Mu Rongjun, Long Teng
School of Astronautics, Harbin Institute of Technology, Harbin 150001, China.
Sensors (Basel). 2021 Aug 20;21(16):5629. doi: 10.3390/s21165629.
For the tracking of high-dynamic satellite navigation signals, the conventional scalar tracking loop (STL) is vulnerable. Frequent signal-tracking interruption affects the continuity of navigation. The vector tracking loop (VTL) can overcome this disadvantage. However, there are some difficulties in implementing existing vector tracking methods on a real-time hardware receiver, such as the synchronization problem and computation load. This paper proposes an implementation framework of VTL based on a partial open-loop numerically controlled oscillator (NCO) control mode that can be implemented with minor modifications on an existing receiver platform. The structure of VTL, the design of the navigation filter, and the key points of hardware implementation are introduced in detail. Lastly, the VTL performance was verified by a GPS simulator test. The results show that the proposed VTL can run in real-time and be significantly improved in the tracking continuity of high-dynamic signals, tracking sensitivity, positioning accuracy, and recovery time for interrupted signals compared with those of STL.
对于高动态卫星导航信号的跟踪,传统的标量跟踪环(STL)较为脆弱。频繁的信号跟踪中断会影响导航的连续性。矢量跟踪环(VTL)可以克服这一缺点。然而,在实时硬件接收机上实现现有的矢量跟踪方法存在一些困难,如同步问题和计算负载。本文提出了一种基于部分开环数控振荡器(NCO)控制模式的VTL实现框架,该框架可以在现有接收机平台上进行少量修改后实现。详细介绍了VTL的结构、导航滤波器的设计以及硬件实现的关键点。最后,通过GPS模拟器测试验证了VTL的性能。结果表明,与STL相比,所提出的VTL能够实时运行,并且在高动态信号的跟踪连续性、跟踪灵敏度、定位精度以及中断信号的恢复时间方面有显著提高。