Duty cycle control for low-power-listening MAC protocols

Energy efficiency is of the utmost importance in wireless sensor networks. The family of low-power-listening MAC protocols was proposed to reduce one form of energy dissipation-idle listening, a radio state for which the energy consumption cannot be neglected. Low-power-listening (also called channel probing) MAC protocols are characterized by a duty cycle: a node probes the channel every t_i s of sleep. A low duty cycle favors receiving nodes because they may sleep for longer periods of time, but at the same time, contention may increase locally, thereby reducing the number of packets that can be sent. We propose a new approach to dynamically control the duty cycle so that the target rate of transmitted packets is reached, while the consumed energy is minimized. Our approach utilizes control theory and adapts it to the control of t_i for low-power-listening MAC protocols in wireless sensor networks. Results show that this approach can appropriately adjust t_i to the current network conditions.