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arXiv · 2109.05106

Minimizing AoI in Resource-Constrained Multi-Source Relaying Systems with Stochastic Arrivals

Abolfazl Zakeri·Mohammad Moltafet·Markus Leinonen·Marian Codreanu
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Abstract

We consider a multi-source relaying system where the sources independently and randomly generate status update packets which are sent to the destination with the aid of a bufferaided relay through unreliable links. We formulate a stochastic optimization problem aiming to minimize the sum average age of information (AAoI) of sources under per-slot transmission capacity constraints and a long-run average resource constraint. To solve the problem, we recast it as a constrained Markov decision process (CMDP) problem and adopt the Lagrangian method. We analyze the structure of an optimal policy for the resulting MDP problem that possesses a switching-type structure. We propose an algorithm that obtains a stationary deterministic near-optimal policy, establishing a benchmark for the system. Simulation results show the effectiveness of our algorithm compared to benchmark algorithms.

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Abolfazl Zakeri, Mohammad Moltafet, Markus Leinonen, Marian Codreanu. 2021-09-10. Minimizing AoI in Resource-Constrained Multi-Source Relaying Systems with Stochastic Arrivals. https://arxiv.org/abs/2109.05106

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