Bailigh: Low Power Cross-Layer Data Gathering Protocol for Wireless Sensor Networks

Data gathering systems are an important class of Wireless Sensor Networks (WSNs). As the goals of such systems are long lifetime, high reliability, and unattended operation, efficient use of limited energy is crucial. This paper presents Bailigh, a low power cross-layer protocol designed for low rate periodic data collection. Bailigh schedules the network to wake up at regular intervals for brief periods of data collection. To achieve this Bailigh integrates synchronous low power listening and network level scheduling. The proposed synchronous low power listening technique mitigates clock drift with low overhead and reduces unnecessary radio usage. Integrated scheduling enables staggered communication, which effectively reduces collisions and increases delivery rate. We use simulations to compare the proposed approach with a non cross-layer approach. Results show an average duty cycle of 0.1% and delivery rate of 95%. With duty cycle 8.7 times lower than LPL, Bailigh offers network lifetime of 5.8 years.