地基伪卫星多址干扰对测距的影响及改善方法  

Influence of MAI on Terrestrially-Based Pseudolites Ranging and Improving Method

作　　者：王振岭[1] 何成龙[1] 

机构地区：[1]中国电子科技集团公司第五十四研究所,河北石家庄050081

出　　处：《全球定位系统》2015年第2期12-16,共5页Gnss World of China

摘　　要：地基伪卫星是一类发送类似卫星导航信号的地基无线电导航增强设备,在独立组网工作模式下具有基于无源扩频测距信号实现局域高精度定位的能力。在接收机同时接收多颗伪卫星信号时,伪卫星信号间的多址干扰可导致伪卫星测距误差增大,进而影响定位精度。针对这一影响,分析了多址干扰对测距性能的影响及其特点,提出基于时分-码分多址(TD-CDMA)和串行干扰抵消(SIC)改善伪卫星多址干扰的方法,并对其性能及特点进行了分析、仿真和对比。仿真结果表明:基于TD-CDMA和SIC的方法可降低信号间的多址干扰,提高地基伪卫星测距精度。Terrestrially-based pseudolites is a onshore radio navigation system which has the similar signal to satellite navigation system.The independent pseudolites navigation network has the ability of local high-accuracy positioning by passive spread spectrum ranging signal.The MAI（Multiple Access Interference）of received pseudolites＇ signals might increase ranging error and then reduce positioning accuracy.A method of SIC（Serial Interference Cancellation）and TD-CDMA（Time division-Code division multiple access）for solving the problem was showed after analysis of MAI character,then showed the analysis,simulation and comparison of the methods.The simulation results showed that the method could reduce the MAI influence on ranging.

关 键 词：地基伪卫星 多址干扰 串行干扰抵消 TD-CDMA 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]