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Unification and Comparison between Two Concepts of Radar Target Angular Glint

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Journal of Systems Engineering and Electronics 1992年第1期3卷 35-44页

作者： Hongcheng, Yin peikang, huang Beijing Institute of Environmental Features Beijing China

This paper provides a general proof of unification between two concepts of radar target an gular glint. The analysis of a two-point target model, consisting of a electrically and a magnetically ideal dipole, shows the relation, difference and equivalent condition between them more clearly. Angular glint has been synthesized from the measured data of radar echo phase, and compared with the theoretical result.

关键词： Image processing Radar measurement

Equivalent Currents on an Anisotropic Material Backed by a Metal Surface and Their Relation

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Journal of Systems Engineering and Electronics 2000年第4期11卷 1-10页

作者： huang peikang Yin Hongcheng National Electromagnetic Scattering Laboratory Beijing 100854P.R.China

Based on a first-order state-vector differential equation representation of Maxwell's equations, an analytical formulation is derived for the equivalent currents on an anisotropic material backed by a metal surface, and the relation between two currents is also considered. These expressions are degenerated into the common forms for some simple cases. This effort will provide the theoretical preparation for the approximate calculation of electromagnetic scattering from a conducting object coated by an anisotropic material.

关键词： Radar absorbing material Anisotropic Equivalent currents Electromagnetic scattering

Velocity compensation methods for LPRF modulated frequency stepped-frequency(MFSF) radar

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Journal of Systems Engineering and Electronics 2010年第5期21卷 746-751页

作者： Guifen Xia Hongyan Su peikang huang Beijing Institute of Remote Sensing Equipment Beijing 100039 E R. China

In the high speed target environment,there exists serious Doppler effect in the low pulse repetition frequency（LPRF） modulated frequency stepped frequency（MFSF） radar *** velocity range of the target is large and the velocity is high ambiguous,so the single method is difficult to satisfy the velocity measurement *** this problem,a novel method is presented,it is a combination of cross-correlation inner frame velocity measurement and range-Doppler coupling velocity *** cross-correlation inner frame method,overcoming the low Doppler tolerance of the cross-correlation between frames,can obtain the coarse velocity of the high speed target,and then the precision velocity can be obtained with the range-Doppler coupling *** simulation results confirm the method is effective,and also it is well real-time and easy to the project application.

关键词： modulated frequency stepped-frequency(MFSF) radar low pulse repetition frequency(LPRF) cross-correlation inner frame range-Doppler coupling.

Comparison between two concepts of angular glint:general considerations

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Journal of Systems Engineering and Electronics 2008年第4期19卷 635-642页

作者： Wang Chao Yin Hongcheng huang peikang Information Engineering School Communication Univ. of China Beijing 100024 P. R. China National Electromagnetic Scattering Lab. Beijing 100854 P. R. China

Angular glint can be interpreted as a distortion of the radar echo signal phase front, or alternatively, a tilt of the direction of energy flow from the radial direction. As the complementarities and support of argumentation in our previous work, a general discussion about two concepts of angular glint is made based on electromagnetic theory to demonstrate that these two concepts are equivalent when geometrical optics approximation is used and＇ the receiving antenna is linearly polarized.

关键词： angular glint radar target electromagnetic scattering polarization

Research on keystone formatting based on non-baseband interpolation

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Journal of Systems Engineering and Electronics 2010年第4期21卷 562-565页

作者： Yufei Cao Xiaoguang Qu peikang huang Beijing Institute of Radio Measurement Beijing 100039 R R. China Defense Technology Academy of China Aerospace Science & Industry Corporation Beijing 100039 R R. China

When there is Doppler ambiguity number mutation,keystone formatting is no longer valid because of integration performance deterioration and false velocity estimation.A novel keystone formatting method based on non-baseband interpolation is *** has a different half blind velocity range comparing with normal keystone ***,there is non-superposition between half-blind-velocity-range of keystone formatting based on baseband and that of non-baseband *** a synthesizing keystone formatting is proposed to avoid the half-blind-velocity *** results of the proposed method show that integration deterioration and velocity estimation falsity can be eliminated effectively.

关键词： keystone formatting half-blind-velocity coherent integration velocity estimation.

