最新刊期
卷 ， 期 6 ， 1997
- 摘要：In this paper,the principle and basic method for the simulation of the dispersionand the coupling impedance are described in detail. Simulation procedure on the basis of MAFIAcode and frequency domain method is completed. After the comparison with the experimental results and another numerical calculation from Argus code,the errors in the dispersion are less than1%. Lastly,two mathematical fits are discussed,it is shown that Curnow equation fit is better.关键词：Coupled-cavity slow-wave structure;traveling wave tube;numerical simulation2|123|30更新时间：2025-12-08
- 摘要：Cherenkov radiation produced by a thin annular relativistic electron beam in aplasma-filled dielectric-lined waveguide is analysed by use of the self-consistent linear field theory considering the electron three-dimensional perturbation. The effect of the thin annular electronbeam on the beam-wave interaction is completely described by a jump condition. The dispersion equation and the simultaneous condition of the beam-wave interaction are derived. Finally, thegrowth rate of the wave is obtained,and the effect of the background plasma density and electronbeam radius on the growth of the wave are presented.关键词：Self-consistent;Linear field theory;Annular electron beam;plasma;Dielectric Cherenkov maser2|59|0更新时间：2025-12-08
- 摘要：This paper presents the method of complex ray direction determination, withwhich the trace of complex ray direction can be determined. And this method analyzes the scattering fields in space which are produced by the target for complex source beam in frequent domainand complex source pulsed beam in time domain. There is the same accuracy between this methodand the complex ray tracing method. Furthermore this method can reduce the unknown four-dimensional（4-D）variables of the latter to 2-D ones,and 2-D variables to l-D one. And this effecientmethod solves the problems that we face when using the complex ray poroxial approximationmethod. This paper also analyzes and calculates the scattering fields in space of conduct plate,conduct sphere and concave conduct half sphere shell for the 3-D vector complex source beam. The numerical results of this method completely agree with those of complex ray tracing method.关键词：Complex source beam;Complex source pulsed beam;Beam analysis;Complex ray direction determination;electromagnetic scattering2|47|0更新时间：2025-12-08
- 摘要：In this paper,we analyse the scattering of an electromagnetic wave with a centimetric wavelength by an object whose surface is irregular. The angular dependance of the intensityscattered is obtained in the framework of the eikonal picture. Using different types of surface ourresults show a correlation between the irregularities and the local maxima in the intensity spectrumand a systematic backscattering enhancement.关键词：Irregularly shaped object;Eikonal picture;electromagnetic scattering2|49|0更新时间：2025-12-08
- 摘要：The moment method of analysis of coupled inclined slotted array cutting in thenarrow wall of waveguide is given. The calculated and measured frequency responses of S matrix of2 models are compared,which are made up by identical 5 elements both of single slots and tightlycoupled slot pairs. The calculated and measured directional characteristics of a linear array with 68elements of single slots are also compared. The results indicate that the given methods are ratheraccurate,and it can be used to analyze the characteristics of long linear array and to be the foundation of optimization.关键词：Slotted array;Inclined slots cutting in the narrow wall of waveguide;moment method2|135|14更新时间：2025-12-08
- 摘要：A robust Dirction-of- Arrival（DOA） estimation algorithm for uniform linear arrayin fourth-order cumulants domain is presented. Emphasis is laid on the investigation of robustnessof the algorithm. The algorithm is based on the Toeplitz Approximation Method （TAM） applied tovirtual correlation elements provided by the spatial fourth-order cumulants. Analytical resultshows that the algorithm is tolerant to array uncertainties and insensitive to additive Gaussiannoise. The algorithm is also featured with virtual aperture extention （nearly twice the actual aperture ） so that the resolvability can be enhanced. Simulation experiments are included to validate theanalytical result and to illustrate the robustness of the algorithm.关键词：Direction-of Arrival（DOA） estimation;robustness;cumulant2|77|2更新时间：2025-12-08
- 摘要：Numerical computation of Fresnel function and Maliuzhinets function is a difficultand important problem in electromagnetic scattering by a wedge with impedance faces. In this paper,we employ the tanh transformation to successfully solve this problem. The comparison between our result and the precision values shows that the computing precision of our method is highand its speed is rapid.关键词：西北工业大学101研究所tanh变换;Fresnel函数;Maliuzhinets函数;电磁散射;数值计算2|33|1更新时间：2025-12-08
