Dual time synchronisation method for wireless sensor networks

Abstract

Time synchronisation plays an important role in time division multiple access (TDMA) wireless sensor networks (WSNs). Existing time synchronisation methods suffer from cumulative time error and the imbalance of time synchronisation precision, and those factors bring fluctuations to nodes’ time and will become worse with the increase of hops, inducing more unstable communication links for sensor nodes. A dual time synchronisation method (DTSM) for WSNs is introduced, which is endowed with the maintenance of two running time sources per node, one for its parent and the other for its sons. This method eliminates the time fluctuations among nodes especially for the nodes with greater hops, so as to obtain more stable links for large-scale networks. This method is implemented on the SCSC-RFA1 platform and the results show its validity.