School of Advanced Technology, Xi'an Jiaotong-Liverpool University (XJTLU), Suzhou 215123, China.
Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3BX, UK.
Sensors (Basel). 2022 Jul 14;22(14):5276. doi: 10.3390/s22145276.
In a wireless sensor network (WSN), reducing the energy consumption of battery-powered sensor nodes is key to extending their operating duration before battery replacement is required. Message bundling can save on the energy consumption of sensor nodes by reducing the number of message transmissions. However, bundling a large number of messages could increase not only the end-to-end delays and message transmission intervals, but also the packet error rate (PER). End-to-end delays are critical in delay-sensitive applications, such as factory monitoring and disaster prevention. Message transmission intervals affect time synchronization accuracy when bundling includes synchronization messages, while an increased PER results in more message retransmissions and, thereby, consumes more energy. To address these issues, this paper proposes an optimal message bundling scheme based on an objective function for the total energy consumption of a WSN, which also takes into account the effects of packet retransmissions and, thereby, strikes the optimal balance between the number of bundled messages and the number of retransmissions given a link quality. The proposed optimal bundling is formulated as an integer nonlinear programming problem and solved using a self-adaptive global-best harmony search (SGHS) algorithm. The experimental results, based on the Cooja emulator of Contiki-NG, demonstrate that the proposed optimal bundling scheme saves up to 51.8% and 8.8% of the total energy consumption with respect to the baseline of no bundling and the state-of-the-art integer linear programming model, respectively.
在无线传感器网络（WSN）中，降低电池供电的传感器节点的能耗对于延长其在需要更换电池之前的运行时间至关重要。消息捆绑可以通过减少消息传输的数量来节省传感器节点的能耗。然而，捆绑大量消息不仅会增加端到端延迟和消息传输间隔，还会增加分组错误率（PER）。端到端延迟在延迟敏感型应用中至关重要，例如工厂监控和灾害预防。当捆绑包括同步消息时，消息传输间隔会影响时间同步精度，而增加的 PER 会导致更多的消息重传，从而消耗更多的能量。为了解决这些问题，本文提出了一种基于 WSN 总能耗的目标函数的最优消息捆绑方案，该方案还考虑了分组重传的影响，从而在给定链路质量的情况下，在捆绑消息的数量和重传数量之间取得最佳平衡。所提出的最优捆绑被制定为一个整数非线性规划问题，并使用自适应全局最佳和声搜索（SGHS）算法来解决。基于 Contiki-NG 的 Cooja 模拟器的实验结果表明，所提出的最优捆绑方案分别比不捆绑和最先进的整数线性规划模型的基线节省了高达 51.8%和 8.8%的总能耗。
