一种用于高动态全球定位系统信号跟踪的新模型

A Novel Model for High Dynamic GPS Signal Tracking

针对传统全球定位系统(GPS)信号跟踪方法在高动态环境下跟踪精度不够理想且容易失锁等缺陷,提出了一种新的跟踪模型.采用包含多普勒频移与码相位误差的二维观测相关器组,并通过基于列文伯格-马夸尔特方法优化的迭代扩展卡尔曼滤波算法,使跟踪环路在码相位与载波频率初始捕获误差较大的情况下,依然能够快速而准确地收敛,成功解调出导航信息.仿真结果显示,利用新的GPS信号跟踪模型能够高质量地完成加速度为150g的高动态GPS信号跟踪.

A novel tracking model was proposed for high dynamic condition under which the traditional GPS signal tracking method has a high probability of losing lock as well as a low accuracy. The output from a large number of eorrelators with wide ranges of uncertainty in code phase and carrier phase were used. An optimized iterated extended Kalman filter algorithm based on the Levenberg-Marquardt method was also implemented to process the output from the correlators, despite large acquisition errors. The simulation results show that the new model performs well in tracking a high dynamic GPS signal with an acceleration of 150 g.