Improved Cylindrical Cavity With Symmetric Double Ridges for High-Sensitivity Detection

In this letter, an improved cylindrical cavity for high-sensitivity detection is proposed. The cylindrical cavity is characterized by symmetric double ridges inside. The double-ridged cavity realizes the electric field compression of TE $_{\mathbf {01}{n}}$ modes by loading two symmetric metal ridges and further greatly improves the detection sensitivity. The parameters of the ridge are optimized and determined by considering the compromise between frequency detection sensitivity, quality factor, and the current fabrication technique. Several fiber monofilaments with diameters of only a dozen micros are separately inserted into the cavity and detected. To illustrate more clearly the advantage of the proposed cavity for the detection of slim materials, the sensitivity per unit of volume (0.32%) is compared and the value is higher than the related research works.

[1]  Pei Peng,et al.  Microwave Sensor Loaded With Complementary Curved Ring Resonator for Material Permittivity Detection , 2022, IEEE Sensors Journal.

[2]  H. Deng,et al.  High Sensitivity Sensor Loaded With Octagonal Spiral Resonators for Retrieval of Solid Material Permittivity , 2021, IEEE Sensors Journal.

[3]  Wensheng Zhao,et al.  An Ultrahigh Sensitivity Microwave Sensor for Microfluidic Applications , 2020, IEEE Microwave and Wireless Components Letters.

[4]  J. Jelonnek,et al.  Dielectric Measurements of PAN Precursor and Stabilized Fibers , 2020, 2020 German Microwave Conference (GeMiC).

[5]  Ali A. Abduljabar,et al.  High $Q$ Microwave Microfluidic Sensor Using a Central Gap Ring Resonator , 2020, IEEE Transactions on Microwave Theory and Techniques.

[6]  D. Mitra,et al.  Design of metamaterial-based compact and highly sensitive microwave liquid sensor , 2019, Applied Physics A.

[7]  Lai-fei Cheng,et al.  Mechanical and Dielectric Properties of Two Types of Si3N4 Fibers Annealed at Elevated Temperatures , 2018, Materials.

[8]  Mojgan Daneshmand,et al.  Strongly Enhanced Sensitivity in Planar Microwave Sensors Based on Metamaterial Coupling , 2017, IEEE Transactions on Microwave Theory and Techniques.

[9]  David J. Rowe,et al.  Improved Split-Ring Resonator for Microfluidic Sensing , 2014, IEEE Transactions on Microwave Theory and Techniques.

[10]  Kausik Bal,et al.  Permittivity of woven fabrics: A comparison of dielectric formulas for air-fiber mixture , 2010, IEEE Transactions on Dielectrics and Electrical Insulation.

[11]  C. P. Neo,et al.  Microwave Electronics: Measurement and Materials Characterization , 2004 .

[12]  Swen Kortig,et al.  Foundations For Microwave Engineering , 2016 .

[13]  W. Marsden.  I and J , 2012 .