This letter presents an active feedback microwave sensor with a wide dynamic range and high sensitivity for detecting angular displacement. The sensor comprises two types of movable ring resonators (the rotor), split-ring resonator (SRR) and complement SRR (CSRR), and a modified convex-shaped open complementary split-ring resonator (the stator). The stator is designed with an active circuitry to enhance the quality factor over 4.7 K, and the feedback loop surrounds the sensing zone to enhance the mutual coupling for tracking a finite rotation of rotors in a wide dynamic range. The stator uses the separation between two reflection coefficients or the decibel magnitude variation at a fixed frequency, which is generated from its resonance frequency shift and whose values vary as a function of the rotation angle to be measured. After rotor loading, the average decibel sensitivity in terms of variation in reflection was calculated as 0.32 and 0.13 dB/degree for the SRR and CSRR, respectively, within a dynamic range of 0°–90°.

中文翻译：

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一种基于角位移传感器的有源反馈开放式互补裂环谐振器

这封信提出了一种具有宽动态范围和高灵敏度的有源反馈微波传感器，用于检测角位移。该传感器包括两种可动环谐振器（转子）、裂环谐振器（SRR）和互补SRR（CSRR），以及改进的凸形开口互补裂环谐振器（定子）。定子采用有源电路设计，品质因数提高到 4.7 K 以上，反馈回路环绕传感区以增强互耦，以在宽动态范围内跟踪转子的有限旋转。定子使用两个反射系数之间的间隔或固定频率下的分贝幅度变化，这是由其共振频移产生的，其值作为要测量的旋转角度的函数而变化。转子加载后，