最新刊期
卷 ， 期 12 ， 1997
- 摘要：Based on differential geometry,the mutual admittance betWeen rectangUlar slot antennas on ageneral ellipsoid is presented by applying the geodesic constant method and UTD formulas and the numerical re.suits are obtained.关键词：Ellipsoid;Uniform theory of diffraction;Deodesic constant method;Mutual admittance2|34|0更新时间：2025-12-08
- 摘要：The Colton-Monk method for treating inverse electromagnetic and acoustic problems is brieflyintroduced and extended from the case of two-dimensional starlike object to the case of non-starlike object. Themore general parameterization of the contour of the scatterer is applied to arbitrary smooth object. Computer simulahon results demonstrate that the modified method is effective and reveal the relationship between the reconstruction effect of this method and the frequency of the used elecbomagnetic waves.关键词：Inverse electromagnetic problem;Contour reconstruction of non-starlike object;Cotion-Monkmethod2|21|0更新时间：2025-12-08
- 摘要：The Distorted Born Iterative Method（DBIM） is applied to deal with the nonlinear inversionproblem of the conductivity distribution in a two-dimensional axisymmetric medium. It is well known that the inversion of such transverse magnetic（TM） measurements is much more nonlinear than that Of transverse electric（TE） measurements. Tikhonov’s regUlarization method is used tO overcome ill-condition feature Of the mathe equation resulted from discretizing the nonlinear interal eqUation. Then the conjugate-gradient（CG） method isused to solve the matrix equation. In each iteration of foe DBIM, an efficient half analytical-half numericalmethod is used to solve the forward problem. This method provides a semianalytic expression for the Green’sfunction and its partial derivatives required in the inversion, and then deduces a semianalytic expression of theintegration in the nonlinear integral equation. Therefore, the efficiency and accuracy are improved dramatically.关键词：位场反演、变形玻恩迭代;格林函数;数值模式匹配4|94|12更新时间：2025-12-08
- 摘要：In this paper, a textural detector based on 2D Gabor function and visual textural perception isestablished first. then based on the textural detector and recent developed theory of time-scale space decomposition, a general class extending wavelet transform, an energy distribution based mtlltiscale texture analysis methodis proposed. The multiscale texture analysis techniqUe gives textural energy representation between spatial spaceand scale space, and provides a hierarchical analysis framework for image texture. They can detect different scaletexture features, correspond to the visual texture perception , and have the ability to recognize texture image effectively.关键词：纹理;纹理分析;特征融会．多尺度分解;能量分布．2DGabor函数2|145|10更新时间：2025-12-08
- 摘要：Introducing modern coneal theory, we present the netWOrk dynamic eqUations tO describe thenetwork states in nonsational’y environment in data communication netWorks with the objective of minimax the total network delay that is given by the packets waiting in all node bibers and ones are Processing in all networknodes. Based on the I’yapunov principle, we develop a new method tO test stability Of routing decision in datanetworks after the network nonlinear state control models are approximate lineallzed by numetical method. In thestationary network environment we cochrm the conclusions of netWork optimization control such as we can getshortest commllnication path that is defined as function of link delay,and optimal routing will never form a routing link ring and so on.关键词：Data communication network;Optimization control;stability2|81|1更新时间：2025-12-08
- 摘要：The computer simulation of microwave imaging of ideal dielectric cylinder was considered inthis paper. By volume equivalence princiPle, a system of integral equations was obtained. They link the media’spermittivity with scattering field and total field. The direct scattering problem can be solved from them. At thesame time, the inversion equation was got after taking variation on these integral equations. The inversion equation was transformed into a matrix equation after using the Moment Method. Some examples of inversion werepresented .The effect of random noise was also investigsted in this paper. What’s more, the inversion using incomplete scattering information was discussed.关键词：microwave imaging;VolUme equivalence Principle;Variation principle;noise;Incompletescattering information2|82|6更新时间：2025-12-08
