ABSTRACT In this paper, a novel triple-band microwave chip-less sensor tag is presented for Structural Health Monitoring (SHM) systems. Remote sensing capability of microwave devices is employed here to design a sensor for crack detection in metallic structures. The cracks occurred by natural fatigue or human-made mistakes can be distinguished by desired sensor tags. Triple-band operation of the proposed sensor tag at C and X frequency bands is considered here to precisely detect the narrow-width cracks and their directions. In RCS calculations, the resonant frequencies of the designed sensor tag are displaced at the presence of cracks on its ground plane. The proposed sensor tag can detect cracks with a resolution of 0.2 mm which shows a RCS resonant frequency shift of at least 21.1 MHz. This is a big improvement of detectable range in SHM applications compared to the current sensors.

中文翻译：

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一种用于结构健康监测应用的新型三频微波无芯片传感器标签

摘要 在本文中，提出了一种用于结构健康监测 (SHM) 系统的新型三频微波无芯片传感器标签。这里利用微波设备的遥感能力来设计用于金属结构裂纹检测的传感器。可以通过所需的传感器标签区分自然疲劳或人为错误造成的裂纹。这里考虑了在 C 和 X 频段上提出的传感器标签的三频操作，以精确检测窄宽度裂缝及其方向。在 RCS 计算中，设计的传感器标签的谐振频率在其接地平面上存在裂缝时发生位移。所提出的传感器标签可以检测分辨率为 0.2 mm 的裂纹，这表明 RCS 谐振频移至少为 21.1 MHz。