A class of angular-displacement microwave sensor based on a microwave signal-interference transversal filtering section (TFS) with unequal-electrical-length paths is reported for the first time. It consists of a bi-path TFS composed of two in-parallel transmission-line segments with distinct lengths, which is modified by adding a rotational open-circuit-ended stub as the rotor to a curved section as the stator of one of its line segments. In this manner, the spectral positions of the transmission zeros, which are produced in its filtering transfer function through destructive signal-energy interactions, are modified with the rotation of this additional stub. This allows single/multi-band angular-displacement microwave-sensing capabilities in terms of transmission-zero inter-spacing variation for passbands/stopbands and stopband-peak-level modification to be attained by means of the mechanical rotation of the rotor. The theoretical operational principles of this type of bi-path-TFS-based angular-displacement microwave sensor and design curves for specific values of its electrical parameters are provided. Moreover, for experimental validation purposes, a proof-of-concept prototype of the devised TFS-based microwave-sensor approach operating at 961 MHz with 180° dynamic range is prototyped in microstrip technology and measured. A comparative analysis of the developed angular-displacement microwave sensor with the state-of-the-art is also presented.

中文翻译：

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使用不等长双路横向滤波部分的角位移微波传感器

首次报道了一类基于具有不等电长度路径的微波信号干扰横向滤波段(TFS)的角位移微波传感器。它由一个双路径 TFS 组成，该 TFS 由两个具有不同长度的平行传输线段组成，通过将旋转开路端短截线作为转子添加到弯曲部分作为其线路之一的定子进行修改段。以这种方式，通过破坏性信号-能量相互作用在其滤波传递函数中产生的传输零点的频谱位置随着该附加短截线的旋转而被修改。这允许通过转子的机械旋转获得在通带/阻带的传输零间距变化和阻带峰值电平修改方面的单/多带角位移微波传感能力。提供了这种基于双路径 TFS 的角位移微波传感器的理论工作原理及其电气参数特定值的设计曲线。此外，出于实验验证的目的，设计的基于 TFS 的微波传感器方法的概念验证原型在 961 MHz 下工作，动态范围为 180°，采用微带技术进行原型设计并进行测量。还介绍了已开发的角位移微波传感器与最先进技术的比较分析。