Design of an Ultra-Tightly Coupled Integrated INS/GPS Navigation System Based on UPF

For the strong nonlinearity of ultra-tightly coupled INS/GPS navigation system, this paper present to use the unscented particle filter (UPF) for integration system. The nonlinear measurement equation can be constructed by including the second-order term in the Taylor series of the pseudorange measurements. At the same time, the UPF algorithm is simplified, which greatly reduces the computational complexity caused by a large number of UT transformations. The experimental results indicated that the UPF-based ultra-tight INS/GPS integration system can effectively overcome the nonlinear error, and has higher signal tracking performance and navigation performance in highly dynamic and strong interference environments.