基于扩展卡尔曼滤波的全球导航卫星系统矢量跟踪建模与仿真

针对现有公开资料缺乏对全球导航卫星系统（GNSS）矢量跟踪算法具体滤波跟踪控制过程的详细分析，建立了矢量延迟/频率锁定环（VDFLL）跟踪模型并对模型线性化过程进行推导。重点分析了矢量VDFLL跟踪算法时序逻辑控制问题，同时针对VDFLL无法实现对载波相位锁定等问题，提出了一种串联式锁相环（PLL）电文解调模型。建立了以软件接收机为平台的矢量VDFLL模型，并进行了半实物仿真验证。仿真结果表明，所建矢量VDFLL控制模型不仅正确地实现对接收机状态信息的最优估计，同时具有良好的动态跟踪性能。

Modeling and Simulation on GNSS Vector Tracking Loop Based on Extended Kalman Filter

Considering a limited public information about analysis of GNSS vector tracking algorithm control process, a vector delay/frequency lock loop (VDFLL) tracking model is established, and a derivation on the model’s linearization process is proposed.The sequential control logic of vector tracking algorithmis analyzed. For the fact that VDFLL cannot lock the carrier phase, a message demodulation mode based on series phase-locked loop (PLL) is put forward. And a vector VDFLL model is implemented on the platform of a software receiver. The simulation results indicate that the controlling model not only can output correct and optimal estimate for receiver state information, but also has an excellentdynamic tracking performance.