填充多层互易手征介质金属同轴线传播特性

 采用在圆柱坐标系中分离变量的方法，推出填充多层互易手征介质的金属同轴线各层电磁场之间的关系，得到其模式特征方程和圆波导模式特征方程，给出了填充两层手征介质金属同轴线部分模式的色散特性的数值计算结果，分析了手征介质参量及两层手征介质厚度变化等对手征同轴线传播特性的影响。如果互易手征介质的手征参数等于零，可得填充普通介质的同轴线的模式特征方程。与填充普通介质的同轴线中的模式相比，手征同轴线中的模式发生了分叉。当同轴线中所填介质的折射率增大时，其模式归一化截止频率和进行基模单模传输的带宽归一化频率都将减小。     

Wave numbers of partially filled rectangular waveguide

An approximate method is proposed for determination of the wave numbers of a partially filled rec angular waveguide. The method employs the eigenvalues and parameters of Mathieu equations. The natural H-and E-waves of a partially filled rectangular waveguide are expressed in terms of Mathieu functions. Numerical results of waven number studies are presented and interpreted graphically.     

Eigenfunctions of a partially filled rectangular waveguide

Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 33, No. 12, pp. 1385–1390, December, 1990.     

Nonlinear waves in a waveguide partially filled with a plasma

Nonlinear waves have been studied in a circular waveguide partially filled with a cold magnetized collisionless plasma. The solution obtained is periodical with the frequency increasing as a square root of the amplitude of the solution in the first approximation.The author is indebted to K.Jungwirth, R.Klíma and J.Preinhaelter for valuable discussions.     

Theoretical study of wave propagation along the coaxial waveguide filled with moving magnetized plasma

This paper presents detailed theoretical study on the theory of wave propagation along the coaxial waveguide filled with moving magnetized plasma (CWMMP). Making use of the Lorentz transformation and the constitutive transformation, Maxwell’s equations lead to the coupled non-homogeneous differential equations which govern the wave propagation in CWMMP, and then analytical solutions have been obtained. The discussion about the eigenvalues of the waves and detailed studies on the fields are carried out. It finds that the fields of the CWMMP are composed of two parts with different eigenvalues. Numerical calculations show that because of Doppler shift effect, the eigenvalues of the modes in such a case is quite different from those of the CWMMP. And a detailed discussion on the dispersion characteristic of CWMMP is presented.     

Nonlinear wave processes in media containing cracks partially filled with a viscous liquid

A nonlinear (in the cubic approximation) relaxation equation of state is derived for a rod containing cracks partially filled with an incompressible viscous liquid. The nonlinear effects of the self-action and interaction of low-and high-frequency longitudinal elastic waves propagating in such a rod are studied for the cases of identical and size-varied cracks. Linear and nonlinear acoustic parameters characterizing the self-action and interaction of elastic waves in a cracked rod are determined.     

外开槽同轴波导传播特性

 根据满足边界条件的一系列电磁场方程,采用场匹配法,详细推导了外开槽同轴波导的特征方程。在外开槽同轴波导光滑内同轴半径等于零的情形下,即变成外开槽圆波导,得到其特征方程。数值模拟了外开槽同轴波导及外开槽圆波导中TE₀₁模式的传播特性,得到了不同尺寸外开槽同轴波导开槽间隙半张角和槽深与特征根的变化关系。结果表明:开槽越深,间隙半张角越小,特征根值越小。     

The problem of matching the coaxial resonator of a waveguide synchrotron with the waveguide channel

The matching of the accelerating system with the waveguide channel has a great effect on the stability of operation of a waveguide synchrotron. The experimental matching of the connecting window is a very time-consuming operation. In this paper a formula is derived which will permit the determination by a numerical method of the standing wave ratio (SWR) in the channel as a function of the geometric dimensions of the matching transformer and the resonator Q-factor; experimental results are also given.Translated from Izvestiya Vysshlkh Uchebnykh Zavedenii Fizika, No. 10, pp. 104–108, October, 1971.     

半径渐变同轴波导模式耦合系数研究

 为了用耦合波理论研究一些同轴结构的高频特性，推导了半径渐变同轴波导内模式耦合系数的计算公式，发现半径渐变圆波导模式耦合系数只是同轴波导模式耦合系数的特例。对同轴波导中的模式及其本征方程根的特点进行了讨论，通过建立同轴波导模式和矩形波导模式之间的对应关系，给出了同轴波导模式本征方程根的快速计算方法。对所给模式耦合系数公式进行了验证，耦合波理论计算结果与有限元方法计算结果吻合良好。     

Subwavelength rectangular cavity partially filled with left-handed materials

In this paper, we present the electromagnetic analysis of a rectangular cavity partially filled with a left-handed material slab. Our theoretical investigation shows that there exist novel resonant modes in the cavity, and such a cavity becomes a subwavelength cavity. The eigenvalue equation of the cavity is derived and the resonant frequencies of the novel modes are calculated by using numerical simulation. We also discuss the stability of the novel resonant modes and show the best condition under which a useful rectangular cavity of subwavelength dimensions with tolerable stability is obtained.     

