Whittle Index for AoI-Aware Scheduling

Abstract

We consider a system consisting of multiple sensors that send updates to a monitoring station via a shared communication channel. The focus is on designing scheduling policies to minimize the time-average of the weighted sum of the Age-of-Information of the sensors. We consider multiple channel models (i.i.d./Markov) and multiple information settings (CSI/delayed CSI/no CSI) and show that the scheduling problem is indexable for all settings considered. In addition, we compute the Whittle index in closed form for some of the settings. Via simulations, we show that Whittle Index based scheduling policies either outperform or match the performance of the best-known policy for all the settings studied.