Design and modeling of surface acoustic wave sensor with staggered ID – tag

Abstract

A design methodology of wireless surface acoustic wave (SAW) sensor with staggered ID – tag is presented. For longer reading distances and technology improvement unidirectional transducers, working on the main frequency harmonics, are proposed. To reduce the number of strips and the size of devices is offered to increase the reflection coefficient and use open circuit reflectors. Unique technological realizations of SAW reflecting elements and unidirectional transducers, that enable to increase reflection coefficient and unidirectionality are proposed. A model of wireless sensor based on transfer matrixes of equivalent circuits of the device elements is created. The model discloses interaction among separate elements, assessed charge distribution in electrode's type, secondary effects, losses, wave's speed change constituents and allows to analyze characteristics and parameters of SAW sensors that have various structures. Simulation results are presented.