关键词: PPP/INS, 组合导航, 电离层闪烁, 精密单点定位, 惯性导航

Abstract:

Ionospheric scintillations in low latitude and polar regions can introduce random interference in GNSS signals， deteriorating the conventional PPP performance with the unmodelled ionospheric scattering residual. The short-term high accuracy and interference-free INS can assist PPP to form PPP/INS integrated navigation system， improving the navigation performance in the sophisticated environment. However， the mechanism and performance of INS assisting PPP with scintillations requires further research. Thus， starting with the model and estimation process， impacts of ionospheric scintillation on the data processing of PPP/INS tightly and loosely coupled systems is analyzed. Then， we apply scintillation-impacted GPS data from 2 stations in Hong Kong and simulated INS data to validate the PPP/INS performance. Theoretical analysis and experiments indicate the superiority of the tightly coupled system in the ionospheric scintillation environment.. During the experiment， the tightly coupled system improves 56.6% and 34.0% horizontal and vertical positioning accuracy， respectively； 77.5% and 79.5% horizontal and vertical velocity accuracy， respectively； 85.6%， 49.6% and 88.9% pitch， roll and yaw accuracy， respectively as compared with the loosely coupled system.

Key words: PPP/INS, integrated navigation, ionospheric scintillation, precise point positioning, inertial navigation systems