最新刊期
卷 ， 期 6 ， 1995
- 摘要：The design of offset feed shaped compact antenna test range is studied systematically. A new method of the geometrical optical synthesis of dual offset shaped reflector antenna is developed. This method can be easily understood and developed,and used in numerical calculation. A new technique used to calculate the cross polarization of compact antenna range is also developed. Several universal conclusions are obtained for cross polarization. At last,the contradiction between cross polarization and diffraction,an important problem in the design of shaped compact antenna range, is discussed.Then the significance of antenna configuration optimization is clarified.关键词：Compact antenna test range;Shaped antenna;Reflectors antenna synthesis;Cross polarization;Antenna configuration3|165|5更新时间：2025-12-08
- 摘要：A novel algorithm of real phase-only nulling synthesis for phased array antennas is proposed,which is based on the "Element Null Vector’’and Gram-Schmidt orthogonalization. It is effective to set wide null and low notch. In addition,the rise of notch level due to the phase quantization is investigated too.关键词：phased array antenna;Phase weight;Pattern nulling;adaptive array;Phase quantization2|159|5更新时间：2025-12-08
- 摘要：An element with mixture structure of waveguides and planar dielectric layers is analyzed using spectral domain approach and eigenfunction technique. The small element has a higher gain than that of a horn. The computational results of pattern,gain and VSWR are agreeable to the experimental ones.关键词：planar antenna;Mixture structure;Spectral domain approach;Eigenfunction2|47|1更新时间：2025-12-08
- 摘要：Great attention has been paid to calculating conveniently the electromagnetic field due to a loop antenna buried in stratified media. It is quite difficult because this topic is involved with the computation of Sommerfeld-Type integral. In this paper the closed-form expressions of far field of a loop antenna in a three-layered conducting medium are obtained rapidly by using a new technique to evaluate Sommerfeld-Type integral with the aid of the complex image theory. The present approach can be also used to get the far field formulas of other similar cases.关键词：Layered conducting medium;Loop antenna;Far field;Sommerfeld integral;Complex image theory2|100|1更新时间：2025-12-08
- 摘要：Conventional meteorologic radar cannot distinguish radar reflectivity and specific attenuation of rain. There is some principled error to measuring rain by it. A new method on inversing rain rate distribution along Earth-Space path by radar-satellite system is presented in this paper. A recurrent formula of specific attenuation of rain is derived. A radar-satellite system for measuring rain is given. The typical results of distribution of rainfall rate along Earth-Space path are measured by this system.关键词：Radar reflectivity;Specific attenuation of rain;Rainfall rate3|95|0更新时间：2025-12-08
- 摘要：The necessity and possibility of the integration of DNS and the approach to the integration are expounded. The error model and the Kalman filtering model are given. There are three kinds of integration modes according to different measurements. By simulated calculation, the corresponding curves are given. When adopting the pseudorange and its rate as observed variables,the integration mode is the best. The position accuracy can attain the order of meter on each axis,and the heading accuracy can be raised to 0. 2°.关键词：DNS/GPS integrated navigation system;Indirected Kalman filtering;Modes of filtering2|112|1更新时间：2025-12-08
- 摘要：The scattering solution for generalized Maliuzhinets method of a half-plane wedge with impedance faces in first studied,then the concept of equivalent edge currents appliect conducting wedge is extended to wedges with impedance faces. Based on the constructed equivalent edge currents,the RCS of flyer’s wings covered with radar absorbing material is computed and examined. This method is specially effective to compute RCS of large electric size wings.关键词：Wedge;equivalent edge currents;RCS;Plate;Coating3|192|11更新时间：2025-12-08
- 摘要：The electromagnetic scattering by buried objects in dispersive media is calculated by FD-TD method. The FD-TD formula and the absorbing boundary condition in Debye dispersive media are deduced,respectively. The validity of this method in lossy media is verified through comparing the FD-TD’s result with other one. The propagation of transient pulses in dispersive media is studied in detail. The scattering pulses and the wiggle traces are given for several typical buried objects.关键词：FD-TD method;dispersive media;Buried objects;Baseband pulse;electromagnetic scattering2|108|7更新时间：2025-12-08
- 摘要：Modified steepest descent method for inverting the impulse response of target and correlation coefficient criterion for estimating the deconvolution error and controlling iteration number of times are presented. The inversion results from the measured transient electromagnetic pulse response of a conducting sphere show that correlation coefficient criterion is a simple and reliable criterion and that modified steepest descent method is an efficient method for inverting the impulse response of target in time-domain and is superior to modified conjugate gradient method.关键词：Impulse response;Deconvolution;Modified steepest descent method;Correlation coefficient criterion2|107|3更新时间：2025-12-08
