基于动态路径列表的无线传感器网络时间同步协议

Time synchronization protocol based on dynamic route list for wireless sensor network

为降低大规模无线传感器网络中时间同步误差的多跳累积,提出了一种基于动态路径列表的无线传感器网络时间同步协议(DRL-TSP)。该协议为每个节点保存一个待选同步动态路径列表,允许节点根据列表中的可用路径质量信息选择一条最适合当前同步要求的同步链路,从而最大程度地降低同步误差的多跳累积。将一种有效时间标识(TTA)技术用于同步机制中,使节点具备应对同步失败而导致链路失效的能力,保证同步过程的可靠性。实验结果表明:在平均可选上层链路为12条的情况下,DRL-TSP协议单跳同步误差为5.29μs;10跳同步误差被控制在11.10μs以下;因时标节点失效导致同步失败的节点比例远低于传感器网络同步协议(TPSN),接近洪泛时钟同步协议(FTSP)水平。提出的DRL-TSP协议在同步精度上优于现有的FTSP、TPSN等协议,且具有较高的鲁棒性。

To reduce the error accumulation of time synchronization in multihops for large-scale wire- less sensor networks, a Dynamic Route List based Time Synchronization Protocol （DRL-TSP） is pro- posed. The protocol uses an available synchronization route list in each node, and allows the node to choose an optimal synchronization route to reduce the error accumulation. An identification called TTA （Time to Available） is used to deal with the synchronization failure and to ensure the reliability of the synchronization process. Experimental results indicate that the synchronization error in single hop is 5.29 μs when the optionat upper links are 12 for each node, and the synchronization error is controlled under 11.10 μs within 10 hops. Moreover, the nodes of synchronization failure caused by time scale node invalidation are more low than that of Timing-sync Protocol for Sensor Network （TPSN） and close to that of Flooding Time Synchronization Protocol（FTSP）. Experimental results show that the proposed protocol has a better performance than the current protocols in precision and reliability.