- 摘要：In this paper,the wave dispersion property in completely plasma-filled waveguidewith definite magnetic field is analyzed. A revised dispersion equation is derived and calculated. Anew division of wave modes is given. Compared with the old division,this new division is more suitable. Also,from the numerical calculation of the new dispersion equation,some errors in former results are corrected.关键词：Microwave;magnetized plasma;Dispersion equation;Cylindrical waveguide4|197|6更新时间：2025-12-08
- 摘要：Electromagnetic scattering from rough surface has been investigated in the pastyears. Periodic and random models are often used in modeling the rough surface. Recently,fractalgeometry is rapidly improved. It provides a new way to model the rough surface whose characteristics are long-range order and short-range disorder. Moreover,it can also be used to discribp deterimnistic function,random function or an appropriate blend of these two functions. In this paper,fractal function is used to model the rough surface for investigating the interaction of incident planewave and rough surface.关键词：EM scattering;Fractal structure;Kirchhoff approximation5|120|1更新时间：2025-12-08
- 摘要：This paper presents a spreading model of momentum pitch ratio. The influence ofthe momentum pitch ratio spreading on interactive efficiency of the gyrotron with AQCORAA isstudied by the digital computation. The main conclusions are as follows:When the oblique angle ofAQCORAA is small,the interactive mechanism is CARM’ and the influence of momentum pitchratio spreading on interactive efficiency is stronger. When the oblique angle of AQCORAA is closeto 90",the interactive mechanism is ECRM’ and the influence of momentum pitch ratio spreadingon interactive efficiency is weaker.关键词：AQCORAA;gyrotron;Momentum pitch ratio;Spreading;Interactive efficiency2|31|1更新时间：2025-12-08
- 摘要：The concrete expression of an approximate construction of the field comPOnentsfor the dominant mode in a earn-rectangular waveguide,the cut-off wavelength calculated by usingBoundary Element Method and the concrete functions to determine the uncertain exponent constant of the power function in field expression confirmed by using Variational Method are given atfirst. Assuming only dominant mode propagated,the formula of the resonant conductance for longitudinal slot cut in the curved face of the earn-rectangular waveguide is derived by using the equivalence principlelan actual example is presented and the result of calculation and measurement isquite satisfactory.关键词：Cam-rectangular waveguide;TE dominant mode field;slot antenna;Resonantconductance4|149|3更新时间：2025-12-08
- 摘要：For optimum detection of moderately fluctuating radar targets,an adaptive cluttersuppression algorithm of band filtering based on fast subspace decomposition is presented in thispaper. Owing to the adoption of the technique of fast subspace decomPOsition,the computationalrequirement of the algorithm is obviously decreased and is favorable to be implemented on realtime. By the combination of Least Nquares （LS） and Band Filtering techniques,clutter spectrum estimation is obtained first with good property,then the detection of targets in special Doppler scopeis carried out. By use of the algorithm, effective clutter suppression and targets detection areachieved in varying clutter background.关键词：Fast subspace decomposition;Band filtering;Adaptive clutter suppression;Convergence2|95|1更新时间：2025-12-08
- 摘要：This paper proposes that approximate wavelet transform and time-frequency analysis can be used to detect moving targets with uniform velocities in straight lines. The approximatewavelet transform does not only find out velocities in the square terms in phases of target signals,but also preprocess signals to delete most of background clutters and noises for the time-frequencyanalysis. The time-frequency analysis can find out velocities in both linear and square terms ofphases of signals.关键词：: Synthetic Aperture Radar （SAR ）;Detection of Moving targets;Approximatewavelet transform;time-frequency analysis2|146|7更新时间：2025-12-08
- 摘要：Traditional ISAR imaging is based on the uniform rotation of targets. The nonuniform rotation may occur to manoeuvring targets,which will produce smeared images. In this papera constant acceleratively rotating model is used instead of the traditional uniform rotating model.The imaging quality is improved by using the new method.关键词：ISAR;time-frequency distribution3|164|29更新时间：2025-12-08
- 摘要：In present paper the problem of calculating electron trajectories in an electrostaticfield is discussed. A set of formulae is given. Three-dimensional problems involving simple electrode configurations,for which the trajectories can be claculated analytically,are used. The resultsshow that the accuracy is hith enough and the algorithm is suitable for tracjectory calculation inasymmetric configuration.关键词：electrostatic field;Electron tracjectory;Computer aided-design;Accuracy;Asymmetric configuration2|83|1更新时间：2025-12-08