- 摘要：This paper employs a new method to study Bragg resonator,in which the reflective section is regarded as an axisymmetric varying section waveguide. We study the characteristic of reflector under the assumption of multiple mode. Our calculated results are in agreement with experimenttal measurments. At last ,the total quality factor of resonator is given.关键词：Bragg resonator;Varying section waveguide;mode coupling2|182|13更新时间：2025-12-08
- 摘要：A new method is proposed for estimating the parameters of two-dimensional damped/undamped harmonics. This method constructs three ESPRIT matrix pencils from the original data,combines engendecomposition filtering and the total least squares method go reduce the generalized eigenvalue problems of the noisy ESPRIT matrix pencils to the eigenvalue problems of three square matrices,and yields two sets of estimates of pole components and a set of estimates of the products of pole components. Utilizing a simple pairing algorithm, two-dimensional poles are obtained according to these three sets of estimates. The method requires quite small computations and it can be implemented by using a parallel algorithm. Simulations are provided to show the accuracy of this method.关键词：multi-dimensional signal processing;Two-dimensional harmonics;parameter estimation;ESPRIT matrix pencil2|59|0更新时间：2025-12-08
- 摘要：The formulas and algorithms are presented for the computation of the modified Bessel functions of imaginary orders and their derivatives. The numerical results show that the accuracy of the algorithms is more than 10 significant digits.关键词：Bessel functions;The modified Bessel functions of imaginary orders;Backward recurrence algorithm;Asymptotic expansion2|120|1更新时间：2025-12-08
- 摘要：With the method of plane wave spectrum（PWS） , a 2-D electromagnetic scattering problem,the influence of a cylinder on a continuous antenna,is solved. The formulae given in this paper are accurate.关键词：D Scattering problem;low sidelobe;Cylindric scattering object;Plane wave spectrum （PWS）2|48|1更新时间：2025-12-08
- 摘要：The generalized spectral domain-exponential matrix technique is used to study the reflection and transmission properties of multilayered uniaxial chiral composites which possess bi-chirality structures. Numerical results are presented to demonstrate the influences of the orientation axis,lossness, chirality and non-reciprocity parameters on the reflection and transmission coefficients. Especially ,the effect of cross-polarized transformation is considered. Our results suggest that bianisotropic uniaxial chiral materials have potential applications for the design of novel polarization transformers.关键词：Bianisotropy;Uniaxial chiral medium;Generalized spectral domain-exponential matrix technique;Cross-polarized transformation2|47|0更新时间：2025-12-08
- 摘要：According to the properties of conduction of thermal wave,one-dimension heat conduction equation is solved with matrix method. Heat conduction model of multi-layer pyroelectric detector is given.Dynamic pyroelectric response of the detector to sinusoidally modulated radiation is represented by matrices. With the results of matrix analysis,the influence of a thermal insulating layer on the improvement of the responsivity of the detector is discussed. Requirements to the thermal insulating layer are proposed. Influences of the parameters of each layer in the multi-layer detector on the performance of the detector are also discussed.关键词：Pyroelectric detector;Heat conduction;Current responsivity;Matrix method2|102|3更新时间：2025-12-08
- 摘要：The technique of non-equiripple approximation for filter characteristics is presented.In this technique the characteristic function is composed of the rational function constructed by Chebyshev polynomial and coefficients related to frequency. Thus the attenuation characteristics close to thos of elliptic filter for the same order are obtained. The computing results show that the technique of non-equiripple approximation has advantages over Chebyshev filter and inverse Chebyshevfilter. The design procedure is not only clear in theory,but also simple and easy to complete computer program. The approximation method based on non-equiripple is an intermediary between equiripple approximation and maximally flat approximation. It is quite useful for filter design.关键词：symmetry loads;Filter characteristic;Non-equiripple approximation2|92|1更新时间：2025-12-08
- 摘要：Based on Fresnel-Kirchhoff principle,a general representation of field of diffraction by multiple knife-edge is given under the condition of existence of ground reflectio. Meanwhile,a way of sloving the diffraction field by a flat-topped obstacle with bevel edge is obtained. The method is to find the sum of the field of eight rays. The formulas we got are convenient for practical caculation and have clear physical conception.关键词：Diffraction;reflection;Flat-topped obstacle with bevel edge.2|116|5更新时间：2025-12-08
