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arXiv · 2206.05710

Age of Information: A Two-Sensor Status Update System Monitoring The Same Process

Tianqing Yang·Zhengchuan Chen·Howard H. Yang·Min Wang·Yunjian Jia·Tony Q. S. Quek
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Abstract

This work studies the average age of information (AoI) of a monitoring system in which two sensors are sensing the same physical process and update status to a common monitor using their dedicated channels. Generally, using redundant devices to update the status of a process can improve the information timeliness at the monitor, but the disordered arrivals of updates also make the AoI analysis challenging. To that end, we model the system as two M/M/1/1 parallel status updating queues. By leveraging tools from stochastic hybrid system (SHS), we provide a general approach to analyze the average AoI, whereas a closed-form expression can be obtained when the status arrival rates and/or the service rates are the same for the two sensors. Numerical results validate the correctness of the theoretical analysis.

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Tianqing Yang, Zhengchuan Chen, Howard H. Yang, Min Wang, Yunjian Jia, Tony Q. S. Quek. 2022-06-12. Age of Information: A Two-Sensor Status Update System Monitoring The Same Process. https://arxiv.org/abs/2206.05710

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