- 摘要：The B-spline finite element method in polar coordinates for solving some waveguide eigenvalue problems is described. The technique has two main advantages: （1）Avoiding thesubdivision errors at some curved boundaries 1 （2）Improvement on the computational accuracy for asharp corner existed in the waveguide cross section. The B-spline finite element equations in the 0p coordinate system are established. The method is used to solve the eigenvalue problems in circular,sector,double-ridged circular,and heart waveguides. The numerical results are compared withthe exact solutions and those obtained by the traditional finite element method in polar coodinates,which demonstrates that the present method is convenient to implement,and leads to a high computational accuracy and substantial saving in computer storage and time.关键词：极坐标;波导．本征值;B样条;有限元2|85|2更新时间：2025-12-08
- 摘要：For the purPOse of improving the DOA estimation Performance,we present a newiterative algorithm for estimating the DOA of multiple dappler signals by using both the signal’ Stemporal and spatial structures in the case of less snapshots and low SNR. In this Paper, a simplified algorithm is also presented to reduce the computation. These two algorithms outpefferm theconventional ML method which does not use the signal’ S temporal structure in the case mentionedabove. Monto-Carlo experiments illustrate the efficiency of proposed algorithms.关键词：maximum likelihood estimation;DOA;2-D parameter estimation;algorithm2|404|55更新时间：2025-12-08
- 摘要：In this papaer,equations for the computation of the surface impedance and attenuation coefficient of surface wave in a conductor-backed lossy dielectric sheet are presented. We propose that the product of μr and μr and the attenuation coefficient are the parameters evaluating thequality and effectiveness of the absorbing material respectively. Experimental results of the attenuation coefficient are presented. The experimental results are found to be within 1dB of the calculated value.关键词：Absorbing material;surface wave2|95|3更新时间：2025-12-08
- 摘要：On the basis of the difference of the patterns in two principal planes of a multimode pyramidal horn that are predicted by numerical method,the mode ratio is determined to be inthe range from 0. 68 to 3. 73. By means of solving a set of mode matching matrix equations,themode ratio and phase at a E-plane symmetrie step in a rectangular waveguide are accurately obtained. The usually used formula of propogation constant of an infinite extension taper rectangularwaveguide is revised so that the phase difference between TE10 and TE12/TM12 modes at the hornaperture can be predicted more reasonably. The results from theoretical calculation and experimentare compared,and the ways to broaden the band are discussed.关键词：Multimode pyramidal horn;Numerical method;Mode matching2|138|13更新时间：2025-12-08
- 摘要：According to the basic optimization principle of artificial neural networks,a Lagrange function based neural network modeling approach appropriate for general nonlinear programming is investigated. The control strategy to improve the neural computing efficiency is studied,such as nonlinear degree control strategy of neurons,Lagrange multiplier control strategy,etc.The feasibility and efficiency of the neural network and the control strategy advanced are verifiedwith tests.关键词：neural network;constrained optimization;neural computing2|77|7更新时间：2025-12-08
- 摘要：The parablic torns can be used to scan or make multiple beam on a plane or cone.But the aberrations on the aperture along the intermediate plane between the neutral plane and theperpendicular plane are so evident that the performance of the antenna may be lower. In this paper,using a new modified generatrix instead of parabola rotating round a bias axis,a new typetorns with better penformance has been established.关键词：New modified generatrix;Multiple beam;New torns rotating round a bias axis2|75|1更新时间：2025-12-08
- 摘要：This paper outlines the principles.calculating methods and functions of the CADsoftware for designing TWT’s PPM focusing system,which we developed. This software includesthe calculating programs,pre- and post-processing programs. The accuracy of the calculating pro-grams meets the demand of engineering design,and is a good CAD tool for developing the TWT’PPM focusing system.关键词：TWT;PPM focusing;Calculation program;CAD software2|63|9更新时间：2025-12-08
