A Novel Dual-Loop Coupler for One-Port Cylindrical Cavity Permittivity Measurement

Abstract

Abstract-The one-port cavity resonator technique based on the S 11 parameter measurement for measuring the complex permittivity of dielectric samples has been proposed. A novel dual-loop coupler is developed for avoiding and suppressing the spurious modes in oneport cavity resonator. Through threading the pair of half loop in the opposite direction, the opposite surface currents can be generated and only TE 011 mode will be excited. The operating principles of the dualloop coupler are investigated. This technique has the advantages of the coupling. Equivalent electronic circuit model has been set up. Simulation and experimental results show good agreement.

Design of a rectangular waveguide to cylindrical cavity mode launcher for TE011mode with maximum quality‐factor

“…Microwave cylindrical cavity has a wide range of applications such as measurement of material properties, filters, resonant systems, and also in high power microwave sources . Various types of excitation techniques of a cylindrical cavity have been investigated extensively in the literature .…”

“…A cylindrical cavity is operated in dominant TE 111 mode and also in TE 011 mode for certain applications like the characterization of materials, measurement of material properties such as dielectric constant and loss tangent. TE 011 mode has a higher quality factor as compared to the dominant TE 111 mode.…”

“…Side wall coupling is also used in the overmoded microwave filters . Method of loop coupling is presented in Reference . In this article, the TE 011 mode is excited from the TE 10 mode of the rectangular waveguide through the top wall of the cylindrical cavity.…”

Prediction of Electric Permittivity of Threads in Woven Fabric

“…Measurement methods of material permittivity are widely described in the literature. [7,8] A summary of these methods together with an assessment of their usefulness for the measurement of textile materials was presented, among others, in [9]. The presented methods most often allow to determine the permittivity of the whole fibrous structure (e.g., fabric) which may differ significantly from the permittivity of threads due to the presence of air spaces in the measured structure.…”

A New Open Cavity at Millimeter Wave Band for Permittivity Measurement of Dielectrics

“…Meanwhile, open cavity is also a power tool for measuring accurately complex permittivity of dielectric materials at millimeter and sub-millimeter wavelengths. How to use this technique to measure the complex permittivity of dielectric material accurately have been investigated in detail [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. All of the open cavities investigated are based on spherical mirrors or spherical and planar mirrors.…”