基于WIA-PA传感器网络的能量有效时间同步算法

An Energy-Efficient Algorithm for Time Synchronization Based on WIA-PA Sensor Networds

摘要:

WIA-PA协议是一种新型工业级无线传感器网络国际标准；当WIA-PA网络内节点数目增多时,传统的参考广播同步算法RBS以及改进型ERBS算法网络开销非常大；针对这一严峻的问题,提出了一种能量有效的局部最优时间同步算法；该算法对相邻的接收节点在多个参考广播消息的条件下求取平均相位偏差,然后对此平均相位偏差进行最大后验估计,最后根据此估计值调整本地时钟；仿真结果表明,所提时间同步算法在同步精度方面比RBS约提高168%,比ERBS约提高24%；同时,同步过程中的网络能耗也大大减少。

Abstract:

WIA-PA protocol is a new type of international communication standards for industrial wireless sensor networks. With the incensement of the number of the sensor nodes in the WIA-PA network, the overhead and the energy consumption of the whole network appear to be very large based on the traditional reference broadcast synchronization algorithm RBS and its modified version algorithm ERBS. In order to solve this serious problem, this paper puts forward a kind of energy efficient local optimal algorithm for the time synchronization process. The algorithm solves out the average phase deviation according to the adjacent receiving node under the condition of multiple reference broadcast messages, and then carries out maximum posteriori estimation for this calculated phase deviation, and finally adjusts the local clock according to the estimate. The simulation results show that the synchronous accuracy of the proposed time synchronization algorithm is about 168% higher than that of RBS and is about 24% higher than that of ERBS. At the same time, the energy consumption in the process of time synchronization is also greatly reduced。