Highly precise time synchronization protocol for ZigBee networks

Time synchronization is a critical middleware service of distributed system. In particular, wireless sensor networks is a distributed system which makes extensive use of synchronized time in many contexts (e.g. for data fusion, TDMA schedules, synchronized sleep periods, etc.). In addition, synchronization precision has become a critical area of research today. Time synchronization with very high precision is needed at some special application. In this paper, we proposed a high degree of accuracy time synchronization Protocol-Physical Layer Integrated Synchronization Protocol (PLISP). Different from adding timestamp in MAC layer of traditional time synchronization protocol, we advocate a novel way to add timestamp. We add timestamp in physical layer which can utmost reduce influence of nondeterminacy factor to synchronization precision. We get time synchronization precision is less than 1 &mus in experiments. Result shows that this method is feasible and can be used to wireless sensor networks.