Information freshness over a Markov channel: The effect of channel state information

摘要

We consider a communication problem in which a source desires to maintain the freshness of the information updates it sends to a destination, over a channel that varies according to a Markov chain. Freshness is quantified in terms of the age metric (unlike the familiar delay metric), which refers to the difference between the current time and the time of generation of the most recently received update. We then address the impact of channel state information (CSI) on information freshness. Using CSI, transmissions can be adapted to current channel conditions to improve system performance. The following cases are considered: unknown CSI, perfect CSI, erroneous CSI, and delayed CSI. (C) 2018 Elsevier B.V. All rights reserved.