Microwave Rotation Sensor Based on Reflection Phase in Transmission Lines Terminated with Lumped Resonators

• Published in: IEEE sensors journal Vol. 23; no. 7; p. 1
• Main Authors: Mehrjoo, Zahra, Ebrahimi, Amir, Beziuk, Grzegorz, Martin, Ferran, Ghorbani, Kamran
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-04-2023; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Capacitance; Circuit design; Coplanar waveguides; Frequency measurement; Input impedance; Integrated circuit modeling; Microwave sensors; phase variation sensors; Reflectance; reflective mode sensors; Resonators; Rotation; rotation sensors; Sensors; Slabs; Tapering; Transmission line measurements; Transmission lines
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2023.3236638

A phase variation-based rotation sensor is presented in this paper. The sensor is realized using a coplanar waveguide (CPW) terminated with a stepped impedance LC resonator. A circular dielectric slab is rotating above the resonator. Rotation of the slab modifies the overall capacitance and thus the input impedance of the resonator. This, in turn, modifies phase of the reflection coefficient, which is translated to the rotation angle. The sensor's linearity is eventually enhanced by tapering the width of the capacitive metallic patch along the rotation direction. The operation and sensing performance is studied in detail, using a circuit-based analysis and electromagnetic simulations. The designed sensor is capable of detecting the direction of rotation. A sensor prototype is fabricated and experimentally measured to prove the developed design and analysis procedure.