| 摘要 |
The invention relates to a method and device for synchronisation of one or more distant clocks (2) to a central clock (1) by means of a bi-directional satellite radio frequency link (9.1, 9.2). Suitable radio signal transmitters (8, 12) and receivers (5, 1) at both sides of the link exchange timing and data signals. From the time-difference measurements (6, 14) performed at both sides, a control signal is derived to adjust the distant clock, which is directly built into the remote ground station equipment (11), to be in synchronism with respect to time and frequency to the central clock by means of the Two-Way Satellite Time and Frequency Transfer (TWSTFT) method. The user has access to timing signals (18) which directly represent the time of the central clock (1). For data transmission, the same signals are used which are already used for the timing measurements. Hence, a system operating in real-time is established which makes available the information about the control-loop error (15, 16) at both sides of the system. |
