摘要： 针对全球定位系统软件接收机在高动态环境下跟踪精度低与容易失锁的问题,提出一种基于最大似然估计的高精度快速跟踪方法。分析最大似然估计高动态跟踪环路结构的设计过程,给出基于两步逼近方法的最大似然估计方法,得到伪码相位误差估计值,并采用插值法获得更高的多普勒频率误差估计精度。理论分析与仿真结果表明,与传统的最大似然估计方法相比,改进最大似然估计方法的耗时减少27.3%,且具有更高的跟踪精度。

关键词: 最大似然估计, 全球定位系统软件接收机, 高动态, 信号跟踪, 两步逼近方法, 插值法

Abstract: In high dynamic environment,the Global Positioning System(GPS) software receiver has low tracking accuracy and is prone to loss of lock.To solve these problems,a high accuracy and fast tracking method based on Maximum Likelihood Estimation(MLE) is proposed.The design process of the high dynamic tracking loop structure based on MLE is analyzed,and the maximum likelihood estimation method based on two-step approximation is proposed,which can quickly acquire the code phase error estimation value.The interpolation method is used to get higher accuracy of the Doppler frequency error estimation.Theoretical analysis and simulation results show that compared with the traditional maximum likelihood estimation method,the improved maximum likelihood estimation method reduces the time consumption by 27.3%,and has higher tracking accuracy.

Key words: Maximum Likelihood Estimation(MLE), Global Positioning System(GPS) software receiver, high dynamic, signal tracking, two-step approximation method, interpolation method

中图分类号: 

• TP391