An Onboard Ultra-Rapid Orbit Determination Strategy for LEO Satellite Utilizing GNSS Data

Real-time data processing onboard is increasingly essential for future Low Earth Orbit (LEO) satellites. We propose an ultra-rapid onboard orbit determination (OD) strategy that achieves decimeter-level accuracy, potentially up to centimeter-level. This approach enables high-precision OD and prediction using either precise GNSS products from ground stations or broadcast ephemeris. Consequently, it allows satellite payloads to deliver real-time, high-performance services to ground users, with significant potential for various applications. Experimental results show that using IGS final GNSS products, this method achieves 5 cm accuracy for OD and better than 10 cm for 10-min orbit prediction. With broadcast ephemeris, the accuracies are better than 45 cm for OD and 1 m for 10-min orbit prediction.