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em scattering from Rough Surface

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Journal of Systems Engineering and Electronics 1997年第4期8卷 34-39页

作者： Lu Guizhen & Mao Zhiji P. O. Box 29, Beijing Broadcasting Institute, 100024, P. R. China P. O. Box 29 Beijing Broadcasting Institute 100024 P. R. China

In this paper, Laplace transform method is used to solve the problem of wave scattering from the rough surface. The rough surface is described by y=ζ (x, z) . First, we make Laplace transform to y variable, then do the Fourier transform to x and z variables. In the k space, we can obtain the solution of the problem of wave scattering by simple algebraic operation. Finally, the Laplace inverse transform is performed by complex variable method and Fourier inverse transform by stationary phase method.

关键词： em scattering Laplace transform Fourier transform.

HIGH-ORDER NYSTRM METHOD FOR THE EFIE OF em scattering PROBLemS

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Journal of Electronics(China) 2004年第6期21卷 476-481页

作者： ZhangXiaojuan InstituteofElectronics ChineseAcademyofSciencesBeijng100080

Nystrm method is a new method for solving electromagnetic scattering problems. This paper gives the detailed description on high-order Nystrm method used for the electric field integral equation of electromagnetic sca... 详细信息

关键词： em scattering High-order Nystrm method

Backscattering from small-scale breaking wave turbulence structure generated by FLUENT

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Chinese Physics B 2014年第12期23卷 159-165页

作者：罗根张民 School of Physics and Optoelectronic Engineering Xidian University

A breaking wave can exert a great influence on the electromagnetic（em） scattering result from sea surfaces. In this paper, the process of small-scale wave breaking is simulated by the commercial computational fluid dynamics（CFD）software FLUENT, and the backscattering radar cross section（RCS） of the turbulence structure after breaking is calculated with the method of moments. The scattering results can reflect the turbulent intensities of the wave profiles and can indicate high polarization ratios at moderate incident angles, which should be attributed to the incoherent backscatter from surface disturbance of turbulence structure. Compared with the wave profile before breaking, the turbulence structure has no obvious geometrical characteristic of a plunging breaker, and no sea spikes are present at large incident angles *** summary, the study of em scattering from turbulence structure can provide a basis to explain the anomalies of em scattering from sea surfaces and help us understand the scattering mechanism about the breaking wave more completely.

关键词： FLUENT turbulence structure em scattering high polarization ratios

New hybridization of PO, SBR, and MoM for scattering by large complex conducting objects

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Journal of Systems Engineering and Electronics 2007年第4期18卷 726-730页

作者： Dong Chunzhu Geng Fangzhi Yin Hongcheng Wang Chao National Electromagnetic scattering Lab. Beijing 100854 P. R. China Dept. of Electronic Warfare AFRA Wuhan 430019 P. R. China

As a marked extension of the traditional MoM-PO （method of moment-physical optics） hybrid method, a new hybridization of PO, SBR, and MoM （MoM-SBR/PO） is presented to calculate the multireflection contribution in the PO region efficiently by introducing the method of SBR based on RDN notion, which avoids the time-consuming iterative procedure and the choice of proper Green＇s function. As compared with the traditional MoM-PO hybrid method, the calculation efficiency of the proposed method is greatly improved, and its validity is verified by numerical results.

关键词： the method of moment (MoM) physical optics (PO) hybrid method shooting and bouncing ray(SBR) em scattering radar cross section (RCS)

SCTE: RCS Prediction System for ComplexTarget and Interaction with Environment

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Wuhan University Journal of Natural Sciences 1999年第3期4卷 299-303页

作者： Cao Qin-feng Lu Shu Xu Peng-gen College of Electronic Information Wuhan University Wuhan China

A RCS prediction system named SCTE (scattering from Complex Target and Environment) for calculating high-frequency electromagnetic scattering from complex target within complex environment is presented. The scattering body is described by Computer-Aided-Design (CAD) representations in which the complex body is modeled as NURBS (Non-Uniform Rational B-spline) surfaces. The complex environment (rough surface of sea or ground) is also carefully considered by using fractal function. scattering fields are calculated by using physical optics and the equivalent currents methods. There is a good agreement between the present results and that from measurements which demonstrates the accuracy of this system.

关键词： RCS complex target em scattering

Application of Improved Z-Buffer Technique to RCS Computation

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 53-55页

作者： Cao Qinfeng, Xu Penggen(College of Electronic Information, Wuhan University, Wuhan 430072, China) College of Electronic Information Wuhan University Wuhan China

This paper presents a new method for computation of the monostatic radar cross section (RCS) of electrically large conducting objects. Compared with the traditional Z-buffer technique, the improved one can record not only the illuminated surface of the body, but also the information about the shadowed part. So multi-scattering and RCS of cavity can be calculated. The second advantage of it is using dual representation, of the target's facet surface, in which the illuminated part is treated as bicubic patches for RCS calculation, and is simplified to flat facet when ray tracing is done. Excellent agreement with the experiment has been obtained.

关键词： Key words RCS complex target Z buffer em scattering

The Electromagnetic scattering by Buried Complex Objects

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Journal of Systems Engineering and Electronics 1997年第4期8卷 17-22页

作者： Lu Shu, Chang Mei & Xu Penggen Dept. of Radio Physics, Wuhan University, 430072, P. R. China Dept. of Radio Physics Wuhan University 430072 P. R. China

The solution of scattering problem of buried complex bodies needs to not only consider the scattering from the complex bodies, but also apply the boundary conditions in two different types of coordinate systems. This paper applies the conversion technique of vector wave functions combined with the three-dimensional unimoment method to effectively solve this type of complex electromagnetic problem. Using the conversion relations between the cylindrical and spherical vector wave functions, two types of boundary-value problems are conveniently jointed. Both the vector wave function expansion and the multipole expansion belong to eigen function expansion methods and have the same convergence rate. But the former is more rigorous in theory and needs to calculate only two types of eigen components while the latter needs to calculate four types.

关键词： em scattering Buried complex object Unimoment method.

Genetic Algorithm and Its Application to Absorbing Coating Optimization

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Advances in Manufacturing 1998年第1期 57-61页

作者： Ni Weili Zeng Lin (School of Communication and Information Engineering)

As a “global” numerical optimization method, genetic algorithm is briefly introduced. It is applied to optimize the absorbing coating to reduce em scattering, leading to satisfactory results.

关键词： genetic algorithm optimization em scattering

Solution of scattering from Homogeneous Dielectric Object Using Fast Multipole Method

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Solution of Scattering from Homogeneous Dielectric Object Us...