针对无线传感器网络中随着节点数目增多,传统的参考广播同步算法网络开销非常大的问题,该文提出一种能量有效的参考广播同步算法。该算法首先只对不相邻的两个接收节点在多个参考广播消息的条件下求平均相位偏差,并且对计算得出的相位偏差进行最大后验估计;其次采用最小二乘线性回归方法周期性地拟合时钟偏移,完成同步过程。仿真结果表明,能量有效的参考广播同步算法在同步精度方面有所改进的同时,有效减少了无线传感器网络的能量消耗。
The traditional Reference Broadcast Synchronization (RBS) algorithm has a problem that network overhead is very large as the network nodes increase in Wireless sensor networks. An Energy-efficient RBS (ERRS) scheme is presented to work out the network overhead issue. Firstly, every receiving node, which is required to receive a couple of reference messages, computes mean phase offset to its nonadjacent receiving nodes, and estimates phase offset by maximum posteriori estimation; Secondly, the algorithm uses least-squares linear regression to fit clock skew periodically. The analysis on simulation result indicates that ERBS algorithm improve synchronization precision and reduce energy usage over l~R,q.