Scheduling Status Updates to Minimize Age of Information with an Energy Harvesting Sensor


IEEE International Symposium on Information Theory (ISIT), Aachen, Germany, 25 - 30 June 2017, pp.1122-1126 identifier

  • Publication Type: Conference Paper / Full Text
  • City: Aachen
  • Country: Germany
  • Page Numbers: pp.1122-1126
  • Middle East Technical University Affiliated: Yes


Age of Information is a measure of the freshness of status updates in monitoring applications and update-based systems. We study a real-time sensing scenario with a sensor which is restricted by time-varying energy constraints and battery limitations. The sensor sends updates over a packet erasure channel with no feedback. The problem of finding an age-optimal threshold policy, with the transmission threshold being a function of the energy state and the estimated current age, is formulated. The average age is analyzed for the unit battery scenario under a memoryless energy arrival process. Somewhat surprisingly, for any finite arrival rate of energy, there is a positive age threshold for transmission, which corresponding to transmitting at a rate lower than that dictated by the rate of energy arrivals. A lower bound on the average age is obtained for general battery size.