On Emptying a Wireless Network with Minimum-Energy Under Age Constraints

Timely information delivery and low energy consumption are of critical importance for a variety of wireless applications. In this paper, we address the link scheduling problem of emptying a network with minimum energy, subject to a maximum peak age constraint for each information source. We formulate the minimum-energy scheduling with age constraints (MESA) problem in its general form and prove that it is NP-hard. We derive fundamental results, such as lower and upper bounds of the minimum energy consumption, and the conditions when a TDMA schedule is optimal. We propose the deadline-first-with-revision (DFR) algorithm for constructing a scheduling solution, and evaluate its performance under two rate functions. Numerical results show that DFR achieves a significant energy reduction compared to a minimum age scheduling solution.