Minimizing Power Cost in QoS Constrained Wireless Sensor Networks

摘要

This paper studies the problem of simultaneous support of energy efficiency and quality of service (QoS) in time division multiple access (TDMA) based wireless sensor networks (WSNs), utilizing the concept of cross-layer optimization. We show that by taking slot reuse into account, the problem has combinatorial complexity, which is determined by the TDMA frame length and the number of links. An iterative reuse factor (IRF) approach is proposed to efficiently solve the problem. By skillfully introducing and iteratively adjusting a slot reuse factor, cross-layer optimization and slot reuse are jointly inter-connected to obtain a TDMA schedule with optimal power consumption and desired QoS objectives in polynomial time. Extensive simulations with a random topology WSN show that the proposed IRF approach provides a flexible tradeoff between energy efficiency and QoS objectives. Under the same packet loss rate objective, the IRF approach achieves up to 30 % of power saving compared to the existing approaches in the literature.