Power-efficient wireless sensor reachback for SHM

Wireless sensor networks have recently received great attention from the scientic community, because they hold the key to revolutionize many aspects of our economy and life. On the other hand, the design, implementation and operation of a wireless sensor network in a SHM system requires the synergy of many disciplines, including civil engineering, signal processing, networking, etc. The process of collecting the measurements acquired by a sensor network into a central sink node, constitutes one of the main challenges in this area of research and is often referred to as the sensor reachback problem. In this work, we describe a time-division multiple-access based protocol for sensor reachback, that takes into account the fact that sensor measurements are correlated in time and space, in order to reduce the amount of information that needs to be transmitted at the sink node. Furthermore, cooperative communication is incorporated into the developed protocol, so as to achieve reduced energy consumption. Experiments with real acceleration measurements, obtained from the Canton Tower in China during an earthquake, have demonstrated the effectiveness of the proposed method.