthogonal, but with poor correlation. This paper proposed a composite spread spectrum sequences based on the chaotic sequences and the Walsh sequences ; the composite sequences combine the advantages of the two sequences of excellent anti-in- tercepting and cross-correlation. Moreover, the chaos sequences＇ length is not demanded especially. And then the composite sequences＇ correlations and balances were analyzed, and the BER （bit error rate） of composite se- quences＇ and that of other sequences： the chaotic, Walsh and m sequences were compared. The simulation results show that the composite sequences are applicable in the DS system for their good performances of correlation, balance and anti-jamming.
出处
《计算机仿真》
CSCD
北大核心
2013年第11期173-176,201,共5页
Computer Simulation
基金
国家高技术研究发展计划(863计划)(2012AA80XX03G)
关键词
直接序列扩频
复合序列
混沌序列
沃尔什序列
误码率
Direct sequence spread spectrum （DSSS）
Composite sequences
Chaotic sequences
Walsh se-quences
Bit error rate （BER）
