A research on high-precision time-synchronization and ranging system between satellites

The paper describes a time-synchronization and ranging system for interferometry in distributed satellites. Both time-synchronization and ranging are accomplished in one circuit which provides high-precision and real time capabilities. The method of two way time transfer (TWTT) is applied in the synchronization of satellites. The distance measurement is derived from the lagging phase of dual-frequency carriers which is caused by transmitting path between satellites, and the integer ambiguity with module 2pi is resolved by the PN code. In this system which the paper described, the precision of time-synchronization can reach and order of nanosecond, at the same time, and the precision of ranging is less than 1cm.