A UKF-based link adaptation scheme to enhance energy efficiency in wireless sensor networks

Sensor nodes are usually battery operated and therefore energy constrained. Thus, energy conservation becomes one of the foremost priorities in designing the wireless sensor networks (WSNs). We present the enhancements at the medium access control (MAC) layer in order to improve the energy efficiency and increase the longevity of wireless sensor networks. The proposed MAC uses an optimal frame size instead of using a fixed frame size for every transmission. We present our study of the unscented Kalman filter (UKF) approach to predict the optimal frame size. The proposed variable frame size conserves energy as well as enhance the system performance by minimizing the throughput degradation caused by a time varying wireless channel. We designed and verified a different network model to evaluate and analyze the proposed approach. The simulation results show an improvement in energy efficiency of up to 15 %.