最新刊期
卷 ， 期 3 ， 1992
- 摘要：Electron optical aberration theory for angularly wide and transversely large electron beams in electromagnetic focusing systems with curvilinear axes has been further developed. By introducing a rotating curvilinear orthogonal coordinate system, the curved main trajectory equation, the first order curvilinaer paraxial trajectory equation and the first order ideal imaging properties have been discussed. By defining integration function, all second-order aberration coefficients have been expressed in compact form.关键词：electron optics;Electron lenses;Aberration of electron optical systems;Focusing of charged particles2|46|2更新时间：2025-12-08
- 摘要：A novel algorithm for optimal design of filter banks in MTD is presented. It can constrain frequency response of filter banks to form null at zero frequency point and to obtain minimum side lobe area. As contrasted with Remez design algorithm on condition of equal main lobe area, the average improvement factor of MTD system for ground clutter increases by about 4 dB. The optimal design algorithm has been applied to a practical radar MTD system and has provided satisfactory performance.关键词：MTD;filter banks;Window function;Improvement factor.2|255|2更新时间：2025-12-08
- 摘要：A pair of conjugate surface acoustic wave （SAW） dispersive filters with LiNbO3 is applied successfully in the pulse compression system for the first time in China. Hence, a series of Linear Frequency Modulation signals （Chirp） are coherently generated in the transmitter of Synthetic Aperture Radar （SAR） and the pulse compression is completed at IF stage of the SAR receiver. In the meantime, the Doppler phase information is remained. As compared with optical, CCD and digital processing, it takes some advantages and exhibits some distinguishing features of Chinese SAR system. In this paper, the design concept, the description of LFM pulse compression system and its experiment results are presented in detail. Finally, a sample of SAR image is given and the programme & technical line are verified.关键词：synthetic aperture radar;Imaging radar;pulse compression;linear frequency modulation;Range resolution2|50|1更新时间：2025-12-08
- 摘要：This paper presents a new structure EECRM. The electrostatic field and the R.F. field are discussed in detail. In our study, we find a new electron bunching mechanism. It is found out by computation that the efficiency of the energy transform in this system is higher than that in the coaxial EECRM.关键词：Angular-direction period;Electrostatic maser;Bunching;efficiency2|10|0更新时间：2025-12-08
- 摘要：This paper presents an efficient method of topology optimization for antenna structures. By the method, the optimal topological form can be obtained to satisfy the demand of its electronic performance. From the point of view about the topology optimization of trusses, not only the behavior constraints such as displacement and stress constraints could be dealt with during the optimal design but also the main difficulty of predetermined displacement field is warded off in this method. Finally, this method is applied to several examples of trusses and two types of antenna structures with excellently satisfactory results obtained.关键词：Antenna structures;Topology optimization;Structural form;linear programming2|162|2更新时间：2025-12-08
- 摘要：A new normalized S parameter method of measuring admittance of inclined slot antenna in the narrow wall of a rectangular waveguide is presented in this paper. Because attenuation and phase shift of measured waveguide section are deleted, we can obtain the conductance and susceptance of a slot accurately. The rightness of this method is examined by a close agreement between the theoretical and experimental results in S band. The error sources and the method of decreasing measurement error are described at last.关键词：slot antenna;Normalized S parameters method;Equivalent network;Admittance;Narrow wall of a rectangular waveguide2|99|7更新时间：2025-12-08
- 摘要：The calculation for the diffraction field of a steady-state quasi-optical resonator is a key problem to realize the integration of quasi-optical power combiner with antenna. In this paper, the diffraction field of a steady-state quasi-optical resonator has been calculated by combining complex source theory and complex ray theory with GTD. The far field patterns of diffraction field in E and H plane are given. These calculated results are verified by the experiment.关键词：Quasi-Optical cavity;Complex ray theory;Diffraction Field.2|56|0更新时间：2025-12-08
- 摘要：<正> 中国神经网络1991学术大会、第二届全国神经网络—信号处理学术会议暨中国科协电联神经网络委员会成立大会于1991年12月3日—6日在南京东南大学隆重举行,来自全国各地的专家、学者和教授共三百五十多人云集南京参加这一盛会,其中青年学者占据了大多数,这充分说明了我国神经网络研究欣欣向荣的大好形势。 本次联合会议共录用学术论文360多簏,精装论文集三本,内容涉及神经生理与生物神经网络模型、感觉感知与认知心理模型、神经网络与生物医学工程、视觉理论与机器视觉模型、人工神经网络模型、神经网2|15|1更新时间：2025-12-08
- 摘要：A new method for the analysis of electromagnetic wave scattering by an infinite plane metallic grating is presented in this paper, which is based on the method of lines and Floguet’s theorem. Numerical results are in good agreement with those by spectral domain method and experimental data. However, the method presented in this paper possesses the advantages of simplicity, less computation, etc. over previous methods.关键词：The method of lines;periodic structures;electromagnetic scattering;Metallic grating2|83|8更新时间：2025-12-08
