WLC35-4: Optimizing Energy Efficiency in Polling-Based Wireless Networks with Stability Constraints

In this paper we consider the problem of minimizing the total energy for all devices in a wireless infrastructure network. The wireless devices use transmission power control and power saving mode to conserve energy. In particular we consider a polling-based MAC protocol which determines optimal power schedules (therefore the transmission rates) for all devices. Moreover, we have considered two grouping schedules: Phase Grouping (PG) and Mobile Grouping (MG). Through an iterative algorithm, we compute and compare the suboptimal energy consumptions for the two schedules based on the number of bits transmitted per joule of energy. Extensive results show that the MG schedule is much more energy efficient than the PG schedule, and the main sources of energy saving come from the reception and mode transition phases. Moreover, we evaluate the impact of an uncooperative user, who does not follow the optimal power allocation, on its own and others´ energy-delay performance.