Power saving scheduling with QoS guarantee in IEEE 802.16e networks

In order to reduce power consumption of mobile stations (MS) in IEEE 802.16e networks, three types of power saving classes (PSC) are defined in 802.16e as one of the extensions to 802.16. However, the standard does not define how to set the PSC parameters to guarantee the QoS of connections and how to coordinate different PSCs. In this paper, a type II PSC setting algorithm for multiple MSs with real-time connections in IEEE 802.16e networks is proposed. The goal of the algorithm is to maximize the total power saving of the MSs and guarantee the packet delay bound of each real-time connection. The proposed algorithm is compared with the state-of-the-art algorithm and the theoretical optimal limit through simulations. The simulation results show that the proposed algorithm can achieve more power saving than the state-of-the-art algorithm. When there are 5 connections per MS, the performance of the proposed algorithm is just 1% less than the theoretical optimal limit.