Patent ID: 8488518

Claim:
A system for synchronising stations in a wireless communications network comprising: at least one airborne or space-based vehicle; and at least two stations, each station having receiver means in data communication with the at least one airborne or space-based vehicle and control means in data communication with the receiver means and in control communication with a communication means, wherein, when each receiver means receives a synchronisation signal from the at least one airborne or space-based vehicle: each receiver means forwards the synchronisation signal to its respective control means; each control means processes the synchronisation signal to determine an operational frequency required by its respective communication means to maintain or establish communication with the other station; and each control means controls its respective communication means to change to the determined operational frequency, the system being characterized in that each station also has a real-time clock for emitting a time pulse, the clock being coupled to the control means of the station, the synchronisation signal comprising a time and position sentence, the control means parses the sentence to determine a time of a timing pulse that immediately precedes the sentence, and in that a rising edge of the timing pulse is used to synchronise the clock.