面向北斗B1信号利用阵列天线抑制极近多径的算法研究

项目名称： 面向北斗B1信号利用阵列天线抑制极近多径的算法研究

项目编号： No.61304225

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 自动化技术、计算机技术

项目作者： 陈新

作者单位： 上海交通大学

项目金额： 23万元

中文摘要： GNSS接收机技术经过过去近三十年的发展已经得到了长足的进步，在定位精度、跟踪灵敏度、首次定位时间以及功耗等方面得到了极大地提高，但是多径信号干扰却一直是困扰GNSS接收机定位精度的一个主要问题。尤其是对于延迟小于100纳秒的近多径信号目前还没有很好的抑制方法。本课题面向北斗B1信号，根据卫星直达信号和多径信号的入射角不同的特点，结合信号入射角快速估计iMLE算法和矢量信号空间投影技术，提出利用天线阵列信号处理技术在多径信号入射方向形成增益零点而卫星直达信号入射方向增益不变，从而抑制延迟小于100纳秒以内的近多径信号。和目前国内外同类算法相比对近多径误差抑制能力预计提高50%以上。本课题的天线阵列算法也能够和其他多径抑制算法结合，有效抑制近、中、远各级多径，大幅提高接收机的定位精度。

中文关键词： 多径抑制；阵列信号处理；信号入射角估计；空间矢量投影；高精度定位

英文摘要： Over the past decades GNSS receiver technologies have got remarkable developments. The performance on positioning accuracy, tracking sensitivity, first fix time and power consumption, etc., is greatly enhanced. However the multipath-induced error is still a major error source for GNSS receiver and has not obtained properly resolved yet, especially for those delayed less than 100 nanosecond with respect to the line-of-sight signal. Stemming from Beidou B1 signal and based on the characteristics that the angle-of-arrival of multipath signal is different than that of line-of-sight signal, this proposal suggests using antenna array signal processing technology as well as signal angle-of-arrival fast estimation iMLE algorithm and vector signal space projection technique, in order to mitigate the multipath errors within 100 nanosecond by forming the null on multipath direction whereas the gain on line-of-sight direction. It is expected that this algorithm can improve the performance of mitigating near-in multipath error by more than 50% with respect to the current multipath mitigation methods. It can also be combined with other mitigation methods to simultaneously mitigation near, middle and far multipath signals, significantly enhancing the receiver's positioning accuracy.

英文关键词： multipath mitigation；array signal process；DOA estimation；subspace vector projection；highly precise positioning