- 摘要：The electromagnetic reflecting characteristics of a plane wave incident on an infinite stratifiedchiral medium coated on metal are investigated by using Wave-Splitting Method in freqUency domain, a newlydeveloped method for computation of electromagnetic fields. Forward-and backward-going modes are identified byapplying physical and mathematical transformation on Plane wave so that the propagating characteristics of electromagnetic wave in chiral media are shown clearly. Some useful conclusions are obtained through deduction andcomputation, which provide theoretical guidance for designing anti-scattering coating.关键词：Wave-Splitting method in frequency domain;Chiral media;Chirality2|52|0更新时间：2025-12-08
- 摘要：A physical model and a method for analysing and calculating the distributive capacitances andthe resonant freqUencies of the spiral resonators are described. First, the charge distributions on the spirals arefound by the moment method. Then the distributive capacitances of the spiral resonators are calculated. Theequivalent inductances of spiral resonators are then evaluated according to Grover’s formula, and the resonantfrequencies are finally computed .The calculated results agree well with the experimental data.关键词：Microwave resonstors;Spiral resonators;Planar Spiral resonators2|76|0更新时间：2025-12-08
- 摘要：Abstract: Based on modal field expansion techniqUes, the rf field structares of complex cavity withabrupt iran$1tions in gyrotrons are systematically studied, and the influences of TM type spurious modes are takeninto account. Many factors and changes which affect the resonant freqUencies, Q factors and axial field Profilesare also inveshgatedKeywoads: Waveguide step, Complex cavity, Modal field match,关键词：波导突变;复合腔;模式场匹配;回族管4|118|20更新时间：2025-12-08
- 摘要：A versatile numerical method is presented tO analyze all type of the E-Plane filters. A CADpackage is developed under Microsoft Windows based on this method. By using this package, various E-planefilters including the new E-Plane ones are analyzed. The numerical results apec well with the published andexperimental data.关键词：waveguide filter;E-plane filter;CAD software package2|173|12更新时间：2025-12-08
- 摘要：The propagation properties of cyclotron waves in relativistically moving magnetized plasma andthe reflection enhancements of cyclotron waves from magnetized relativistic electron beam front are researched.The reflection and transmission coefficients, the dispersion relahons and freqUency relations of cyclotron wavesare derived.The dispersion and propagation properties of transmission waves （R wave and L wave） are discussed,the enhancement of these reflection waves and the incident frequency regions Of total reflection are obtained.关键词：Cyclotron wave;Moving magnetized plasma;Relativistic electron beam front;dispersion relation;Reflection enhancement2|29|0更新时间：2025-12-08
- 摘要：A full wave spectral domain analysis of microstrip antennas by wavelet expansion method ispresented. The formulae for the wavelet analysis of moment method for the patch induced current distribution arededuced. A numerical example for a rectangUlar microstrip patch antenna is Provided, and the numerical resultsare compared with previous data with good agreement.关键词：wavelet analysis;microstrip antenna;Full wave spectral domain analysis2|98|2更新时间：2025-12-08
- 摘要：The dynamics theory is utilized in the analysis of target’s polarization scattering characteristicin the wide-band polarimetric case. A new conception of polarization spectrUm is Presented. Target’s signatureprocessing and recognition are investigated on the basis of polarization spectrum.关键词：high-resolution;local optimal polarization;Polarization spectrUm;radar target recognition2|179|16更新时间：2025-12-08
- 摘要：A new phsical model, Coaxial Resonator Tranverse Virtual Cathode Oscillator without appliedmagnetic field has been proPOsed in this paper. By means Of particle-in-cell simulation method its characterswere investigated. We defined a new concept-starting cnt density which will cause the stable oscillatingin the paper. A relationship between the oscillating freqUency and injected cnt density etc. are obtainedthrough simulation. We also analyzed two cases: the relativistic electron beam is injected from inner conductorand from outer conductor.The effect on virtual cathode oscillation was first taken into consideration with energyspread of the electron beam. The simulation results indicate that the new physical model has many advantages forpractical application.关键词：Virtual cathode oscillator;PIC simulation;Energy spread2|56|4更新时间：2025-12-08
