Abstract

Abstract- Wireless sensor network applications, similarly to other distributed systems, often require a scalable time synchronization service enabling data consistency and coordination. This paper introduces the robust Flooding Time Synchronization Protocol (FTSP), especially tailored for applications requiring stringent precision on resource limited wireless platforms. The proposed time synchronization protocol utilizes low communication bandwidth, scales well for medium sized multi-hop networks, and is robust against topology changes and node failures. The FTSP achieves its robustness by utilizing periodic radio broadcast of synchronization messages, and implicit dynamic topology update. The unique high precision performance is reached by utilizing MAC-layer time-stamping, comprehensive error compensation, including linear regression, which reduces time skew and keeps network traffic overhead low. The performance of the FTSP, implemented on Berkeley MICA2 platform, was evaluated in a multi-hop experiment. The average network-wide synchronization error was in the microsecond range, which is approximately a magnitude lower than that of the existing RBS and TPSN algorithms. The protocol was further validated as part of our counter-sniper system that was field tested in a US military facility. 1.

Citations