High precision over-the-horizon time transfer by a 40.5km tropospheric link

High precision time synchronization is of vital importance for the distributed system’s normal operation. One way troposphere time transfer (OWT3) is one of implemented means to achieve high precision over-the-horizon time synchronization. In this paper, we put forth OWT3 to achieve the system’s time synchronization and operated an outfield experiment. Firstly, the construction of OWT3 has been established. Then we studied troposcatter channel’s influences on OWT3 theoretically. Besides, an outfield experiment was carried out over a 40.5km tropospheric link between Xi’an and Sanyuan. From the experiment, we could conclude that OWT3 is a feasible time synchronization means for distributed system. Normal demodulation condition of OWT3 is that the signal power after down-conversion is 20 dBm around. And troposcatter channel’s influences on OWT3 system are about 37.0 + 25.8 ns during 5000 samples (about 1.38h) roughly.