Effects of environmental media on the transmission of an inductive link in wireless microsystems

Abstract

An inductive link between two magnetically coupled coils in wireless microsystems is modeled by considering an additional parasitic capacitive link to describe the effect of environmental media. With a system of inductor-capacitor passive wireless sensors, the effects of environmental media are studied theoretically and experimentally for the first time. Results suggest that the capacitive link is non-negligible when the distance between the two coupled coils is comparable with the coupling area, particularly when the environmental medium has a large dielectric constant.

Keywords

capacitive link / monitoring correction / passive wireless sensor

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant Nos. 61136006 and 61401084) and the National High Technology Research and Development Program of China (Grant No. 2015AA042602).

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2017 Higher Education Press and Springer-Verlag Berlin Heidelberg