Adaptively Precise Time Synchronization Technique for Inter-Satellite Link Equipment of Navigation Satellite

The clock synchronization precision between the inter-satellite link equipment local time and the satellite atomic clock has an impact on the orbit determination and time synchronization in navigation satellites Constellation. A precise synchronization method for the ISL equipment is proposed in this paper. The integral second count of the local time is determined by the 1PPS; and the decimal fraction is calculated from the reference clock signal phase. For solving the integer ambiguity problem in the local time, the adaptive ambiguity resolution is presented. Experimental results show that this method is immune to the phase difference between the working clock and the 1PPS, and adapts to the initial phase inconformity caused by the various cable length between the reference clock signal and the 1PPS. The precision of time synchronization is better than 0.05ns.