SYNCHRONIZATION CONTROL CAPABLE OF ESTABLISHING SYNCHRONIZATION WITHOUT TRANSMISSION OF DISTANCE INFORMATION BETWEEN CONTROL AND LOCAL EARTH STATIONS

摘要

In a TDMA satellite communication network comprising control and local earth stations communicable with one another through a satellite, a time difference between transmission and reception of a reference burst is measured at the control earth station to detect a time deviation (Tb) from a standard offset time (SO) predetermined for the control earth station. In the control earth station, the time deviation is doubled and added to the standard offset time to provide a reception time instant (t4) for the local earth station. Thus, the reception time instant is varied and predicted in the control earth station with reference to the time deviation detected in the control earth station. The local earth station determines a transmission time instant (t2 or t2') by delaying a reception timing signal by a predetermined time interval (Ta).