Scheduling Policies for Age Minimization in Wireless Networks with Unknown Channel State

TL;DR

This paper addresses the challenge of minimizing the age of information in wireless networks with unknown channel states by proposing two scheduling policies that are proven to be near-optimal.

Contribution

It introduces two novel scheduling policies for AoI minimization under unknown channel conditions, with theoretical performance guarantees.

Findings

Virtual queue based policy is peak age optimal up to a constant.

Age-based policy is within a factor of 4 of the optimal age.

Numerical results show both policies are close to optimal.

Abstract

Age of information (AoI) is a recently proposed metric that measures the time elapsed since the generation of the last received information update. We consider the problem of AoI minimization for a network under general interference constraints, and time varying channel. We study the case where the channel statistics are known, but the current channel state is unknown. We propose two scheduling policies, namely, the virtual queue based policy and age-based policy. In the virtual queue based policy, the scheduler schedules links with maximum weighted sum of the virtual queue lengths, while in the age-based policy, the scheduler schedules links with maximum weighted sum of a function of link AoI. We prove that the virtual queue based policy is peak age optimal, up to an additive constant, while the age-based policy is at most factor 4 away from the optimal age. Numerical results suggest that both the proposed policies are, in fact, very close to the optimal.