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A self-calibration algorithm for cross array in the presence of mutual coupling

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Science china(Information Sciences) 2011年第4期54卷 836-848页

作者： HU XiaoQin 1,2,CHEN Hui 2,WANG YongLiang 2 & CHEN JianWen 2 1 College of Electronic Science and Engineering,National University of Defense Technology,Changsha 410073,china 2.key lab of wuhan radar academy,wuhan 430019,china College of Electronic Science and Engineering National University of Defense Technology Changsha China key lab of wuhan radar academy Wuhan China

In this paper,a novel blind mutual coupling self-calibration algorithm especially tailored to cross array is *** method compensates for the mutual coupling not only between sensors in each subarray but also between two *** the property of coupling matrix,the proposed method requires neither the calibration sources in known locations nor the multidimensional nonlinear *** method can jointly estimate the DOAs of the incoming signals and the unknown mutual coupling coefficients,and has high estimation precision and low computational *** analysis and computer simulations show the effectiveness of the proposed algorithm.

关键词： cross array mutual coupling self-calibration DOA estimation

Numerical study of the auroral particle transport in the polar upper atmosphere

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Science china(Technological Sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2, MA ShuYing1,2 & PU ZuYin3 1 School of Electronic Information, wuhan University, wuhan 430079, china 2.key laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, wuhan 430079, china 3 School of Earth and Space Sciences, Peking University, Beijing 100871, china School of Electronic Information Wuhan University Wuhan China key laboratory of Geospace Environment and Geodesy Ministry of Education of PRC Wuhan China School of Earth and Space Sciences Peking University Beijing China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2), to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2 ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

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Robust Adaptive Beamforming Based on Penalty Function Under Steering Vector Errors

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Robust Adaptive Beamforming Based on Penalty Function Under ...

2002年第6届信号处理国际会议

作者： Li Rongfeng Wang Yongliang Wan Shanhu key research lab wuhan radar academy wuhan 430010 china

＜正＞ The presence of random steering vector errors degrades severely the performance of adaptive beamforming, and results in adapted beam patterns with high sidelobes and distorted mainbeams. In this paper, the penalty function is exploited to prevent signal cancellation and remedy beam distortion due to steering vector errors. Computer simulation results are presented for illustration.

关键词： Adaptive array Penalty function Adapted beam pattern

Modeling and Suppression of Clutter for Airborne Fire Control radar with Conformal Antennas Array

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Modeling and Suppression of Clutter for Airborne Fire Contro...

2011 CIE International Conference on radar(radar 2011)

作者： K.Q.Duan W.C.Xie Y.L.Wang key research lab. wuhan radar academy wuhan 430019 china

Conformal antennas array （CAA） offer many advantages over conventional planar antennas array （PAA） such as less payload weight, larger effective aperture and increased field of view without mechanically canting or rotating the array. In this paper, airborne fire control radar （AFCR） with CAA is analyzed in terms of antennas modeling, working mechanism, subarray synthesis, clutter characteristics and clutter suppression method, etc. Firstly, the mathematics model and geometry configuration of AFCR with CAA are given, and the manners of subarray division and working are obtained based on the requirement for moved target detection of AFCR, and the pattern properties of CAA are analyzed. Secondly, the clutter spectrum distribution in space-time plane is analyzed. Finally, clutter suppression performance of existing space- time adaptive processing （STAP） techniques for practice is compared, and the minimum detectable velocity of AFCR with CAA is shown.

关键词： Airborne fire control radar Conformal antennas array Space-time adaptive processing Clutter suppression

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空间谱估计算法结构及仿真分析

系统工程与电子技术 2001年第8期23卷 76-79页

作者：陈辉王永良武汉雷达学院兵器运用工程重点实验室 430010

在对高分辨空间谱估计算法研究的基础上 ,提出了空间谱估计算法的基本结构 ,这种结构包含两个组成部分 :预处理算法和波达方向估计 (DirectionofArrival,DOA)算法。同时对多种预处理算法和DOA估计算法进行了分类说明。最后通过大量的计... 详细信息

在对高分辨空间谱估计算法研究的基础上 ,提出了空间谱估计算法的基本结构 ,这种结构包含两个组成部分 :预处理算法和波达方向估计 (DirectionofArrival,DOA)算法。同时对多种预处理算法和DOA估计算法进行了分类说明。最后通过大量的计算机仿真实验比较了各种算法的性能。

关键词：空间普估计信号处理算法信号估计

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Evaluating the quality of statistical data based on the Bootstrap method

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Evaluating the quality of statistical data based on the Boot...

