Abstract:Aiming at the problem that the current GPS real-time clock bias determination algorithm is based on real-time observation data stream, which limits the reliability and integrity of the product to the network quality, and that the accuracy of broadcast ephemeris and IGU-P is low, we propose and implement a real-time clock bias determination algorithm based on the connection of hourly observation files. The algorithm is realized based on hourly observation files data. By combining clock bias estimation with adaptive ultra-short-term clock bias prediction, the real-time clock bias is determined. 30 days online result shows that, STD of GPS real-time clocks generated by the connection method is 0.25 ns, equal to IGS RTS, much higher than STD of broadcast ephemeris and IGU-P. Furthermore, this method can improve the reliability and integrity of GPS real-time clocks.