- 摘要：Suppose the Fourier transform converts functions of z to functions of the transform variable Y. When the Spectral Domain Method is used to calculate z component of magnetic （electric） field,which is induced by pulse magnetic （electric） current in z direction,it can’ t provide the field at some special points. When the field point has the same transverse coordinate with the source POint,the inverse Fourier transform is nonconvergent. When the source is triangle functionsine function etc.,the nonconvergent disappears. This paper supplies the proof of this point ofview.关键词：spectral domain method;Integral equation;pulse function;Nonconvergent2|80|0更新时间：2025-12-08
- 摘要：This paper solves an open problem in [5] that ψ（f,f2,f,f,f） is a super-pseudorandom permutation,proves that the permutation can resist O（260） -order chosen plaintexts -ciphertexts attack,and constructs the secure message authentication code by the known result.关键词：Pseudorandom permutation;Super-pseudorandom permutation;message authentication code2|31|0更新时间：2025-12-08
- 摘要：A new method for analyzing a millimeter H-plane waveguide circulator with a partial height ferrite post is presented. Based on the newly derived formulas,several broadband MMW waveguide circulators have been investigated,designed,assembled and tested. Good agreement between the analytically obtained performance and experimental results is observed.关键词：Ferrite application;Waveguide circulator;millimeter-wave2|163|4更新时间：2025-12-08
- 摘要：The Maximum Likelihood Estimation （MLE） processor can be used to measurethe altitude between ocean level and satellite platform. In this paper,the basic principle of MLE isreviewed. According to altitude measurement principle,the altitude estimation error is studied andthe relations among the altitude error,wave height and signal-to-noise ratio are tested and verified.关键词：Altitude error estimation;The maximum likelihood estimation;radar altimeter2|98|3更新时间：2025-12-08
- 摘要：In this paper,we present an adaptive weighted combination filter based on theopening and closing operators in mathematical morphology as well as the adaptive processingmethod.The filter is capable of effectively suppressing various additive white noise, and positive ornegative impulsive noise. Moreover,it does not blur the sharp step changes in the signals.关键词：mathematical morphology;adaptive filtering;Morphological filter2|344|42更新时间：2025-12-08
- 摘要：This paper proves that ordered statistic CFAR （OS-CFAR） detector is also ofCFAR under K-distributed clutter background,when the shape factor is known. The performanceof the detector is analyzed against uniform clutter background. The loss of SCR in the differentcase is studied. For unknown shape factor,a valiable method to estimate the shape factor is given.关键词：K-distributed clutter;ordered statistic;CFAR detector2|222|23更新时间：2025-12-08
- 摘要：This paper discussed the resonant loss dielectrical cavity used for matching terminals and severs in coupled cavity TWT, which has been put into practice in our research work. The methods of calculation and measurement for resonant frequency,dielectrical constant,quality factor and loss tangent of the varierty of dielectrical cavity were given. It has been verified in developing aC-band 50KW coupled-cavity TWT that the theoretical calculation data were in good agreementwith test results,so that the validity and feasibility of this analysis and measurement method wereshown.关键词：Resonant loss dielectrical cavity;Coupled-cavity TWT;Matching terminal2|91|26更新时间：2025-12-08
- 摘要：The remote sensing data of atmosphere and ground surveying by meteorologicalsatellite have widespread applications in social and economical development． The system that introduced by this paper can receive and process remote sensing data of all meteorologlcal satellites thatlaunched or will be launched． The spedal features of this system are smallslze，Intelllg6nt，multifunctional and portable.关键词：Meteorological satellite receiving;Antenna intelligent tracking;Applications of remote sensing information;Image processing2|70|1更新时间：2025-12-08
- 摘要：On the basis of the principle of FMCW radar,this paper applies new technology and miniature unit circuits at W-band,proposes an advanced front end at W-band. Volume of the front end is decreased greatly. Analog-data hybrid circuits are used. A high speed chip computer is applied to complete FM linearity closed-loop real-time calibration for VCO at W-band. Operatingfrequency of front ends is 94. SGHz,FM bandwidth 280MHz,FM linearity below 0. 2%,,transmitting POwer more than 5mW.关键词：millimeter wave;FMCW;radar;Linear calibration2|160|5更新时间：2025-12-08
- 摘要：应用生物分子材料（ＢＲ）的模式识别系统曹黄强（电子工业部电子科学研究院，北京１００８４６）视紫红质蛋白（ＢＲ－Ｂａｃｔｅｒｉｏｒｈｏｄｏｐｓｉｎ）存在于人或动物的视网膜细胞中．用生物工程方法制取的视紫红质蛋白具有很好的三阶光学非线性特性，是一种新颖的...2|45|0更新时间：2025-12-08
- 摘要：一种新型微波手术设备ＯｎａＮｏｖｅｌＭｉｃｒｏｗａｖｅＳｕｒｇｉｃａｌＯｐｅｒａｔｉｏｎａｌＩｎｓｔｒｕｍｅｎｔ￥／／刘健（西安理工大学自动化系，西安７１００４８）利用微波能的热效应实现外科手术止血的微波手术刀已经商品化，但微波泄瞩的防护问题没有满意...4|24|0更新时间：2025-12-08
- 摘要：金属－半导体金刚石薄膜的接触性质研究刘兴钊，杨邦朝，李言荣，贾宇明（电子科技大学．成都６１００５４）一、引言金刚石薄膜由于具有载流子饱和速率大、击穿电压高、介电常数低、热导率高等优异性能，被认为是大功率、高瞻及恶劣环境下使用的电子元件的理想材料．在金...2|103|0更新时间：2025-12-08
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