摘要
本文研究大多普勒频移低信噪比情况下直扩系统中的PN序列捕获问题,评估了频偏及不同相关长度对匹配滤波器输出相关峰值的影响,分析了使用分段匹配时系统抗频偏性能以及对检测概率的影响。采用多次最大值技术避开了判决门限问题,并计算了采用此种方式时系统的检测概率,提出了一种新的频率一相位二维搜索的策略,减少了PN码捕获的时间。
The subject about the sequence acquisition under large frequency offset and low signal to noise ratio in DS systems was researched, and evaluation of the influence on system detection-rates and ability against frequency offset when sectional matching mode implemented was presented in this paper. Multi-accumulated correlation value method was adopted to avoid setting determination threshold,and system detection-rates were calculated under this circumstance. At last, a new acquisition strategy based on Two-dimensional searching was proposed to reduce the time consumption of PN code acquisition.
出处
《国外电子测量技术》
2007年第7期18-20,共3页
Foreign Electronic Measurement Technology
关键词
大频偏
PN码捕获
分段匹配
large frequency offset
PN code acquisition
sectional matching
