Reliable data collection from mobile users with high data rates in wireless sensor networks

Reliably collecting data from mobile sensor nodes is essential with the increasing popularity of integrating mobile nodes into stationary sensor network infrastructure for various scientific and social applications. Existing sensor data collection protocols demonstrate high reliability in stationary sensor networks, but when applied to mobile nodes, the packet acceptance ratio drops significantly. This is because the topology changes due to mobility are not well detected by routing protocols. We present Location-Aware Relay Association Protocol (LRP), a relay association protocol that is independent of any routing protocols and adopts distance measurement techniques to detect topology changes. Instead of reinventing yet another routing protocol, LRP complements it by estimating the distances between a mobile node and its current parent node in the infrastructure network. LRP notifies the routing protocol to trigger route refreshes when a node moves out of the effective communication range of its parent. By continuously adapting to changing topologies in a fast and efficient manner, LRP improves the network reliability and throughput when nodes are moving. In test bed experiments, LRP achieves higher network throughput and lower control overhead than other comparable protocol in data collection applications with high data rate under various mobile environments.