A communication protocol of man overboard system based on BeiDou

Through a proper design of management of communication process and sequence control, this novel communication protocol of MOB system meets the general operational requirements proposed by draft MOB recommendation. This protocol supports active alarm. Also, with the polling mode used in this protocol, the MOB system is inherently fail-safe because it activates when a signal is not detected. By the mechanism of retransmission and error check, this protocol can lower the rate of false alarm and enhance the reliability during the communication process. In addition, by bringing in the repeaters, this protocol also solve the problem of expanding the coverage of the base station.