Cycle-slip detection and reparation algorithm for satellite-ground two-way time difference measurements

High precision time-frequency reference requires high precision time-frequency transfer technology. The satellite-ground two-way time difference of carrier phase measurement can achieve higher time-frequency transfer accuracy. However, in the complex satellite-ground environments, due to the high flight dynamics of the spacecraft and the high transmission frequency of the time-frequency link, and the carrier doppler effect is large, gross errors and cycle slips are more likely to occur. This paper focuses on a carrier phase cycle slip detection and reparation algorithm for satellite-ground two-way time difference measurement system in high dynamic environment, and proposes a two-way cycle slip detection and reparation method for three-frequency mode. This method combined with Melbaurne wubbena (MW) combination method can realize the detection and repair of different types of cycle slips. For the three links, the existence of cycle slips can be detected and the mm-level cycle slip repair accuracy can be realized. The satellite-ground time synchronization performance of the satellite-ground two-way time difference measurement system based on carrier phase measurement is further analyzed. After cycle slip detection and repair, and link delay data processing, the time synchronization accuracy is better than 0.3×10^–12 s.