ANALYSIS OF ARBITRARILY TRAPEZOIDAL-GROOVE GUIDE WITH THE CONFORMAL MAPPING METHOD

The arbitrarily open trapezoidal-groove guide is analyzed with the conformal mapping technique. A new formula is given for the evaluation of one fundamental parameter associated with the technique. The relationship between the cut-off wavelength for the dominant mode and the geometry of the guide structure is studied; dispersion characteristic of the groove guide is also given. Some numerical results are shown to be in good agreement with both experimental data and the results of the finite element method (FEM). Moreover, it is testified that dispersion of the trapezoidal-groove guide is low. The obtained results are significant for the design and application of the open trapezoidal-groove guide for millimeter waves.     

On the Dominant Mode in Closed Trapezoidal-Groove Guide by Finite Element Method

The structure of closed trapezoidal-groove guide is similiar to that of open one, but it can be used to prevent energy from leaking out of the guide. In this paper, the propagation characteristics of dominant mode in closed trapezoidal-groove guide are analysed by using finite element method and the results are discussed.     

Transmission Properties of Closed Trapezoidal-Groove Guide for Millimeter Waves

The transmission characteristics of the mode TE₁₁ for a new type of closed trapezoidal-groove guide with arbitrary inclined angle are analysed in detail with the mode-matching method in this paper. The calculated results are in good agreement with the experimental values in the published reference. The dispersion of the closed trapezoidal-groove guide is very low. The relationships of the cut-off wavelength and the attenuation constant with the structural sizes of the closed trapezoidal-groove waveguide are also obtained. The given results have very important value in study, design, manufacture and application for closed trapezoidal-groove waveguide.     

An improved solution to the dominant mode properties of groove guides of general cross section

An improved solution to the dominant mode properties of groove guides of general cross section is presented in this paper. A novel differential equation is formulated and solved by numerical integration technique. Numerical results for single V-groove guide show good agreement with available measured values. Calculated results for the cutoff wavelengths of semicircular-groove and trapezoidal-groove guides are presented.     

On the Main Mode of Trapezoidal-Groove Guide By Finite Element Method

In this paper, the propagation properties such as the dispersion characteristics, cut-off wavelength, guide wavelength and field distribution for the main mode of trapezoidal-groove guide are analysed by using the finite element method. The dispersion is very low, and the field distribution in a trapezoidal-groove guide is similar to that of rectangular one. The results have important values in design, manufacture, and application of groove guides.     

Analysis for Transmission Properties of Arbitrarily Trapezoidal-Groove Waveguide for Millimeter Waves

In this paper, the transmission properties such as the dispersion and attenuation characteristics for the dominant mode of the trapezoidal-groove waveguide with arbitrarily inclined angle are analyzed and discussed by using the mode-matching method. Some calculated results are in very good agreement with the published data. The obtained conclusions are of important significance in theoretical studies and actual applications of trapezoidal-groove waveguides for millimeter and submillimeter waves.     

Analysis for dispersion characteristics of trapezoidal-groove waveguide

In this paper, the dispersion characteristics of the main mode for the trapezoidal-groove guides are analysed by using the approach of equivalent network with transverse resonance. The relationship curves between guide wavelength, phase constant and guide dimensions, frequency are obtained. The characteristics have important values in design, manufacture and application of groove guides.     

Study on Transmission Characteristics of Trapezoidal-Groove Guide with Mode-Matching Method

In this paper, the dispersion, cut-off and attenuation characteristics of trapezoidal-groove guide are analyzed by using the mode-matching method. The relationships between the guided parameters and variations of relative guide's sizes are discussed in detail. The calculated results are in good agreement with those in relevant reference. So, the obtained conclusions have important values in theoretical studies and actual applications of trapezoidal-groove guides for millimeter and submillimeter waves.     

Transmission Characteristics with Second Order Approximations of Elliptic-Groove Waveguide

In this paper, the transmission characteristics for the dominant mode H _{e 11} ⁽¹⁾ in the vertical-flat elliptic-groove guide are analysed by using the mode-matching method and Mathieu function. The characteristic equations with the 1st and 2nd order approximations and their solutions for the dominant mode of the elliptic-groove guide are also obtained by a great quantity of theoretical analyses and numerical computations. The cut-off, dispersion and attenuation characteristics are in good agreement with those in the relevant references under limiting conditions and are discussed in detail. The obtained results are of important significance for theoretical researches and actual applications of elliptic-groove guides for millimeter and submillimeter waves.     

Finite Element Analysis of the Dominant Mode Variation in Groove Guide

In this paper, the dominant mode in groove guide is analyzed by finite element method. For the guide with a shallow groove, the electric field lines (abbreviated as E lines) are perpendicular to the parallel plate, which is different from the literatures, and the dominant mode distribution is irrelevant to the groove width; for the guide with a narrow but deeper groove, the E lines are parallel to the plate region, which represents the characteristics of lower attenuation, for the guide with a deeper and wider groove, a complicated E lines are obtained. These results reveal that the dominant mode distribution in groove guide is varied, which replenish our understanding of groove guide, and the results have important values in design, manufacture, and application of groove guide.     

