Efficient and Accurate Calculation of the Cutoff Wavenumbers of Coaxial Elliptical-Circular and Circular-Elliptical Metallic Waveguides

Abstract

In this paper, we propose an efficient method for the calculation of the cutoff wavenumbers of coaxial elliptical-circular and circular-elliptical metallic waveguides. The cutoff wavenumbers are obtained through closed-form expressions making the evaluation efficient, and moreover, very accurate even for large values of the eccentricity of the elliptical boundary. The resulting formulas are free of Mathieu functions, including only simple algebraic expressions with Bessel functions, and are valid for every different value of the indices and , corresponding to every higher order or mode. The validation of the method is performed by comparing to the general exact solution. The efficiency and accuracy of our method is presented by illustrative examples. Numerical results are given for the cutoff wavenumbers of various higher order modes.

TEM‐TE 11 mode converter antenna like a pelican beak

“…The sectorial waveguides consist of a semi-circular core and a semi-elliptical body. Kolezas et al [33] can be used to find the phase constant of the elliptical-sectorial waveguide. It is, of course, noteworthy that [33] explains a waveguide, consists of a circular inner and an elliptical body.…”

“…Kolezas et al [33] can be used to find the phase constant of the elliptical-sectorial waveguide. It is, of course, noteworthy that [33] explains a waveguide, consists of a circular inner and an elliptical body. Due to the OTE 11 mode is excited, in the elliptical-sectorial waveguide of the PBMCA, and also, the elliptical-sectorial waveguide is created by connecting the small diameter of the coaxial-elliptical waveguide, the phase constant of the elliptical-sectorial waveguide is equal to the coaxial-elliptical waveguide with a circular inner.…”

“…The reason for the issue is that in sectorial waveguides, the electrical fields that are perpendicular to the cut plane can be considered in the same direction as the image theorem. According to [33], for a coaxial elliptical waveguide with a circular inner, we have…”

“…Also, g nm 2 = x nm 2 / x nm 0 and g nm 4 = x nm 4 / x nm 0 . Now, x nm 2 and x nm 4 can be calculated as [33,34]. Finally, the phase constant of the elliptical-sectorial waveguide can be calculated by the following equation:…”

Analytical expressions of the Q ‐factor for the complete resonant mode spectrum of the equilateral triangular waveguide cavity

“…Introduction: Waveguide theory [1,2] is a fundamental field in the microwave and millimetre-wave domain, where developing analytical formulations for mode propagation is an active field [3,4] with numerous applications in high-frequency systems for communications, radioastronomy or plasma physics. In the microwave and millimetre-wave regime, a very common wave-guiding system is a single-conductor pipe filled with a homogeneous isotropic dielectric.…”