In a TDMA satellite communication system, one of the stations is elected the primary station which transmits a reference burst, known as the frame reference burst (FRB), to all other stations at the beginning of every transmission frame, to synchronize the local clocks in each station and to transmit station channel assignments and other control information. Each subsidiary station, in turn, responds to the FRB by transmitting a transmit reference burst (XRB) once every superframe, a superframe is 20 frames long, each XRB containing its station's request for additional channel assignments and other control information.
In order to assure that the synchronous operation of the network will continue when the reference station experiences a failure, the prior art has provided an alternate reference station which is designated in the network, and which will assume the role of the primary reference station in the event that the existing primary reference station must abdicate its primary reference role. The operation of transferring control from the primary reference station to the alternate reference station has been called baton passing. Prior art baton passing techniques have employed a relatively coarse criterion of a total absence of acknowledgements from other stations in the network as an indication that they have not received the FRBs from the primary reference station.
However, as TDMA satellite communication systems have become more sophisticated, providing greater function at higher speeds, a more refined baton passing technique is required since the prior art baton passing technique would allow the reference station to meet the prior art criterion for good health and yet still be sending bursts of information having a high channel error rate. Since the reference station also generally serves the function of making channel assignments for all of the subsidiary stations based upon a capacity request in the XRB, it would consequently be assigning the wrong channel allocations if the reference reads the XRB incorrectly which could create chaotic results in the TDMA system.