Transmission Lines to Enhance the Reading of UHF RFID Tags on Small Metallic Objects

This paper presents an antenna-like passive structure that allows to read miniaturized UHF RFID tags attached to small metallic objects. The solution is realized by combing far-field Wireless Power Transfer (WPT) with a Conductor-Baked Coplanar Waveguide (CBCPW) transmission line. Low cost proof-of-concept prototypes were realized on a FR4 substrate. Measurements are in good agreement with simulations. A maximum read range of 2.20 m can be achieved for the far-field operation.

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