Keeping sensor data fresh is desired for Industrial Internet of Things (IIoT), especially, in real-time monitoring applications. However, this may require sensors always in active mode and, thus, incur low energy efficiency. In this article, we consider that a wireless sensor monitors a dynamical system and reports real-time measurements to a processing center through an unreliable wireless channel. We study the problem of optimizing the sensor data freshness in terms of Age of Information (AoI) while saving energy by scheduling the sensor to sleep when needed. The problem is formulated as a Markov decision process that takes both AoI and energy consumption into account, to which we theoretically prove that the optimal scheduling policy forms a cyclic sleep–wake pattern. The optimal sleep period is also analyzed. Simulation results demonstrate that the proposed scheduling policy outperforms other existing policies.

中文翻译：

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工业物联网中节能 AoI 优化的最佳睡眠调度


工业物联网 (IIoT) 需要保持传感器数据最新，尤其是在实时监控应用中。然而，这可能需要传感器始终处于活动模式，因此会导致能源效率较低。在本文中，我们考虑无线传感器监视动态系统并通过不可靠的无线通道向处理中心报告实时测量结果。我们研究了根据信息时代（AoI）优化传感器数据新鲜度的问题，同时通过在需要时安排传感器进入睡眠状态来节省能源。该问题被表述为同时考虑 AoI 和能量消耗的马尔可夫决策过程，我们从理论上证明了最优调度策略形成了循环睡眠-觉醒模式。还分析了最佳睡眠时间。仿真结果表明，所提出的调度策略优于其他现有策略。