A Meander Line-Based Frequency Selective Surface for Strain Sensing

Frequency selective surfaces (FSSs) are periodic arrays of conductive elements that have distinct reflection and transmission responses. In this work, an FSS sensor designed to operate in Ka-band to measure a wide range of uni-directional strain using a meander line-based unit cell is presented. Specifically, the proposed unit cell of the sensor consists of a convoluted meander line geometry designed on a thin dielectric substrate. Strain sensing is achieved by monitoring the change in the resonant frequency of the FSS when under strain that is parallel to an interrogating signal linearly polarized and aligned with the convoluted dimension of the meander line element. Simulation results of strain measurement over two ranges, small-(0%-0.5%) and large-scale (0%-5%), are presented. The simulated results indicate that the sensitivity of the sensor to small-scale strain is 21 MHz/0.1% strain and 230 MHz/1.0% strain for large-scale

Embedded Aperture-Based FSS Sensor

Frequency Selective Surfaces (FSSs) Are Two-Dimensional Periodic Arrays of Electrically Conductive Elements or Apertures that Have a Specific Electromagnetic Reflection And/or Transmission Response. in This Work, an Aperture-Based Sensor Design Was Proposed that is Capable of Sensing Strain When Embedded in a Layered Dielectric Structure (I.e., an Embedded Sensor). an Aperture Approach Was Selected Due to the Potential for Operation in Reflection Mode Without a Conductive Backplane. the Sensor Was Designed to Operate within the K-Band to Improve the Potential Strain Measurement Resolution, as the Unit Cell Dimensions Are Inversely Related to the Operating Frequency and Directly Related to Strain Sensitivity. Simulation Results for the Small-Scale Strain Range of 0-0.5% Are Presented, with a Sensitivity of 20.4 MHz/O.1 % Strain