Time reversal data communications on pipes using guided elastic waves: Part I. Basic principles

Abstract

Piezoelectric sensors that are embedded in large structures and are inter-connected as a sensor network can provide critical information regarding the integrity of the structures being monitored. A viable data communication scheme for sensor networks is needed to ensure effective transmission of messages regarding the structural heath conditions from sensor nodes to the central processing unit. In this paper we develop a time reversal based data communication scheme that utilizes guided elastic waves for structural health monitoring applications. Unlike conventional data communication technologies that use electromagnetic radio waves or acoustical waves, the proposed method utilize elastic waves as message carriers and steel pipes as transmission channels. However, the multi-modal and dispersive characteristics of guided waves make it difficult to interpret the channel responses or to transfer correctly the structural information data along pipes. In this paper, we present the basic principles of the proposed time reversal based pulse position modulation and demonstrate by simulation that this method can effectively overcome channel dispersion, achieve synchronization, and delivery information bits through steels pipes or pipe-like structures correctly.