最新刊期
卷 ， 期 12 ， 1994
- 摘要：Edge-element method is a new kind of calculation method based on the mesh of finite elements. Compared with the traditional finite-element method（nodal elements）, it has advantages of less variables and computing time（and storage） without distribution of spurious modes. In this paper the edge-element formulae for 3-D electromagnetic problems based on tetrahedra and calculation results for inhomogeneously filled rectangular cavities are presented. New forrmulae are also presented to allow quantitative comparison between the global matrices that arise from the alternative edge and nodal elements. The origin of zero eigenvalues and prediction of their total number are discussed with newly proposed forrmulae. Therefore this new method has been theoretically enriched and developed by this paper.关键词：Computational electromagnetics;Finite elements;Edge elements;3-D electromagnetic problems2|168|25更新时间：2025-12-08
- 摘要：The expressions of the characteristic impedance of three new kinds of transmission lines-elliptic cone stripline,microstrip line and coaxial line are derived. The formulas are based on the TEM or quasi TEM modes assumption. The sphero-conal coordinate system can be transformed into plane coordinate system. With the aid of the known results fcr stripline and microstrip line,the characteristic impedance,of this three kinds of transmission lines are obtained.关键词：elliptic cone stripline;Elliptic cone microstrip line;Elliptic cone coaxial line;Sphero-conal ccordinate;characteristic impedance2|90|1更新时间：2025-12-08
- 摘要：The application of the new nonlinear optimization algorithm to antenna array design is demonstrated by low sidelobe pattern optimization synthesis of axial dipole arrays on cylindrical surfaces. By use of realized gain patterns（RGP） of array elements, we formulate array synthesis as a nonlinearly constrained optimization problem, and use a new direct method to solve this problem. The technique allows one to find a set of array coefficients that yield a pattern meeting a specified sidelobe level with the maximum directivity,if such a set of array coefficients exists. If the specifications cannot be met,the technique will result in a set of array coefficients that yield a pattern meeting the best attainable sidelobe level and having the directivity as high as possible. Also,some numerical results for low sidelobe pattern synthesis are given.关键词：Axial dipole array;low sidelobe;directivity;Optimization synthesis2|84|1更新时间：2025-12-08
- 摘要：A numerical method for calculating the resonant frequency of multi-dielectric covered microstrip antennas by means of spectral domain immittance approach is described. Two specific method of numerical integrals are proposed to deal with the chief difficulty. A rectangular patch has been fabricated and measured. The numerical results of resonant frequency are in good agreement with experimental data. Some useful conclusions have also been obtained.关键词：microstrip antennas;Layered superstrate;Spectral domain immittance approach;Oscillatory infinite double integral3|238|4更新时间：2025-12-08
- 摘要：This paper presents some problems in the design of ultralow sidelobe phased arrays, which concerns a lot of factors. We mainly discuss problems such as element coupling in array ,transforming parts between element and feed line, errors of illumination and element location,and the calibration of elemental channels.关键词：Ultralow sidelobe;Element mutual couplng;Analysis of errors;Calibration of elemental channels2|477|24更新时间：2025-12-08
- 摘要：In this paper,a frequency-domain harmonic balance method of nonlinear microwave circuits is discussed in detail. The establishment of equations,the character of Jacobian martix and the arithmetic operator method are presented.关键词：nonlinear microwave circuit;Harmonic balance analysis2|211|9更新时间：2025-12-08
- 摘要：This paper investigates the effect of reflector surface distortion on the antenna radiation pattern,and gives some reasonable criteria for reflector antenna structure design.关键词：Mechano-electrical unification;Reflector;Radiation pattern;Distortion2|229|23更新时间：2025-12-08
- 摘要：In this paper,a new method of analyzing millimeter wave harmonic oscillators via Volterra series and the nonlinear transfer function theory is presented and determining equations characterizing nonlinearity of the oscillators are given. By solving a set of nonlinear algebraic equations, the oscillation amplitudes and frequencies of the harmonic oscillators are calculated. Analysis example is given and compared with the analysis results of the harmonic balance method（HBM） and so on. The result shows this method has the features of rigorous theory,a high accuracy,a wide range of application and so on. Especially,using the results of the first-order determining equations as the initial values of other methods of nonlinear numerical analysis,the computation time can be greatly reduced and the higher accuracy can be achieved easily.关键词：Volterra series;Transfer function;Determining equation;Volterra kernel2|63|1更新时间：2025-12-08
- 摘要：The fields in continuously curved waveguides of rectangular cross section are represented in terms of the exact eigenmodes. The formulas and numerical methods for computing Bessel functions of imaginary orders are presented,and the problem of computing eigenmodes and their angular propagation constants in curved waveguides of arbitrary curvature with high precision,is therefore completely solved. Typical numerical results are given. It is shown that there is a one-to-one correspondence between the eigenmodes in curved guide and the corresponding modes in staight guide, and that the equivalent propagation constants for curved guide close numerically to the propagation constants for staight guide,while the radial distribution of the modal fields is in an attenuated standing-wave form.关键词：Waveguide bends;Eigenmodes;Bessel function;Bessel function of imaginary order;Asymptotic expansion2|174|4更新时间：2025-12-08
