Optimizing Age of Information in Wireless Networks with Perfect Channel State Information

TL;DR

This paper addresses minimizing the Age of Information in wireless networks with perfect channel state information, proposing policies that nearly optimize AoI and significantly outperform previous methods without channel info.

Contribution

It introduces two policies leveraging perfect channel state information, achieving near-optimal AoI and a fourfold improvement over prior work without such information.

Findings

Virtual-queue based policy is nearly optimal, up to a constant additive factor.

Age-based policy is at most four times worse than the optimal.

Availability of channel state information leads to fourfold AoI improvement.

Abstract

Age of information (AoI), defined as the time elapsed since the last received update was generated, is a newly proposed metric to measure the timeliness of information updates in a network. We consider AoI minimization problem for a network with general interference constraints, and time varying channels. We propose two policies, namely, virtual-queue based policy and age-based policy when the channel state is available to the network scheduler at each time step. We prove that the virtual-queue based policy is nearly optimal, up to a constant additive factor, and the age-based policy is at-most factor 4 away from optimality. Comparing with our previous work, which derived age optimal policies when channel state information is not available to the scheduler, we demonstrate a 4 fold improvement in age due to the availability of channel state information.