Ultra-Wideband Communication for Wireless Sensor Networks in Structural Health Monitoring

摘要

Wireless sensor network(WSN)has shown great promise for structural health monitoring(SHM)of buildings and infrastructure in both severe loading events and progressively deteriorating environmental conditions.To collect near real-time measurements for SHM,it is essential to provision reliable highspeed data transmission among sensor nodes.However,in a massively distributed sensor network,the transmission rate and reliability are severely constrained by the limited power supplied by non-rechargeable batteries.These challenges call for an innovative communication paradigm as the enabling physical-layer air interface for WSNs envisioned for monitoring and diagnosing the structural health of civil engineering facilities.Ultra-wideband(UWB)technology emerges as such a competitive communication paradigm for SHM-oriented WSNs.By virtue of its large bandwidth,UWB signaling comes with many uniquely attractive features for SHM applications:potentially high data rates,robust and low power communications,resilience to multipath fading,immunity to electromagnetic interference,and capability to penetrate walls and ground.On the other hand,there has been barely any work on designing and assessing UWB systems under the unique radio channel characteristics of SHM WSNs.Toward filling this gap,this paper presents an overview of the technical challenges in employing UWB radios in sensory units in wireless SHM networks.Novel solutions are provided to cope with some critical issues,including UWB timing synchronization and UWB-based network medium access control for reliable and ultra-low-power communications.A proof-of-concept field test utilizing the Network for Earthquake Engineering Simulation(NEES)facility is discussed.