- 摘要：The periodic strUctures are analyzed by a method in which the edge-element analysis is combined with the mode-matching method and the multimode-network theory. As tWO examples, the NRD gUide Periodic strUctUre and the image line periodic strUcture are calculated with the present method. The numerical resultsindicate that the present approach can be effectively used in analysis for the periodic structares with higher computation accuracy and efficiency.关键词：periodic structure;Edge-element;Mode-matching;Multimode-network2|87|1更新时间：2025-12-08
- 摘要：In order to make the detector perform robustly, an intuitive solution can be obtained by censoring the clutter observations from large and small deviations. In recent studies, censoring techniques have beenimplemented using order statistics （OS） and trimmed mean （TM） methods. In order to ultilize censored data, wepresent a quasi-best weighted （QBW） order statistics method resulting in an improved detection performancewhile censoring outliers. Based on quasi-best weighted method, a new greatest selection detector （QBWGO-CFAR） is proposed in this paper. Both Of its leading and lagging windows use QBW method to create twO localnoise power estimations , the greatest is selected as a globle estimation to set an adaptive threshold. Under the assumption of Swerling Ⅱ target and Rayleigh distributed clutter, the analytic expressions of Pfa, Pd,ADT and thepeak of false alarm at clutter edges are derived. The analytic results show that an improved performance overGOSGO or OSGO is obtained both in homogeneous background and in nonhomogeneous environment caused bystrong interfering targets and clutter edges. In specific cases. QBWGO-CFAR reduces tO GO and MX-CMLD.关键词：radar;detection;CFAR;Ordered statistics2|121|13更新时间：2025-12-08
- 摘要：A SAW passive sensor and remote sensing system are designed and researched. Through experiments, it is Proved that the design of the sensor and system is completely feasible. It not only has high sensitivity but also can be used for some special environments where the general sensors are useless. So this kind ofsensor and system has grest applicstion prospect.关键词：SAW;sensor;Remote sensing2|257|34更新时间：2025-12-08
- 摘要：The phase measurement equipment of Pulses modulated wave （or continuous wave） for microwave tube amplifiers is described. The computer controlling is adopted in equipment, the phase resolution isbetter than 0. 5° and the phase eder is within ±3° in the freqUency range from 8. 9GHz to 11.1GHz and phaserange from 0° to 360°.关键词：Microwave. Pluse modulated wave;Program control;Phase measurement2|36|0更新时间：2025-12-08
- 摘要：第八届全国毫米波亚毫米波学术会议召开在十一个分会共同努力下，由微波分会、电子部五十所、上海亚美微波仪器厂、电子部二十三所及总参五十七所上海处的积极筹备下，第八届全国毫米波亚毫米波学术会议于１９９７年９月ＺＩ日至２６日分别在上海和普陀山举行．出席会议的...1|27|0更新时间：2025-12-08
- 摘要：The dynamic action of the second harmonic and third coupled waves in lossy nonlinear medium is studied. Under the condition of equal-impendence and phase-matching, the analytic solutions of the wavesare obtained. If the condition is not satisfied I in some cases, the chaotic phenomenon is discovered by the calculation of Lyapunov exponents.关键词：Nonlinear medium;Coupled wave;chaos4|34|0更新时间：2025-12-08
- 摘要：《电子新产品新技术成果汇编》总第１０卷出版由中国电子学会编辑的《电子新产品新技术成果汇编（总第１０卷）》已于１９９７年１１月１０日出版发行．该汇编共收录了十大类２２５项最新成果，这些成果适用于工农业等各个方面，具有良好的市场前景．该汇编是广大企事业单...0|13|0更新时间：2025-12-08
- 摘要：A radar signal is researched, which is the random pulse position modulation sequence. Theexpression of its ambigUity function is presented. When modulating parameter is changed, the influence on resultsis analyzed,when the selections of the parameter are appropriate I its ambiguity function is approximate"thumbtack"form. So this signal is one of the best radar signals.关键词：Noise radar;stochastic signal;Anti-jamming system;Random pulse position modulation;average ambiguity function2|184|11更新时间：2025-12-08
