A. P. Motornenko

On the anisotropy of dielectric permittivity in single crystal lanthanum aluminate substrates

The dielectric properties of LaAlO3 single crystal plates were studied by microwave techniques in a frequency range from 20 to 28 GHz. The measurements were performed using a resonator representing crossed round (cylindrical) and radial evanescent waveguides with the polarization-degenerate fundamental oscillation mode. Various single crystal samples, including those obtained from different manufacturers, exhibit anisotropy in the (100) crystal plane, whereby the permittivity varies within Δε=0.1–0.9.

Measuring the Electric Parameters of Dielectrics at Microwave Frequencies

A technique for the local determination of the permittivities of substances, which uses resonance features of polarization-degenerated HE electromagnetic oscillations in a structure formed by an orthogonal junction of crossed evanescent cylindrical and radial waveguides, is considered. A sample of an isotropic or anisotropic dielectric (a plate of arbitrary shape and size) is placed into the intersection region and partially into the radial waveguide. Permittivities of Ftoroplast-4 fluoroplastic, fused quartz, single-crystal quartz, and other dielectrics measured in a frequency band of 10–70 GHz are presented.

A spherical microwave discharge induced at atmospheric pressure

A discharge induced at the end of an antenna in a flow of argon outgoing into the free space in a coaxial microwave plasmatron is described. Increased energy density supplied to the plasma leads to structuring of the microwave discharge. Effects of the antenna geometry, supplied power, and argon flow rate on the discharge structure are studied.

The whispering-gallery waves in a disk dielectric resonator located on a dielectric substrate

The paper is devoted to investigation of peculiarities of natural azimuthal electromagnetic oscillations in a dielectric resonator located on a substrate, whose permittivity is lower than that of the material of the main resonator. The impact of the dielectric substrate thickness on the spectrum of natural frequencies of the resonant structure is considered. Also, the behavior of electrodynamic characteristics of the resonator as a function of frequency and dielectric substrate’s width is analyzed.

Waveguide-coaxial resonator

Summary form only given. At the present time waveguide-dielectric resonators are widely applied in microwave equipment. These resonators consist of a length of evanescent waveguide inside which the dielectric elements (DE) are located. The availability of two-layer DE in the resonator permits one to increase the measurement accuracy of the electric parameters of a dielectric, to develop equipment with an increased Q-factor on the basis of a resonator with a small size. In this paper a resonator based on an evanescent waveguide with two-layer DE in which an internal layer was replaced by a metal rod, is investigated. In essence, the considered resonator consists of a length of a coaxial line on either side of which a length of cylindrical evanescent waveguide was placed. This resonator is called a waveguide-coaxial resonator (WCR). An experimental study of the WCR in the millimeter-wave band is presented.

Magnetic modes in a resonator built around a circular evanescent waveguide and coaxial line

AbstractThe eigenfrequencies of magnetic modes in a resonator made up of two segments of a circular evanescent waveguide and a coaxial line are found by solving an electrodynamic problem. For the fundamental

Tunable waveguide-dielectric resonator for the millimeter band with increased Q-factor

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A waveguide-coaxial resonator for the millimeter range

mode, the performance of the resonator is studied analytically and experimentally over a wide range of its parameters. The feasibility of a high-power microwave semiconductor oscillator based on the resonator under study is demonstrated.