Navigation in GNSS-Denied Environment Based on Observation of RSOs and Stars

Navigating in an environment, where Global Navigation Satellite System (GNSS) signals are unavailable, presents a formidable challenge. A feasible strategy involves integrating stellar observations with inertial information to realize precise navigation. Inertial/Stellar Celestial Navigation enhances position accuracy by addressing gyro drift through stellar observations. However, the position error still continues to grow over time which arises from unobservable error factors. With improved orbit determination accuracy and the resident space object (RSO) observation method, navigating using RSO observation is gaining viability. This study models the RSO navigation problem as a Perspective-n-Point (PnP) problem and proposes that observing more than 6 RSOs can yield complete solution for position and attitude. Additionally, a tightly coupled navigation algorithm integrating inertial, stellar, and RSO observations is introduced. Simulation validation under dynamic condition demonstrates the algorithm’s efficacy, achieving a position accuracy of 30[Formula: see text]m and an attitude accuracy of 5[Formula: see text]arcsec (RMS) without GNSS data.