Power Conservation in ZigBee Networks using Temporal Control

This paper addresses power reduction in wireless sensor networks (WSNs), proposing an application-level solution for the IEEE 802.15.4 compliant ZigBee protocol. ZigBee protocol supports the least power-consuming ´sleep´ mode of operation only for end-nodes that do not route packets. This significantly limits ZigBee´s WSN applications. This paper presents a ZigBee-based power-conserving network design in which a multi-mode scheduler can be used at the application-level for all network nodes that brings the whole net up and down. This allows all nodes to ´deep sleep´, hence increasing the per-node lifetime, leading to an increased overall network lifetime. Results of network simulations with a rate monotonic-based scheduler, schedules operating times for various nodes in the entire network, setting the devices to the lowest power operating mode - sleep mode - for all other times when no operation needs to be performed. When the network wakes up, all nodes necessary for a particular scheduled transmission awake and rebuild the ZigBee network. The paper presents power savings estimates from simulations showing significant advantages over standard ZigBee