- 摘要：In this paper, the reachability Gramian K, observability Gramian W and noise Gramian WN of2-D systems are extended to multidimensional （n-D） multi-input multi-output （MIMO） digital systems. An exPlicit relationship betWeen W and WN is derived. It is shown that: （1） for general n-D systems, the Gramians Kand WN satisfy a pair of modified discrete-time Lyapunov matrix equations （DTLME）; （2） for the causal recursive separable denominator （CRSD） n-D systems,both K and WN are block-diagonal matrices, and they can becomputed by solving n pairs of DTLME.关键词：Multidimensional digital systems;Multi-input multi-output systems;Lyapunov matrix equation;Gramians2|121|0更新时间：2025-12-08
- 摘要：The object of this paper is to investigate the parameters estimation of nonlinear autoregnssor（NAR） predictor. From the view point of adaptive infinite impulse response （IIR） filtering output error algoritlun,the NAR parameters estimation is investigated. With the help of the time averaging convergence condition, a new parameters estimate algorithm is Presented, which converges to a globally unbiased solution even ifthe additive noise exists.关键词：Nonlinear autoregressor predictor;parameters estimation;Unbiased solution2|135|1更新时间：2025-12-08
- 摘要：In this paper, the distorted Born iterative method is used to solve two-dimensional inverse scattering problems.This method Provides an iterative algorithm with faster convergence for inversion and imagingproblem. ’The inversion is performed for conductivity of tWo-dimensional axisymmetrically inhomogeneous medium, by using measurements on the symmetry axis at 20 kHz. The nonlinear integral equation for unknown conductivity distribution is first given, and is linearized by using Born approximahon. Then the Tikhonov regularization method is used to derive the conductivity distribution. In iteration procedure, the numerical mode matchingmethod is used to solve the forward problem. It is shown from the inversion results that the good imaging resultcan be obtained from simple field measurements at the axis points.关键词：Distorted Born iterative method;inverse scattering;Numerical mode matching method2|156|14更新时间：2025-12-08
- 摘要：The finite difference bine-domain method is extended to analyze an active antenna. The Procedures which are necessary to produce a stable algorithm are described. Because the large signal characteristic ofactive devices is introduced into the algorithm, it can calculate the transient electromagnetic field effectively.Some results are given and a comparison is made with the data obtained from piecewise harmonic balancemethod and the measurement.关键词：finite difference time-domain;active antenna;transient electromagnetic field2|138|1更新时间：2025-12-08
- 摘要：By applying the extended moment method, the broad-band characteristics of rotationally symmetric monopole antennas have been analyzed, and the optimum angle Of the cone is obtained. In this paper, thefigUres of the low-cut frequence versus height, width and volume of the antenna are shown, and the effects ofheight and width on the antenna gain have been discussed also. These offer the theoretical evidence for the Practical design. Theoretical calculations and experimental results are compared with excellent agreement.关键词：Ratationally symmetric;broad-band;antenna;gain2|92|8更新时间：2025-12-08
- 摘要：In this paper some studying results of the magnetic field distribution of an electromagneticalsextupole applying to a system for correction of spherical aberration in round electron lens are described. Measurement data of the magnetic induction in every coordinates in the sextupole and thier approximate formulas forideal and practical sextupole are given by combining experimental measurements and theoretical analyses. Themagnetic field distribution at the edge of the sextupole is discussed in more detail.关键词：Electromagnetical sextupole;Magnetic induction;Edge effect2|73|0更新时间：2025-12-08
- 摘要：A new method of distance measuring-lead-lag pulsc synthetie for sparse-array Syntheticimpulse and Aperture Radar （SIAR） is precented. The way for the distance difference-sum channel formulationand the error signal extraction is described. The effect of errors in angle measuring on distance measuring is discussed. Computer simulation results show this method is effective.关键词：Sparse array;synthetic impulse and aperture radar;Distance measuring2|164|9更新时间：2025-12-08
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