Single packet broadcasting (SPB) method applied in EPA Wireless for synchronization needs a plenty of time and packets and a long macro cycle. A probability-based synchronization (PBS) method was proposed to solve the problem. PBS allocates fewer opportunities for synchronization, in which all nodes send synchronization packets with equal probability. In theory, PBS needs less time and packets to keep nodes in synchronization with the gateway, and it can reduce the macro cycle of EPA Wireless. Besides, PBS is more energy saving and can reduce network flow. The performance of PBS does not decrease dominantly with the increasing nodenumber. PBS has a larger deviation than SPB but it does not affect the performance of EPA Wireless. Experiments were conducted on a real wireless network. The results showed the agreement of the experimental and theoretical performances.
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