信号级GNSS/SINS超紧组合导航仿真平台设计

超紧组合是全球卫星导航系统(global navigation satellite system, GNSS)和捷联惯性导航系统(strapdown inertial navigation system, SINS)组合中最深层次的信息融合方式。由于需要重新设计GNSS接收机内部的捕获跟踪环路以接收SINS的辅助信息, 超紧组合的工程实现较为困难。从信号级层次出发研究超紧组合的难点在于得到同源且同步的GNSS和SINS信号, 并打开GNSS接收机的捕获跟踪环路。为此, 构建了信号级GNSS/SINS超紧组合仿真平台, 分别设计了载体轨迹发生器、GNSS中频信号发生器、惯导解算器、GNSS软件接收机、组合导航滤波器等关键环节, 从而攻克了上述技术难关。该仿真平台不仅验证了超紧组合在高动态应用方面的优越性, 同时也为其迈向实际应用奠定了坚实的基础。

Design of ultra-tightly integrated GNSS/SINS simulation platform in signal level

The ultra-tight integration is the deepest information fusion mode in the integrations of global navigation satellite system (GNSS) and strapdown inertial navigation system (SINS). The acquisition and tracking loops in a GNSS receiver must be redesigned to obtain the SINS aiding signal, so the industrial implementation of the ultra-tight integration is very difficult.The difficulties of studying the ultra-tight integration in the signal level lie in sampling the homologous and synchronous GNSS and SINS signals and opening the GNSS receiver's acquisition and tracking loops. Therefore, this paper constructs an ultra-tightly integrated GNSS/SINS simulation platform in the signal level to overcome the difficulties above. The platform is composed of a vehicle trajectory generator, a GNSS intermediate frequency signal generator, an inertial navigation solver, a GNSS software receiver, and an integrated navigation filter, etc. The platform can not only verify the superiority of the ultra-tight integration in high dynamics, but also lay a solid foundation for its applications.