volume | PIER Journals

Abstract

Touch interaction is an important function in various electronic systems. In this paper, a touch sensing method based on an electromagnetically induced transparency (EIT) microstrip structure is proposed. The design consists of a U-shaped two-port microstrip transmission line with four open stubs oriented in four directions. Two transmission narrow bands are generated by the proposed structure at around 1.8 GHz and 3.5 GHz, corresponding to the EIT effect. When finger-like objects approach the terminals of these open stubs, their transmission characteristics change significantly, as indicated by variations in the S-parameter response. To precisely determine the touch position, a shifting vector method is introduced based on the variations of S-parameters at different touch positions on the board plane. Both simulation and experimental results demonstrate a touch localization accuracy of 94.4% with a spatial resolution of 3 mm. The proposed design offers a low-cost and compact platform that integrates touch interaction and RF communication, showing strong potential for future interactive electronic and communication systems.

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Dr. Jiyou Jiang

Dr. Jiangtao Huangfu