2011 International Conference on Business Management and Electronic Information(BMEI 2011)

作者： Yang Yan-fei Air Force radar academy wuhan 430019 china

It is an important method to evaluate the quality of statistical data based on statistical *** in practice,the key work of this method is to find out the statistic’s *** the advantage of bootstrap in exploring the statistic’s distribution,we introduce the bootstrap to the evaluation of the quality of statistical data,and give a general frame of test for quality of statistical *** last,simulation and verification are made based on the survey data from government.

关键词： data quality bootstrap logarithm normal distribution tests for normality

Analysis of STAP on MDV for Spaceborne SAR-GMTI Applications

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Analysis of STAP on MDV for Spaceborne SAR-GMTI Applications

2006 CIE International Conference on radar

作者： Chen Jianwen 1 Ren lei 1 2 1.key research lab wuhan radar Institute wuhan Hubei 430019 china 2.National University of Defense Technology Changsha Hunan 410073 china

Space-time adaptive processing （STAP） holds tremendous potential for the new generation spaceborne radar to get good performance of ground/sea moving target indicator （GMTI）.A system scheme based on the fully adaptive space-time processing of spaceborne SAR-GMTI mode of operation is presented in this *** the minimum detectable velocity （MDV） of target in GMTI mode is *** analysis and simulations demonstrate the effectiveness of the system scheme.

关键词： Space-time adaptive processing (STAP) ground moving target indicator (GMTI) spaceborne SAR-GMTI minimum detectable velocity (MDV).

An eigenstructure-based 2D DOA estimation method using dual-size spatial invariance array

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Science china(Information Sciences) 2011年第1期54卷 163-171页

作者： YANG XueYa,CHEN BaiXiao & CHEN YunHai National key lab of radar Signal Processing,Xidian University,Xi’an 710071,china National key lab of radar Signal Processing Xidian University Xi’an China

A sparse planar array vertically placed in y-z plane is proposed to improve the angle estimation accuracy of sources in low angle region with reflection *** two sizes of spatial invariances along both dimensions,the array estimates the azimuth and elevation angles using unitary ESPRIT(estimation of signal parameters via rotational invariance techniques).The first spatial invariance with a displacement of half-wavelength yields unambiguous coarse estimates of high-variance,while the second spatial invariance with much larger a displacement of subarrays obtains cyclically ambiguous fine estimates of *** final estimates are obtained by disambiguating fine estimates with coarse estimates.A novel pairing scheme is proposed to pair both the azimuth and elevation,coarse and fine angle estimates of the same *** addition, a new method is presented to calculate 2D angles,which substitutes the estimated elevation angle into the sin relative to the y-axis to get the azimuth *** real-valued processing and array aperture extension, the new DOA measuring method de-correlates the multipath signals and enhances angle resolution with no extra antennas and computational *** results show the effectiveness of the proposed technique and its advantages over the conventional methods.

关键词： DOA estimation sparse array correlated signals unitary ESPRIT dual-size spatial invariances

Progress in technology for the 2005 height determination of Qomolangma Feng (Mt. Everest)

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Science china Earth Sciences 2006年第5期49卷 531-538页

作者： CHEN Junyong1,2, YUAN Janli1,2, GUO Chunxi1,2, ZHANG Yanping1 & ZHANG Peng1,2 1. State Bureau of Surveying and Mapping, Beijing 100830, china 2. School of Geodesy and Geomatics, wuhan University, wuhan 430079, china State Bureau of Surveying and Mapping Beijing China School of Geodesy and Geomatics Wuhan University Wuhan China

In 2005 china carried out a new geodetic campaign for the height determination of Qo- molangma Feng——Mt. Everest (QF in short). The technical progresses in geodesy for the 2005 campaign are presented in the paper. GPS positioning was the key technique in the campaign. After summarizing the experiences and lessons of the GPS positioning on the QF summit in the previous QF height determination campaigns, some measures were taken to raise the accuracy and reliability of the height determination with GPS techniques. In order to raise the accuracy of the height deter- mination of the QF summit with classical geodetic techniques, laser ranging was used together with the trigonometric levelling in the 2005 campaign. It is the first time in china the thickness of the ice-snow layer on the QF summit was measured by ground penetrating radar integrated with GPS. The local gravity field and geoid in the QF area was improved on the basis of earth gravity field model integrated with new ground gravity data, DTM data and GPS leveling data in the QF area. In the 2005 campaign the normal height and orthometric height (height above sea level) of the snow surface of the QF summit were obtained as 8846.67 m and 8847.93 m respectively. The orthometric height of the rock surface of the QF summit is 8844.43 m,and the thickness of the ice-snow layer on the QF summit is 3.50 m.

关键词： Qomolangma Feng, Mt. Everest, height determination, GPS, gravity field, ground penetrating radar.

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