An Efficient Backoff Scheme in Wireless Sensor Networks

The IEEE 802.15.4 protocol is designed to provide for connecting low data rate devices with low-power in wireless personal area network (LR-WPAN). In IEEE 802.15.4, a slotted carrier sensing multiple access with collision avoidance (CSMA/CA) algorithm is employed to coordinate a large number of sensor devices. Energy consumption requirements make it to use fewer number of backoffs, which adversely increases collisions, resulting in degradation of energy consumption. In this paper, we present a novel scheme to improve both network throughput and energy efficiency. We develop a Markov model for the proposed scheme with the provision of mathematical analysis, which is validated via experiments using ns- 2 simulator. It is shown that the proposed scheme significantly enhances the performance in respect of both network throughput and energy efficiency.