互相关干扰下的GNSS弱信号检测算法  

Detection of GNSS Weak Signal in Cross Correlation Interference

作　　者：何文涛[1] 徐建华[1,2] 叶甜春[1] 

机构地区：[1]中国科学院微电子研究所,北京100029 [2]杭州中科微电子有限公司,浙江杭州310053

出　　处：《电子学报》2011年第2期471-475,共5页Acta Electronica Sinica

基　　金：国家863高技术研究发展计划(No.2007AA12Z344)

摘　　要：GNSS接收机在室内等环境中的应用要求接收机具有接收弱信号的能力.在检测弱信号时,接收机可能由于受到强信号的互相关干扰而错误的捕获或跟踪到强信号的互相关峰.本文采用相干和非相干积分组合的方法来提高灵敏度.同时,通过估计强信号的互相关干扰功率,自动调整检测门限来抑制互相关干扰.仿真结果说明,采用20ms的相干积分和1s的非相干积分,在没有互相关干扰的情况下,可以接收-160dBm的弱信号;在互相关干扰增强的情况下,检测门限自动提高,使得虚警概率保持在预设值以下.GNSS receivers are required to be capable of receiving weak signals to satisfy indoor Applications.When detecting weak signals,the receiver may falsely acquire or track the cross correlation peaks of strong signals due to the cross correlation interference.Coherent and non-coherent integration are combined to improve the reception sensitivity.Meanwhile,the detection threshold is adjusted automatically by estimating the cross correlation interference power from strong signals to mitigating cross correlation interference.Simulation results show that the receiver can detect weak signal of-160dBm for 20ms coherent and 1s non-coherent integration without the interference of cross correlation.As the power of cross correlation interference increases,the resultant false alarm probability is maintained below the present value by automatically increasing the detection threshold.

关 键 词：GNSS接收机 弱信号 高灵敏度 互相关干扰 

分 类 号：TN96[电子电信—信号与信息处理]