Microwave Angular Displacement Sensor Using Cross-Shaped Coupled-Line Resonator

In this paper, a novel microwave angular displacement sensor based on the cross-shaped coupled-line resonator (CSCLR) is presented. The proposed sensor consists of two substrate layers where a spilt ring is placed in the top layer as a rotor and the coupled lines are placed in the bottom layer as a stator. When the rotor is in its initial state (α=0°), the sensor obtains a wideband bandpass filtering response, which can be used as a wideband bandpass filter. By rotating the rotor (α>0°) in the top layer, the out-of-band transmission zero can obtain a relatively linear variation, realizing a satisfying angular sensing function. A prototype is designed and simulated. The results show that the proposed sensor can obtain a relative linear variation and an averaged sensitivity Sav = 6.5MHz /°.