最新刊期
卷 ， 期 3 ， 1993
- 摘要：This paper shows that even if the human body is at the same electromagnetic environment, the absorption of EM energy for different posture of man model is different. A heterogeneous block sitting posture model is built up based on the standing posture model of the human body. The absorption of EM energy for the man model has been calculated by using the finite-difference timedomain method. The results show that in the electromagnetic dosimetry it is important to consider the posture of the man model.关键词：Finite-difference time domain method;Electromagnetic model of the human body with sitting posture;Electromagnetic dosimetry2|80|1更新时间：2025-12-08
- 摘要：Single-particle analysis of the electromagnetic free-electron laser（EM-FEL） sideband instability for primary wave with constant phase is presented in the paper. The dispersion equation is derrived, the oscillation frequency and linear growth rate of sideband instability are given. Detailed discussion is carried out and some important conclusions are drawn.关键词：Sideband instability;EM-FEL;Dispersion equation;Growth rate2|36|2更新时间：2025-12-08
- 摘要：Starting from Maxwell’s Equations, integral formulae of coupling coefficients in circumferentially corrugated circular waveguides with diameter gradual changed are derived and the explicit formulae of corresponding coupling coefficients for different coupled modes are obtained.关键词：Diameter gradual change;Corrugated circular waveguide;Coupling coefficients for any coupled modes.2|84|4更新时间：2025-12-08
- 摘要：Based on the spectral-domain method and the method of lines, a-mixed technique for the analysis of three dimensional electromagnetic field boundary value problems is presented, the technique takes the advantages of less memory space, less computation time and no relative convergence problems. Numerical results for microstrip resonator and suspended microstrip resonantor are in good agreement with the experimental data, thereby the accuracy of the mixed technique is verified.关键词：electromagnetic field;numerical computation;Resonator;The spectral-domain method;The method of lines2|60|0更新时间：2025-12-08
- 摘要：It was discovered in calculation that jellium/slab model reduces the power of adsorbed atoms to attract the valence electrons. As a result, the computed minimum in work function-coverage curve by jellium/slab model is too low compared with the experiment, especially for Cs on Ir （001） system. In this paper, a jellium sphere/slab model is proposed. A star expanssion of charge density in jellium sphere-vacuum region is given. Finally, the examination on this model is carried out. The calculation shows that the effect of discrete charge distribution of adsorbed atoms gives a contribution about 0.4 eV and 0.8 eV to the work function for Cs on W（001） and Cs on Ir （001） system at the minimum respectively, which makes the computed values more closer to experimental ones.关键词：Jellium/slab model;Effect of discrete charge;LAPW method;Overlayer-substrate system2|54|0更新时间：2025-12-08
- 摘要：A generalized Finite-Difference Time-Domain algorithm established by Maxwells equations with conductivity and magnetic conductivity S is presented. The sizes of cell have both unequal and expansive ability in three axial directions by using the factors of proportionality and expansion, which smakes the algorithm have the ability of extensive application. In order to show the application of the method, three examples are given with satisfactory results.关键词：finite-difference time-domain;Modified Maxwell’s equation;Expanding grid;absorbing boundary condition2|134|3更新时间：2025-12-08
- 摘要：This paper presents a new non-adaptive quasi-optimal approach for temporal-spatial 2-D signal processing. A temporal canceller is used to cancell the mainlobe clutter which has the same direction as target, and a spatial canceller is used to cancell some side-lobe clutter which has the same Doppler frequency as target. Then the other clutter is filtrated by temporal and spatial filters. Compared with other approaches, this one involves the smallest computation, and makes real-time processing possible, while the system performance is proximally optimal.关键词：airborne radar;2-D signal processing;Optimal processor;clutter suppression2|61|1更新时间：2025-12-08
- 摘要：In the paper, the mechanism of radiated emission from a shielded cablecaused by the pigtail effect, is discussed and presented by treating the cable as equivalent transmission line and dipole antenna. It is observed that the radiated emission from PC computers is produced mainly by common mode current along the cable. The results of computation and measurement for the radiated emission are introduced, and shown in good agreement with theoretical analysis.关键词：TEMPEST;电磁兼容;电磁辐射与信息泄漏;辫接效应2|104|12更新时间：2025-12-08
- 摘要：The radiation and coupling of linear antennas in a circular waveguide are discussed by means of dyadic Green’s function, field transformation and reaction principle. The general formulas of electric intensity and mutual impedance are given. The waveguide is semi-infinite. The reflection cofficient at the terminal is Γ. Lengths, feeding points, and orientations of antennas in the waveguide are all arbitrary. As examples, expressions of mutual impedance for four specific cases are given and discussed.关键词：mutual impedance;Linear antenna;radiation;waveguide2|71|2更新时间：2025-12-08
- 摘要：In this paper, the analytical expression of the optimum weight vector in the adaptive antennas, taking into account the mutual coupling existing between elements, is derived by analyzing the eigenstructure of covariance matrix, and the mechanism of the performance degradation due to mutual coupling is investigated. Finally, an efficient method of mutual coupling compensation in adaptive antennas is proposed.关键词：Adaptive antennas;Weight vector;Mutual coupling existing between elements;Method of mutual coupling compensation.2|189|8更新时间：2025-12-08
