摘要
Abstract
The global navigation satellite system( GNSS) can not provide Position,Velocity,and Time( PVT) service accurately,safely and reliably due to interference and multipath. For this problem,the significance of developing a GNSS interference and multipath monitoring system is analyzed,followed by the introduction to the currently used interference and multipath detection methods. As the main content, the design and implementation of a GNSS interference and multipath monitoring system is introduced,which is able to mo-nitor interference and multipath signals in the bands of navigation signals of current four major GNSS sys-tems( i. e. ,GPS,GLONASS,Galileo,and BDS) ,as well as nearby frequency bands. The system based on software-defined radio( SDR) has preferable flexibility and extensibility by using modular design. Accord-ing to the characteristics of different interferences,the detection algorithms are improved in terms of the de-mand for actual application. Firstly,the principle of energy threshold detection is adopted for the suppres-sion jamming,and corresponding methods are designed for interference with different forms. Secondly,the multi-correlation peaks detection algorithm based on acquisition is used to check the existence of deception jamming signal. Thirdly,the Multipath Estimate Delay Lock Loop( MEDLL) technique,which is based on the Maximum-Likelihood criterion,is adopted to estimate the parameters of the multipath effects. The ex-perimental results show that the system can detect the existence of various kinds of interference and mul-tipath signals. The characteristic parameters of those signals can be extracted and then provided to the us-ers to facilitate the localization,elimination and avoidance of the interference sources,as well as the sup-pression of the multipath signals.关键词
全球导航卫星系统/干扰监测/多径监测/软件无线电Key words
global navigation satellite system( GNSS)/interference monitoring/multipath monitoring/soft-ware-defined radio( SDR)分类
信息技术与安全科学
