Hardware in-the-Loop Demonstration of Real-Time Orbit Determination in High Earth Orbits

摘要

This paper presents results from a study conducted at Goddard Space Flight Center (GSFC) to assess the realtime orbit determination accuracy of GPS-based navigation in a number of different high Earth orbital regimes. Measurements collected from a GPS receiver (connected to a GPS radio frequency (RF) signal simulator) were processed in a navigation filter in real-time, and resulting errors in the estimated states were assessed. The study also makes direct comparisons between the results fromthe above hardware in-the-loop tests and results obtained by processing GPS measurements generated from software simulations. This provides a means to further validate the clock models, measurement noise parameters, and other error settings used insoftware simulations of orbit determination performance conducted at GSFC. High Earth orbits in the context of this paper are considered to be any orbit with apogee higher than 3000 km altitude, above which conventional space-capable GPS receivers may not be able to produce an instantaneous position and velocity solution.