高功率同轴波导Ubitron放大器的高频特性研究

 用三维非线性理论,对高功率同轴波导Ubitron放大器进行了研究。该Ubitron放大器采用环形相对论电子注与同轴波导的TE₀₁模相互作用。通过数值模拟,在Ku波段得到了2.24MW的输出功率,其效率为10.9%,带宽为35% 。数值计算结果表明：电子注的自场导致饱和功率减少,频带变窄,增益下降。使用摇摆器幅值渐变,器件工作效率从10.9%提高到12.3%。     

Nonlinear wave processes in porous waterlike media containing a system of capillaries partially filled with a viscous liquid

A nonlinear dynamic state equation of waterlike porous material that contains a system of cylindrical capillaries partially filled with viscous liquid was received. It is shown that an acoustic nonlinearity of such media contains the relaxation elastic and inelastic components due to the nonlinear dependence of the capillary and viscous pressure in fluid on the capillary diameter. For the medium, theoretical study of such nonlinear phenomena as generation of the second harmonic and a difference frequency wave, self-demodulation of high-frequency pulses as well as the change in the propagation velocity and absorption coefficient of a test wave being under an action of static loading have been carried out. The frequency dependences of medium nonlinearity parameters for these processes were determined.     

脊加载同轴交错圆盘波导的高频特性

提出脊加载同轴交错圆盘波导慢波结构,并用电磁场仿真软件HFSS对其色散特性和耦合阻抗进行了计算,分析了不同结构参数对其高频特性的影响。研究表明:脊加载同轴交错圆盘波导有较好的色散特性,它比非同轴结构的带宽有明显增加,同时可以降低慢波结构的相速,用作行波管慢波结构时可以降低工作电压。脊加载同轴交错圆盘波导是一种全金属结构,散热性能好,损耗低,在毫米波及亚毫米波段的行波管中有较好的应用前景。     

同轴转弯波导的设计与实验研究

提出了一种同轴转弯波导。介绍了该同轴转弯波导的基本原理,设计并数值模拟了中心频率为4.0 GHz的同轴转弯波导,并对此同轴转弯波导进行了实验研究。实验结果表明:同轴转弯波导在中心频率4.0 GHz下,传输损耗约为0.17 dB,驻波系数为1.2;在3.8~4.2 GHz的频率范围内传输损耗小于0.2 dB,驻波系数小于1.25。同轴转弯波导内部无介质支撑,且体积小,结构简单,易于实现,适用于高功率微波馈线系统中的同轴波导的转弯和连接。     

Contactless measurement of the conductivity of II–VI epitaxial layers by means of the partially filled waveguide method

We report the contactless determination of the conductivity, the mobility and the carrier concentration of II–VI semiconductors by means of the technique of the partially filled waveguide at a microwave frequency of 9 GHz. The samples are CdHgTe epitaxial layers, grown on CdZnTe substrates by molecular beam epitaxy. The conductivity is determined from the transmission coefficient of the sample in the partially filled waveguide. For the analysis of the experimental data, the complex transmission coefficient is calculated by a rigorous multi-mode matching procedure. By varying the conductivity of the sample, we obtain an optimum fit of the calculated data to the experimental results. Comparison with conductivity data determined by the van der Pauw method shows that our method allows to measure the conductivity with good accuracy. The behaviour of the transmission coefficient of the sample is discussed in dependence on the layer conductivity, the layer thickness and the dielectric constant of the substrate. The calculations require to consider in detail the distribution of the electromagnetic fields in the sample region. The usual assumption of a hardly disturbed TE₁₀ mode cannot be used in our case. By applying a magnetic field in extraordinary Voigt configuration, galvanomagnetic measurements have been carried out which yield the mobility and thus the carrier concentration. These results are also in good agreement with van der Pauw transport measurements.     

Tees on partially filled rectangular waveguides

We propose an analytical solution of the problem of determination of external parameters of T-shaped E and H tees on partially filled rectangular waveguides. The solution is tested for a particular case of E and H tees on hollow rectangular waveguides and compared with the known solution obtained by the numerical method. Calculated results show good agreement. Numeral results are given for tees on partially filled rectangular waveguides.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 7, pp. 901–909, July, 1996.     

Guided modes in a rectangular waveguide filled with single-negative materials

Based on classical electromagnetic theory, characteristics of guided modes in a rectangular waveguide filled with a pair of single-negative layers are studied. The results show that only surface waves of TE mode can propagate in this peculiar waveguide, no TM mode in any forms can propagate in it. In addition, TE waveguide modes will be affected by permeability ratio μ₁/μ₂ and dielectric layer thickness ratio P. Finally, from the electric field distribution of TE mode, we find the amplitude and location of the electric field can be adjusted by changing the thickness ratio P.     

Coupling frequencies of rectangular waveguide-dielectric resonators partially filled with dielectric

The partial-region method is employed to solve the problem of quasinatural mode H_n0(p+) of coupled waveguide-dielectric resonators with axially and centrally symmetric placement of inserts in an overmoded waveguide. Good agreement is obtained between the calculated and experimental results. The dynamics of coupling-frequency behavior is studied.Khar'kov State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 35, Nos. 3, 4, pp. 356–362, March–April, 1992.     

Propagation characteristics of a circular waveguide filled with a chiroferrite medium

A chiroferrite is made from chiral objects immersed in a magnetically biased ferrite. A waveguide including a chiroferrite is anticipated to possess some novel features due to the presence of chirality in combination with anisotropy. In this paper, the propagation characteristics of a circular metal waveguide filled with a chiroferrite medium are investigated by an analytical procedure. The equations of relations between the transverse components and the longitudinal ones of electromagnetic fields in general chiroferrite waveguides are derived in a cylindrical coordinate system. The coupled wave equations for the longitudinal electric and magnetic fields are decoupled into two Helmholtz equations which are then solved analytically. The characteristic equation is formulated for the circular chiroferrite waveguide. Propagation constants varying with the structural and material parameters have been calculated for several lower chiral modes. A number of interesting features have been revealed by the numerical results.