Elsharief Mahmoud, El-Gawad Mohamed A Abd, Ko Haneul, Pack Sangheon
School of Electrical Engineering, Korea University, Seoul 02841, Korea.
Department of Computer Convergence Software, Korea University, Sejong 30019, Korea.
Sensors (Basel). 2020 Jul 23;20(15):4095. doi: 10.3390/s20154095.
Time synchronization is an essential issue in industrial wireless sensor networks (IWSNs). It assists perfect coordinated communications among the sensor nodes to preserve battery power. Generally, time synchronization in IWSNs has two major aspects of energy consumption and accuracy. In the literature, the energy consumption has not received much attention in contrast to the accuracy. In this paper, focusing on the energy consumption aspect, we introduce an energy-efficient reference node selection (EERS) algorithm for time synchronization in IWSNs. It selects and schedules a minimal sequence of connected reference nodes that are responsible for spreading timing messages. EERS achieves energy consumption synchronization by reducing the number of transmitted messages among the sensor nodes. To evaluate the performance of EERS, we conducted extensive experiments with Arduino Nano RF sensors and revealed that EERS achieves considerably fewer messages than previous techniques, robust time synchronization (R-Sync), fast scheduling and accurate drift compensation for time synchronization (FADS), and low power scheduling for time synchronization protocols (LPSS). In addition, simulation results for a large sensor network of 450 nodes demonstrate that EERS reduces the whole number of transmitted messages by 52%, 30%, and 13% compared to R-Sync, FADS, and LPSS, respectively.
时间同步是工业无线传感器网络（IWSN）中的一个重要问题。它有助于传感器节点之间实现完美的协调通信，以节省电池电量。一般来说，IWSN中的时间同步有能耗和精度两个主要方面。在文献中，与精度相比，能耗并未受到太多关注。在本文中，我们聚焦于能耗方面，为IWSN中的时间同步引入了一种节能参考节点选择（EERS）算法。它选择并调度一个负责传播定时消息的最小连接参考节点序列。EERS通过减少传感器节点之间的传输消息数量来实现能耗同步。为了评估EERS的性能，我们使用Arduino Nano RF传感器进行了广泛的实验，结果表明EERS传输的消息数量比之前的技术（稳健时间同步（R-Sync）、时间同步快速调度与精确漂移补偿（FADS）以及时间同步协议的低功耗调度（LPSS））要少得多。此外，对一个包含450个节点的大型传感器网络的仿真结果表明，与R-Sync、FADS和LPSS相比，EERS分别将传输消息的总数减少了52%、30%和13%。
