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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Higher Education Press and Springer-Verlag Berlin Heidelberg