电讯技术2017，Vol.57Issue(11)：1260-1265,6.DOI:10.3969/j.issn.1001-893x.2017.11.006
弱信号下"北斗"接收机NH码的快速捕获
Fast Acquisition of Neumann-Hoffman Codes for BDS Receivers in Weak Signal Environment
摘要
Abstract
Longer integrations can efficiently enhance the acquisition sensitivities of the Global Navigation Satellite System ( GNSS ) . However, the performance of Beidou System ( BDS ) medium Earth orbit/in-clined geostationary orbit( MEO/IGSO) satellite signal acquisition can be seriously affected by the second-ary Neumann-Hoffman ( NH ) codes. For the NH codes, bit-flipping may occur in each signal period (1 ms) , which will affect the integration time and thus lower the acquisition sensitivities. To solve the prob-lem, a symbol-based exhaustive searching algorithm is presented. The errors caused by the NH codes flip-ping are eliminated by traversal searching of all the possible coding combinations. Experiment results show that the presented algorithm can improve the acquisition successful rate 2 dB at least, especially for weak signals. Furthermore, the algorithm can provide more accurate carrier frequency.关键词
"北斗"卫星导航系统/弱信号捕获/NH码/相关累积/码元遍历搜索Key words
Beidou system ( BDS )/weak signal acquisition/NH code/coherent integration/symbol-based exhaustive searching分类
信息技术与安全科学引用本文复制引用
洪冰清,覃新贤,刘聪聪,陈海强,齐月敏..弱信号下"北斗"接收机NH码的快速捕获[J].电讯技术,2017,57(11):1260-1265,6.基金项目
国家自然科学基金资助项目(61102090,61362010) （61102090,61362010）