- 摘要：A new AR mixed model statistics method dealing with electric measure data of aircraft is presented. The method overcomes the difficulty that the AR noise in observation data is unknown. The algorithm is linear and has fast computer speed and so can be applied to the timed data processing. The simulated results show that the new method has higher accracy than the usual difference method.关键词：Polynomial sign;data processing;Mixed AR model;parameters estimation2|171|20更新时间：2025-12-08
- 摘要：A microwave resonator probe method for diagnosing local plasma electron density is described,and the measurement principle,design method and experiment results are included. The experimental results show that the microwave resonator probe is much more reliable than Langmuir probe in the measurement of plasma density due to its completeness. The spatial resolution depends upon the size of microwave resonator probe.关键词：Plasma diagnostic;Probe;Plasma density2|344|22更新时间：2025-12-08
- 摘要：In this paper we discuss a new method which can reduce enormously the computation of the disturbed electromagnetic field due to the change of the paramter of a local medium or boundary condition. Being different from the Disturbance Theory,this method gets much less limitations on the size or parameter of the local medium.关键词：electromagnetic field;Tolerance method;electromagnetic scattering2|30|2更新时间：2025-12-08
- 摘要：The rapid progress and important achievements of the Transmission-line Matrix（TLM） method and its applications are reviewed. It shows that,as the rapid development of the computer technology,the TLM method will be further developed and more and more applications in various fields can be found.关键词：TLM method;Numerical calculations for electromagnetics;electromagnetic scattering;Waveguide structure;Network parameters2|507|32更新时间：2025-12-08
- 摘要：Describes some recent advances in the area of high-power microwave generation by Intense Relativistic Electronic Beams,and presentes the classification,the status of techniques and theory for high-power microwave tube.关键词：High-current relativistic electronic;high-power microwave;Recent developments2|50|8更新时间：2025-12-08
- 摘要：The paper analyses systematically the electromagnetic characteristics of cylindrical reentrant cavity, including computation method of resonance frequency, seperation of various resonance modes and calculation of Q0. A program is compiled to simulate the mechanical tuning of the cavity for engineering. And the cavity is employed successfully in W-band harmonic oscillator.关键词：Resonators;Cylindrical reentrant cavities;Resonance frequencies;Quality factors;Harmonic oscillators2|68|2更新时间：2025-12-08
- 摘要：The scattered far field from a perfectly conducting circular cylinder with a fin is calculated using a hybrid method which combines Physical Optical（PO） ,FOCK theory ,Physical Theory of Diffraction（PTD） , Geomtrical Theory of Diffraction（GTD） with Moment of method（MM） . Results are compared to those of MM and those of Micheali’s theoretical calculation and measured data,and quite good agreement is obtained. In comparison to Micheali’s theoretical analysis,the hybrid method is valid for any magnitudes of cylinder radius and the fin width,and for any incident angle.关键词：Cylinder with a fin;scattering;hybrid method2|49|1更新时间：2025-12-08
- 摘要：A rigorous analysis of the twin wave modes in imperfect coaxial line is presented,with emphasis on the transmission line mode EH mode and the commonly used EHop modes and HEop modes（pa≥1） ,and the variational expression of the cut-off frequency is derived. Then the formulation of the complex propagation constant is given. It is shown that the attenuation constant is the appoximation of the real part of the formulation in this paper.关键词：Imperfect coaxial line;Twin wave modes;Complex propagation constant;Variational method4|42|0更新时间：2025-12-08
- 摘要：A more stable and accurate recursing formula and computing procedure to calculate the scattering coefficients anⅡ,bnⅠ and the internal coefficients cn（j）,dn（j）,gn（j）,fn（j） are proposed. The numerical calculations and tests based upon the recursive algorithms are presented. This procedure can be used to inhomogeneous cylinders with any complex refractive indices and size parameters.关键词：electromagnetic scattering;Multilayered cylinder;Recursive algorithms2|284|22更新时间：2025-12-08
- 摘要：A method for determining constitutive parameters from scattering parameters of chiral slab is presented. It will be shown that complex permittivity,permeability parameters and chiral parameters of the chiral slab can be solved from the measured reflective and transmission fields. The rotation angle and axial ratio of the transmission field will also be determined in this way. The procedure is very simple and easy to obtain accurate results.关键词：Chiral materials;Scattering parameters;Constitutive paramters4|59|8更新时间：2025-12-08
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备09064830号-19
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0