Boost-Phase ballistic missile trajectory estimation with ground based radar

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Journal of Systems Engineering and Electronics 2006年第4期17卷 705-708页

作者： Tang Yuyan huang peikang The Second Academy of China Aerospace Science & Industry Corporation Beijing 100854 P.R.China

A conditional boost-phase trajectory estimation method based on ballistic missile （BM） information database and classification is developed to estimate and predict boos-phase BM trajectory. The main uncertain factors to describe BM dynamics equation are reduced to the control law of trajectory pitch angle in boost-phase. After the BM mass at the beginning of estimation, the BM attack angle and the modification of engine thrust denoting BM acceleration are modeled reasonably, the boost-phase BM trajectory estimation with ground based radar is well realized. The validity of this estimation method is testified by computer simulation with a typical example.

关键词： trajectory estimation boost-phase ground based radar ballistic missile.

Image edge detection based on beamlet transform

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Journal of Systems Engineering and Electronics 2009年第1期20卷 1-5页

作者： Li Jing huang peikang Wang Xiaohu Pan Xudong China Aerospace Science 8z Industry Corporation Beijing 100854 P. R. China

Combining beamlet transform with steerable filters, a new edge detection method based on line gradient is proposed. Compared with operators based on point local properties, the edge-detection results with this method achieve higher SNR and position accuracy, and are quite helpful for image registration, object identification, etc. Some edge-detection experiments on optical and SAR images that demonstrate the significant improvement over classical edge operators axe also presented. Moreover, the template matching result based on edge information of optical reference image and SAR image also proves the validity of this method.

关键词： edge detection beamlet transform steerable filters optical image SAR image.

Solution for polarimetric radar cross section measurement and calibration

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Journal of Systems Engineering and Electronics 2014年第2期25卷 211-216页

作者： peikang huang Chao Ning Xiaojian Xu Hua Yan Zhaoguo Hou Science and Technology on Electromagnetic Scattering Laboratory School of Electronic and Information Engineering Beihang University

The exact radar cross-section （RCS） measurement is difficult when the scattering of targets is low. Ful polarimetric cali-bration is one technique that offers the potential for improving the accuracy of RCS measurements. There are numerous polarimetric calibration algorithms. Some complex expressions in these algo-rithms cannot be easily used in an engineering practice. A radar polarimetric coefficients matrix （RPCM） with a simpler expression is presented for the monostatic radar polarization scattering matrix （PSM） measurement. Using a rhombic dihedral corner reflector and a metal ic sphere, the RPCM can be obtained by solving a set of equations, which can be used to find the true PSM for any target. An example for the PSM of a metal ic dish shows that the proposed method obviously improves the accuracy of cross-polarized RCS measurements.

关键词： radar cross section (RCS) polarization scattering ma-trix (PSM) polarimetric calibration polarimetry.

Effect of Direct Aging on Corrosion Behavior of AlSi10Mg Alloy Fabricated by Laser Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 266-282页

作者： Zhen Zhang Zhanyong Zhao Xiaofeng Li Beibei Wang peikang Bai Shanxi Key Laboratory of Controlled Metal Solidification and Precision Manufacturing School of Materials Science and EngineeringNorth University of ChinaTaiyuan030051China Technical Center Taiyuan Iron and Steel(Group)Co.LtdTaiyuan030003China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Effect of direct aging of 170℃on corrosion behavior of laser powder bed fused AlSi10Mg(LPBF-AlSi10Mg)was studied by microstructure analysis,electrochemical analysis and X-ray photoelectron *** results show that direct aging of 170℃has little effect on melt pool and Si cellular structure,but promotes the precipitation of nano-Si particles and releases the residual *** increasing aging time from 0 to 4 h to 24 h,the corrosion property of the LPBF-AlSi10Mg is deteriorated,which is evidenced by increased corrosion current density and decreased pitting potential and polarization *** increasing the aging time,the thickness of the oxide film formed on surface of the LPBF-AlSi10Mg *** Si content of the oxide film of the sample aging for 4 h is the lowest,9.42 at.%,and it is the highest,18.62 at.%,for the sample aging for 24 *** electrochemical noise analysis reveals that the middle-frequency contribution of the Hilbert spectrum is responsible for the deteriorated corrosion performance,which corresponds to metastable pitting initiated by nano-Si particles.

关键词： Laser powder bed fusion AlSi10Mg Direct aging Corrosion