- 摘要：Based on the theory of coupled vibration,the paper studied the coupling vibration modes of resonant vibration in finite diniension PZT piezoelectric ceramics disks. The relation between the radial vibration and the thickness vibration of the disks was analyzed. The frequency equation was derived theoretically. These results agree well with those of traditional theory such as the numerical methods. Experiments show that the calculated resonant frequencies are closer to the measured results compared with the results of one-dimensional vibration theory.关键词：Coupled vibration;resonant frequency;Equivalent elastic constant;radial vibration;Thickness vibration2|526|23更新时间：2025-12-08
- 摘要：The picosecond photoconductive switches are described and developed. The experimental results are given to show the wave form of the photoconductive switches responsing to the pulse laser. This new type of pulse sources can be used as the radiation source of the novel ultrawide band（UWB） radar.关键词：Picosecond optical electronics;Photoconductive switch;Photoconductivity;Ultrawide band radar2|201|16更新时间：2025-12-08
- 摘要：A mixed technique of moment method（MoM）,conjugate gradient method（CGM） and fast Fourier transform（FFT） is presented to deal with the electromagnetic scattering of cylinders,which have arbitrary cross-sections and are composed of conductor or inhomogeneors dielectric. This methed is based on collocation technique in which eqnivalent current is considered as unknown function. CGM and FFT technique are used for reducing storage and CPU time, therefore electrically large cylinders of abitrary cross-sections and imhomogeneous permittivity can be handled simply and effectively. The numerical results for dielectric rectangular cylinder,circular and conducting cylinder are in agreement with classic results or results given in other papers.关键词：electromagnetic scattering;Cylinder;Mom;CGM;FFT2|118|7更新时间：2025-12-08
- 摘要：The complex images of a point charge in rectangular conducting planes are nvestigated. Further research has shown that only a few complex images are used to replace the infinite real images, but the error is small when they are utilized to compute the electrostatic potential functions.关键词：Complex image;Rectangular conducting planes;electrostatic field2|95|2更新时间：2025-12-08
- 摘要：By combining the concept of "two-exterior spaces"with the common T-matrix formulation, the modified T-matrix formulation of a scatterer is derived. As an example of application, the problem of multiple scattering of EM waves by a half-space of randomly distributed dielectric spheres is analyzed by using the modified T-matrix formulas of a sphere. A transcendental equation for determining the effective wavenumber of the random medium is obtained under Foldy’s approximation. The numerical results in the low-frequency limit show that the modified Tmatrix approach with Foldy’s approximation is only applicable for the sparse distribution of the scatterers. As the distribution of the scatterers is dense,the quasicrystalline approximation together with the pair distribution function of the scatterers has to be used.关键词：Modified T-matrix;Randomly Distributed Scatterers;Multiple Scattering4|87|0更新时间：2025-12-08
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A New Method to Calculate the Admittance of Arbitrary Inductive Diaphragms in Rectangular Waveguides
摘要：计算矩形波导中任意感性膜片电纳的新方法ＡＮｅｗＭｅｔｈｏｄｔｏＣａｌｃｕｌａｔｅｔｈｅＡｄｍｉｔｔａｎｃｅｏｆＡｒｂｉｔｒａｒｙＩｎｄｕｃｔｉｖｅＤｉａｐｈｒａｇｍｓｉｎＲｅｃｔａｎｇｕｌａｒＷａｖｅｇｕｉｄｅｓ￥／／唐敬贤，黄卡玛，刘永清，曾祥德，...2|120|4更新时间：2025-12-08 - 摘要：The application of dynamic programming method to the design of optimum thinned arrays is described firstly,then a new method of dynamic programming with partioned preprocessing for reducing peak sidelobe level is presented. Two examples are given using DPP to demonstrate its performance. Finally,several "optimal" arrays are compared,showing that DPP has superior advantages.关键词：Antenna arrays;Thinned array;array processing;signal processing;optimum arrays2|250|40更新时间：2025-12-08
- 摘要：In this paper is studied the effect of electron beam geometrical deforniation on the small signal properties of TE mode Electron Cyclotron Resonance Maser（ECRM）, based on the elliptically cross-sectional e-beam deformation model. As an example,the effect of some small beam deformation errors on the TE mode fundamental ECRM coupling coefficient is quantitatively shown.关键词：Electron beam geometrical deformation error;Elliptically cross-sectional beam;ECRM;Coupling coefficient2|23|0更新时间：2025-12-08
- 摘要：The detecting method which is stipulated by State Standard of China（GB8056-87） is not effective in such a case that many outlying observations appear at the same side in the exponential sample. To conquer this shortcoming,a new detecting method is proposed. The distribution density function of the new test statistics is obtained.关键词：Outlying observation;Exponential distribution;Test statistic;Sample;robustness2|138|14更新时间：2025-12-08
- 摘要：国际学术会议名称、组织机构及其功能浅释周孟奇（中国电子学会，北京１０００３６）随着我国科研和学术水平的不断提高，我国学者和科研人员出国参加国际会议的机会和人数在不断增加。同时，也吸引了相当多的具有国际水平的学术会议在华召开。为了便于我国学者和科研人员...2|196|0更新时间：2025-12-08
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