Age-of-Information-based Scheduling in Multiuser Uplinks with Stochastic Arrivals: A POMDP Approach

TL;DR

This paper addresses multiuser uplink scheduling to minimize age of information using a POMDP framework, proposing an optimal and a low-complexity myopic policy with near-optimal performance.

Contribution

It formulates the AoI minimization as a POMDP and develops a dynamic programming solution, along with a practical low-complexity myopic policy.

Findings

Myopic policy approaches optimal performance.

Myopic policy outperforms baseline policies.

Simulation confirms effectiveness of proposed policies.

Abstract

In this paper, we consider a multiuser uplink status update system, where a monitor aims to timely collect randomly generated status updates from multiple end nodes through a shared wireless channel. We adopt the recently proposed metric, termed age of information (AoI), to quantify the information timeliness and freshness. Due to the random generation of the status updates at the end node side, the monitor only grasps a partial knowledge of the status update arrivals. Under such a practical scenario, we aim to address a fundamental multiuser scheduling problem: how to schedule the end nodes to minimize the network-wide AoI? To solve this problem, we formulate it as a partially observable Markov decision process (POMDP), and develop a dynamic programming (DP) algorithm to obtain the optimal scheduling policy. By noting that the optimal policy is computationally prohibitive, we further design a low-complexity myopic policy that only minimizes the one-step expected reward. Simulation results show that the performance of the myopic policy can approach that of the optimal policy, and is better than that of the baseline policy.