The characteristic equation and solution of circular-groove guide

The characteristic equations of circular-groove guide have been given under first-order and second-order approximation. The cutoff wavelength and guide wavelength have been calculated. The theoretical results have been verified by experimental measurements.Supported by the Natural Science Fundation of P. R. China     

The effect of tolerance on characteristic of circular groove guide

The variations in propagating characteristic of circular groove guide due to tolerance are analyzed by using eigen-weighted boundary integral equation method (EWBIEM). Theoretical analysis and experimental results show that as long as the tolerance of circular groove guide is not very large the variations in characteristic of circular groove guide are very small.The Project Supported by National Natural Science Foundation of P.R. China     

The characteristic equations of higher-order modes in circular groove guide

The characteristic equations of higher-order modes, including TE mode and TM mode, are derived in this paper. These equations are very useful for us to understand the mode distribution in circular groove guide.The Project Supported by National Natural Science Foundation of P.R.China     

Theoretical characteristic of asymmetric double circular groove guide

In order to get a better understanding of the coupling properties of asymmetric double circular groove guide, the characteristic equation of this structure has been solved and its theoretical curves has been given and discussed.The Project Supported by National Natural Science Foundation of P.R.China     

Study of coupling between circular groove guide and rectangular groove guide

On the basis of the studies of single circular groove guide and single rectangular groove guide, the coupling of the two waveguides has been researched and the characteristic equation of circular—rectangular groove guide has been given in this paper.The Project Supported by National Natural Science Foundation of P.R. China     

The wide band property of circular groove guide

According to the analyses of the moding properties of circular groove guide, the guide dimension for single mode operation is determined. Our results show that circular groove guide has the advantage of wide band.The Project Supported by National Natural Science Foundation of P.R. China and National Key Laboratory of Millimeter Waves Foundation of P. R. China     

The dominant mode in closed circular groove guide

The structure of closed circular groove guide is similar to that of open circular groove guide, but it can prevent energy from leaking out of the guide. In this paper, the dominant mode in closed circular groove guide is considered. The characteristic equation is derived and solved and the results are discussed.The Project Supported by National Natural Science Foundation of P. R. China and National Key Laboratory of Millimeter Waves Foundation of P. R. China     

Studies on the closed circular groove guide

When the circular-groove guide is closed at the two side ends by metal, its dispersion characteristic is studied in this paper, and theoretical values are presented. The eigen-weighted boundary integral equation method was used here.The Project Supported by National Natural Science Foundation of P.R. China.     

Dominant mode characteristics of circular groove guide

Circular groove guide is a kind of waveguide for millimeter waves with low loss, large dimensions, and low dispersion. In this paper, the dominant mode characteristics of it is analysed. The technique that mode macthing method combines with point matching method is used to derive the Nth-order characteristic equation of the guide. The 1st order, 2nd order and 3rd order approximate curves that the normalized cutoff wavelength of circular groove guide varies with c/a are given. The attenuation curves are given at 1mm, 1.5mm and 3mm wavelength. The numerical results are in well agreement with the experimental results published.Supported by National Science Foundation of P. R. China     

Theoretical analysis of double circular groove guide

On the basis of the analysis of single circular groove guide, the field configuration of double circular groove guide has been investigated, its characteristic equation has been derived and its theoretical performances have also been discussed.The Project Supported by National Natural Science Foundation of P. R. China     

The solution to the q-KdV equation

Let KdV stand for the Nth Gelfand-Dickey reduction of the KP hierarchy. The purpose of this Letter is to show that and KdV solution leads effectively to a solution of the q-approximation of KdV. Two different q-KdV approximations were proposed, first one by Frenkel [Int. Math. Res. Notices 2 (1996) 55] and a variation by Khesin, Lyubashenko and Roger [J. Func. Anal. 143 (1997) 55]. We show there is a dictionary between the solutions of q-KP and the 1-Toda lattice equations, obeying some special requirement; this is based on an algebra isomorphism between difference operators and D-operators, where D f(x) = f(qx). Therefore every notion about the 1-Toda lattice can be transcribed into q-language.     

A variable-gain radiating horn using groove guide

A radiating horn of continuously variable gain using groove-guide is proposed. The beam width in both planes is varied. Some experimental measurements at 100 GHz confirm the behaviour.Work carried out at the University of Wales Institute of Science and Technology, Cardiff, U.K.     

曲折圆形槽波导慢波系统的高频特性

对曲折圆形槽波导新型慢波系统的高频特性进行了研究,通过理论分析和数值计算,得到了它的色散曲线和耦合阻抗表达式,并分析了结构参数变化对色散特性和耦合阻抗的影响。研究表明：当周期变小时色散减弱,耦合阻抗增加;而增大直波导长度时色散变弱,但同时耦合阻抗也会下降。因此较小的周期有利于改善曲折圆形槽波导慢波电路的高频特性。鉴于这种电路的耦合阻抗较低,可以适当地减小直波导长度来提高耦合阻抗。曲折槽波导结合了曲折波导散热能力强、色散特性好、容易加工和槽波导单模工作、低损耗、大尺寸等优点,在毫米波及亚毫米波段的行波管中具有较好的发展前景。     

曲折圆形槽波导慢波系统的高频特性

 对曲折圆形槽波导新型慢波系统的高频特性进行了研究,通过理论分析和数值计算,得到了它的色散曲线和耦合阻抗表达式,并分析了结构参数变化对色散特性和耦合阻抗的影响。研究表明：当周期变小时色散减弱,耦合阻抗增加;而增大直波导长度时色散变弱,但同时耦合阻抗也会下降。因此较小的周期有利于改善曲折圆形槽波导慢波电路的高频特性。鉴于这种电路的耦合阻抗较低,可以适当地减小直波导长度来提高耦合阻抗。曲折槽波导结合了曲折波导散热能力强、色散特性好、容易加工和槽波导单模工作、低损耗、大尺寸等优点,在毫米波及亚毫米波段的行波管中具有较好的发展前景。     

Coupling performance of closed double circular groove guide

Double circular groove guide is a simple structure which can be used to construct directional coupler. In this paper, the coupling property of two uniformly coupled circular groove guides is studied based on the transverse resonance analysing results of closed double circular groove guide.The project supported by National Natural Science Foundation of P.R. China     

Further analysis of asymmetric double circular groove guide

As the development of our previous discussion on asymmetric double circular groove guide, the second-order approximate characteristic equation of this structure has been derived. This analysis will give more accurate result.The Project Supported by National Natural Science Foundation of P. R. China     

The four-state solution of the Yang-Baxter equation

A new four-state solution of the Yang-Baxter equation is constructed with the help of the lowest-dimensional cyclic L-operator related to a three-state R-matrix. Some special choice of the parameters on which this solution depends leads to an exactly solvable spin model on a chain with Hermitian Hamiltonian.     

The series solution of the Marchenko equation

The convergence of a Neumann-series solution of the Marchenko equation in L ₂[x, ∞) is proved and an explicit expression of the series solution is given.     

Analysis of the leaky antenna based on the circular groove guide

The circular groove guide is one of several waveguides that will widely be used at millimeter and submillimeter waveband. The leaky antenna based on the circular groove guide is studied by the method based on a transverse equivalent network in this paper.The Project Supported by National Natural Science Foundation of P.R. China     

A study of radiation from circular groove guide horn

A novel horn antenna for millimeter waves based on circular groove guide is presented and investigated in this paper. Its radiation patterns are calculated by employing the aperture field method. The patterns obtained by experiment show agreement with calculated results.