An efficient image guide mode launcher

A three section efficient mode launcher for converting TE₁₀ mode of rectangular wave guide to dielectric image guide mode has been designed and tested experimentally. The transmission loss of the trapped image guide and insulated trapped image guide are also evaluated experimentally using this transition.     

Analysis for Transmission Characteristics of Closed Trapezoidal-Groove Waveguide with Boundary Element Method

In this paper, the cut-off and dispersion characteristics of a new kind of closed trapezoidal-groove waveguide that has more advantages than open groove waveguides are analyzed with the help of the boundary element method, the relationship between cut-off wavelengths and variations of guide's relative sizes is discussed in detail. The calculated results are in good agreement with those in the relevant reference. So, the obtained conclusions are very important in theoretical studies and actual applications of closed trapezoidal-groove waveguides for millimeter and submillimeter waves.     

Field Patterns in Double Circular-Groove Guide by Finite Element Method

The electromagnetic power coupling in symmetrical and asymmetrical double circular-groove guides have been analyzed by finite element method (FEM) in this paper. The electrical field patterns of the dominant mode and the first higher-order TE mode have been presented. The electromagnetic field of the dominant mode distributes with a concentration in the two grooves and the region between grooves as well for symmetrical double circular-groove guide, while it distributes with a concentration in the groove with larger radius for the asymmetrical double circular-groove guide. The electrical field patterns of the first higher-order TE mode in symmetrical and asymmetrical double circular-groove guide are also presented. The figures in this paper have important values in design of circular-groove guide power coupler for millimeter wave applications.     

Analysis of groove NRD waveguide bend using the coupled-mode theory

In this paper, the propagation characteristics of the dominant mode in GNRD guide bend are analysed employing the coupled-mode theory. The curves of bending loss vs. The groove depth or width, radius of curvature and frequency are given, which caused by the mode conversion of the operatingLSM ₁₁ ^x mode to the parasiticLSE ₁₁ ^x mode. It is found that the groove depth has a great influence upon the bending loss than the other parameters. According to the theoretical results, appropriate sizes of groove and radius of curvature should be chosen in designing a GNRD bend structure.     

Finite Element Analysis of Field Pattern in Multiple Groove Guide

Rectangular groove guide with multiple grooves has been analyzed by finite element method (FEM) in this paper. The electrical field patterns of the dominant mode and the first higher-order TE mode have been presented for groove guide with single-, double-, triple-, and quadruple-rectangular grooves. The electromagnetic field of the dominant mode is distributed with a concentration in the groove regions, while the electromagnetic field of the first higher-order TE mode is mainly distributed in regions between grooves. The low loss characteristic has been found not only in single-groove guide, but also in multiple groove guide.     

Finite Element Analysis of the Field Patterns of Higher-Order TE and TM Modes in Rectangular-Groove Guide

The field patterns of the different TE and TM modes in a rectangular-groove guide are analysed by finite element method. The electric field, magnetic field and energy distributions in the groove guide for the dominant TE mode, the lowest TM mode and the 1st, 2nd, and 3rd higher-order TE,TM modes are presented. The results show that the low-loss characteristic of rectangular-groove guide seems unreliable. The results in this paper will be of benefit for us to understand the transmission characteristics of rectangular-groove guide, and will be of practical significance in designing groove guide components.     

The design of a mode selective directional coupler for a high power gyroklystron†

The design method of mode selective directional couplers from a transverse electric mode in a circular waveguide to the fundamental mode in a rectangular wave guide is presented in this paper. The design results for a TE₀₁ circular mode coupler intended for use in the output power measurement of a high power gyroklystron are reported; these results indicate that more than 50-80dB directivity and sufficient suppression of unwanted modes can be obtained with a coupler less than 07m in length. The effects of frequency and rectangular wave guide size on coupler parameters are also discussed in this paper     

Attenuation in corrugated rectangular waveguide

The attenuation characteristics of two corrugated rectangular waveguides propagating the dominant hybrid mode are shown to be significantly better over a wide bandwidth than those for a plain guide propagating the TE10 mode.     

Field Patterns in Asymmetrical Double Groove Guide by Finite Element Method

The electromagnetic power coupling in asymmetrical double-groove guide is analyzed by finite element method (FEM) in this paper. The electrical field patterns of the dominant mode and the first higher-order TE mode have been presented. The electromagnetic field of the dominant mode is distributed with a concentration of energy in the wide groove region, while the electromagnetic field of the first higher-order TE mode is distributed with a concentration of energy in the narrow groove region. The results in this paper have important values in design of groove guide power coupler for millimeter wave applications.     

Impedance Characteristics of Closed Elliptic-Groove Waveguide for Millimeter Waves

A characteristic equation and impedance characteristic for the dominant mode of closed elliptic-groove guide have been analyzed and discussed by using the mode-matching method. The reference size of the closed elliptic-groove guide for the good impedance matching with rectangular guide in actual application is given. The obtained conclusions are of important significance in theoretical studies and actual applications of closed elliptic-groove guide for millimeter waves.