- 摘要：This paper studies systematically the magnetic circuit of a dual period focussing system. Based on given model, the magnetic field distribution, the stray megnetic field and the relationship between the field distribution and the geometrical size of the circuit are obtained by both theoretical caculation and experimental measurement with satisfactory agreement. The results can meet the demand of engineering design.关键词：Dual period magnetic circuit;field distribution;Magnetic induction2|30|0更新时间：2025-12-08
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A Numerical Method of Solving the Third-Order Geometrical Aberration Equation in the Combined Fields
摘要：In this paper the concept for precisely solving the third-order geometrical aberration equation in combined fields, using the technology of functional approaching and numerical reiteration, is raised. This avoids the additional errors caused by approximate calculation in traditional electron- optics and makes the calculation of aberrations more precise. The conclusions given in this paper supply a dependable basis to the design work of electron-optics.关键词：Election-optics;aberration;Electron-beam lithography;Computer aided design （CAD）2|30|1更新时间：2025-12-08 - 摘要：The model of magnetostatic surface wave delay line based on non-planar ground structure is improved, and the quadratic recursive programming is adopted to optimize the device for the first time, thus a new way to design magnetostatic wave devices is offered.关键词：Non-planar ground;magnetostatic wave;optimum design2|14|1更新时间：2025-12-08
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Sensitivity Analysis of the Superresolution Algorithm Based on the Gram-Schmidt Orthogonality Method
摘要：This paper presents a superresolution algorithm. n the Gram-Schmidtorthogonality method, analyzes the sensitivity of the direction-of-arrival （DOA） of the algorithm to the gain and phase errors, and gives the numerical results of the sensitivity related with different number of elements and different element spacing about two sources. The results show that the algorithm in this paper is more insensitive to the gain and phase errors than the Maximum Likelihood Method （MLM） and MUSIC method in condition of small seperating angle and large number of elements.关键词：radar signal processing;Adaptive array;Superresolution algorithm2|67|1更新时间：2025-12-08 - 摘要：Due to the racing development of the Very Large Size Integrated Circuit （VLSIC） and its decreasing price annually, the cost of phase array radar is no longer a deadly obstacle for the designer or user. It can be sure that phase array radar and especially the solid state ones would be very cost effective in the complex situation in the 1090’s, and wide band phase array radar has advantages in its performance and suitable for many specific uses. In this paper, we separate the wide band into two categories: those need only use phase shifter as quasi-wide-band and those need use both phase shifter and real-time-delay-line as wide-band. We pointed out that quasi-wide-band has many advantages and therefore could be most properous radar system in the coming decade, and wide-band phase system would be only used in some limited special situations.关键词：radar;Wide-band;Phase array2|197|4更新时间：2025-12-08
- 摘要：The mutual coupling of ultralow sidelobe dipole phased arrays is carefully investigated in this paper. A method obtaining the mutual impedances between elements of dipole arrays is first presented by use of network definition. The compensation for mutual coupling using mutual impedances obtained here is discussed. The calculation results show that this compensation method is valid. The effect of mutual coupling upon current distribution on elements of arrays and upon the sidelobe level is also discussed in this paper. These provide theoretical basis for realizing ultralow sidelobe phased arrays.关键词：Ultralow sidelobe;phased arrays;Dipole arrays;mutual coupling;Mutual coupling compensation2|134|1更新时间：2025-12-08
- 摘要：In this paper, the wavefororms of electromagnetic waves excited by pulse currents and their changes with the distance along the axis are studied.关键词：Electromagnetic wave propagation;Transient electromagnetic wave;Electromagnetic missile2|114|3更新时间：2025-12-08
- 摘要：In this paper, the basic principle of the method of lines is extended to the research of dispersion characteristic of elliptical microstrip lines using modified boundary conditions. A dispersion characteristic equation is derived. The results of this method are in agreement with those calculated in qu-asi-TEM case in low frequency for confocal ellipses. At the same time, the dispersion characteristic curves of two kinds of special microstrip lines are given.关键词：The method of lines;dispersion characteristic;Elliptical microstrip lines2|36|0更新时间：2025-12-08
- 摘要：A new piezoelectric polyvinyidene fluoride （PVDF） composite hydrophone attached to the inside surface of cylinder is developed. This type of hydrophone is characterized by high sensitivity, low response to acceleration and can bear high pressure. In this paper the theoretical expressions are in agreement with measured results. The hydrophone made by this new method is more advantageous for application in towed arrays.关键词：Polyvinyidene fluoride;Hydrophone;high sensitivity;Bear high pressure2|124|1更新时间：2025-12-08
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