This paper considers a multi-source real-time updating system in which an energy harvesting (EH)-powered transmitter node has multiple sources generating status updates about several physical processes. The status updates are then sent to a destination node where the freshness of each status update is measured in terms of Age of Information (AoI). The status updates of each source and harvested energy packets are assumed to arrive at the transmitter according to independent Poisson processes, and the service time of each status update is assumed to be exponentially distributed. Unlike most of the existing queueing-theoretic analyses of AoI that focus on characterizing its average when the transmitter has a reliable energy source and is hence not powered by EH (referred henceforth as a non-EH transmitter), our analysis is focused on understanding the distributional properties of AoI in multi-source systems through the characterization of its moment generating function (MGF). In particular, we use the stochastic hybrid systems (SHS) framework to derive closed-form expressions of the average/MGF of AoI under several queueing disciplines at the transmitter, including non-preemptive and source-agnostic/source-aware preemptive in service strategies. The generality of our results is demonstrated by recovering several existing results as special cases.

中文翻译：

---

由能量收集驱动的多源更新系统中的信息时代

本文考虑了一个多源实时更新系统，其中能量收集 (EH) 供电的发射器节点具有多个源，可生成有关多个物理过程的状态更新。然后将状态更新发送到目标节点，在那里根据信息年龄 (AoI) 来衡量每个状态更新的新鲜度。假设每个源和收集的能量包的状态更新根据独立的泊松过程到达发射机，并且假设每个状态更新的服务时间呈指数分布。与大多数现有的 AoI 排队理论分析不同，这些分析侧重于在发射器具有可靠能源且因此不由 EH 供电（以下称为非 EH 发射器）时表征其平均值，我们的分析侧重于通过其矩生成函数 (MGF) 的表征来了解多源系统中 AoI 的分布特性。特别是，我们使用随机混合系统 (SHS) 框架在发射器的几个排队规则下推导出 AoI 的平均值/MGF 的封闭形式表达式，包括服务策略中的非抢占式和源不可知/源感知抢占式. 通过将几个现有结果恢复为特殊情况，证明了我们结果的普遍性。我们使用随机混合系统 (SHS) 框架来推导出 AoI 的平均/MGF 在发射器的几个排队规则下的封闭形式表达式，包括服务策略中的非抢占式和源不可知/源感知抢占式。通过将几个现有结果恢复为特殊情况，证明了我们结果的普遍性。我们使用随机混合系统 (SHS) 框架来推导出 AoI 的平均/MGF 在发射器的几个排队规则下的封闭形式表达式，包括服务策略中的非抢占式和源不可知/源感知抢占式。通过将几个现有结果恢复为特殊情况，证明了我们结果的普遍性。