中文摘要：

信号多径效应是全球卫星定位系统（Global Positioning System,GPS）定位误差的主要来源之一。虽然差分技术可以提高导航系统的定位精度,但由于参考站和用户所处的地理环境不同,因此差分GPS系统仍然不能消除由于卫星信号多径所引起的定位误差。根据GPS多径信号模型的特点,本文提出了一种基于信号分离估计理论的GPS时延估计算法。该算法在信号时延未知情况下,先估计出信号的载波频率,然后根据估计得到频率,利用信号分离估计理论估计信号时延。仿真结果表明,该方法具有很好的估计精度,能够准确的估计出信号时延和频率,有效地抑制信号多径。当存在多径时,本文方法效果明显好于常规方法,并在大多数情况下优于常用的窄带相关算法。

英文摘要：

The effect of signal multipath is one of the main reason which lead to positioning error in Global Positioning System （GPS）.Although the differential technology can improve the positioning accuracy of the navigation system,but the reference stations and users being in different geographical environment,the differential GPS system still can＇t eliminate the positioning error caused by multipath signal.In the light of the character of GPS multipath signal model,this paper presents a GPS time delay estimation algorithm based on signal separation estimation theory.Firstly,frequency is estimated when the signal delay is unknown.Then,we use the estimated frequency to get signal delay information with signal separation estimation theory.It can be shown from the simulation results that the method with high estimation accuracy has a good time delay and frequency estimation performance and effectively mitigate the multipath. Comparing with the conventional method,new method has obviously advantages.It is even better than the narrow-band correlation algorithm in most cases.