- 摘要：A typical structure of microwave filter, i.e. rectangular waveguide inserted with cylindrical dielectric resonators has been developed. By applying mode-matching technique, the scattering characteristic of the resonator is accurately analysed. As a result, the network parameters and the resonant frequency are obtained. The theoretical results are in goo agreement with those of experiments. The significant effect of the substrate on choosing the resonant modes is also revealed in theory and experiments.关键词：介质谐振器、介质滤波器;截止波导;非截止波导2|106|1更新时间：2025-12-08
- 摘要：A continuous nonlinear technique （CNT） for instantaneous data is proposed in this paper. The technique is based on L2 space optimization instead of 12, so that both random noise and computational errors are reduced during the calculation process, and relatively stable resolutions are obtained. The superiority of CNT to the conventional nonlinear least square technique in the presence of random noise is demonstrated by simulation computations. Finally the program which uses CNT to determine the number of natural frequencies contained in the measured response is established.关键词：Pathosis problem;Continuous technique;Extraction of culmination6|64|2更新时间：2025-12-08
- 摘要：The kinetic properties of electrons capture in solid dielectrics under strong electric field are studied with surface potential measurement in this paper. The process of traps filling and the variation of maximum filling values with field are qualitatively explained with first-order trapping kinetic equation. Further analysis shows that in the range of strong field approaching breakdown value, the free electrons in conduction band will collide with the trapped electrons. Once the colliding ionization develops to some extent, electric breakdown occurs.关键词：Strong electrical field;Solid dielectrics;Trap filling kinetics4|157|1更新时间：2025-12-08
- 摘要：The 3-D self-consistent nonlinear theory of free-electron-laser amplifier is developed in this paper. Considering the variations of the radiation fields, electron beam and wi-ggler fields in three-dimensions, and neglecting both the self field of the beam and the space charge effects, we derived a set of nonlinear differential equations for the rectangular waveguide configuration with a bifilar helical tapered wiggler. According to numerical simulations, the efficiency can be enhanced obviously when the amplitudes or periods of the wiggler begin to decrease gradually at suitable points.关键词：Taper;Free-electron-laser;Self-consistent;Three-dimensions;nonlinear theory2|11|0更新时间：2025-12-08
- 摘要：The first experimental demonstration of tbe stimulated radiation from electrostatic electron cyclotron resonance masers （EECRM） using non-circular electron beam interacting with TEM-mode electromagnetic fields is reported in this paper. The voltage tuning curves of the radiation strength and operating harmonics of electron motion were determined. The experimental results agree with the theoretical results presented previously.关键词：Maser;Stimulation radiation;Cyclotron resonance2|19|1更新时间：2025-12-08
- 摘要：<正> 东南大学无线电工程系数字信号研究室开发的“通用图文档案管理系统”,“静止图象传输系统”,“通用图象与工程信号压缩软件包”以及该室与南京大桥机器厂联合研制的“一点多址全自动无线电话系统”等四项研究成果于1991年12月在南京通过江苏省科委的技术鉴定。 一点多址全自动无线电话系统 在吸取国内外6|27|0更新时间：2025-12-08
- 摘要：The full nonlinear analysis method is a new method for the microwave circuits under mul-titone excitation based on the spectral balance algorithm. In this paper, a new frequency-domain mixer diode model and an adaptable spectral balance algorithm are firstly proposed, and the full nonlinear analysis is performed in the frequency-domain for a microwave mixer driven by multi-tone signals. Some frequency-conversion performances of the mixer are investigated in detail.关键词：Nonlinear circuit;Microwave mixer;Full-nonlinear analysis2|100|1更新时间：2025-12-08
- 摘要：Propagation properties of slab dielectric chirowaveguide have been analysed first in this paper. The field distribution, dispersion relations and cut-off wavenumber equation are given, and the influences of chirality admittance ζc on lowest cut-off wavenumber kc are discussed. It is shown that TE, TM and TEM modes cannot be supported in slab dielectric chirowaveguide. If ζc→0, the results in this paper are all turned into general slab dielectric waveguide’s.关键词：Chiral medium;Chirality admittance;Chirowaveguide2|83|7更新时间：2025-12-08
- 摘要：In this paper, the inherent relation between the window function （WF） of digital signal processing and the tapered transmission line（TTL） of microwave engineering is revealed. Some high quality WFs are used for TTL design. The design priniciple is offered and the design formulas are derived.关键词：Window function;digital signal processing;Tapered transmisson line2|406|4更新时间：2025-12-08
- 摘要：In this paper, an angle-resolved microwave coherent scattering system is described. Dielectric beam splitter was employed in this system, which facilitates the scan of scattering angle. The dispersion relation of ion acoustic wave and the wavenumber resolution of the system have been measured by using this system. It is shown that the system is very suitable for studying long-wavelength electrostatic waves and instabilities in plasma.关键词：microwave scattering;Plasma diagnose;Ion acoustic wave4|72|2更新时间：2025-12-08
- 摘要：By combining the conformal mapping with variational method, the resonance frequencies of a y-shaped and demagnetized ferrite junction are derived. The change of impedances of each section of a switch is also obtained. Calculations applying above approach to X and Ka band switches are verified by experiments.关键词：ferrite;Latching switch;conformal mapping;Variational method2|31|1更新时间：2025-12-08
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