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Joint 2D-DOA and polarization estimation for sparse nonuniform rectangular array composed of spatially spread electromagnetic vector sensor

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Journal of Systems Engineering and Electronics 2020年第6期31卷 1116-1127页

作者： MA Huihui tao haihong National Laboratory of Radar Signal Processing Xidian UniversityXi'an 710071China

In this paper,a sparse nonuniform rectangular array based on spatially spread electromagnetic vector sensor(SNRASSEMVS)is introduced,and a method for estimating 2D-direction of arrival(DOA)and polarization is devised.Firstly,according to the special structure of the sparse nonuniform rectangular array(SNRA),a set of accurate but ambiguous direction-cosine estimates can be obtained.Then the steering vector of spatially spread electromagnetic vector sensor(SSEMVS)can be extracted from the array manifold to obtain the coarse but unambiguous direction-cosine estimates.Finally,the disambiguation approach can be used to get the final accurate estimates of 2DDOA and polarization.Compared with some existing methods,the SNRA configuration extends the spatial aperture and refines the parameters estimation accuracy without adding any redundant antennas,as well as reduces the mutual coupling effect.Moreover,the proposed algorithm resolves multiple sources without the priori knowledge of signal information,suffers no ambiguity in the estimation of the Poynting vector,and pairs the x-axis direction cosine with the y-axis direction cosine automatically.Simulation results are given to verify the effectiveness and superiority of the proposed algorithm.

关键词： sparse nonuniform rectangular array(SNRA) spatially spread electromagnetic vector sensor(SSEMVS) directioncosine polarization mutual coupling

Design of synthetic aperture radar low-intercept radio frequency stealth

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Journal of Systems Engineering and Electronics 2020年第1期31卷 64-72页

作者： CHANG Wensheng tao haihong LIU Yanbin SUN Guangcai National Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China School of Physics and Optoelectronic Engineering Xidian UniversityXi’an 710071China

Not confined to a certain point,such as waveform,this paper systematically studies the low-intercept radio frequency(RF)stealth design of synthetic aperture radar(SAR)from the system level.The study is carried out from two levels.In the first level,the maximum low-intercept range equation of the conventional SAR system is deduced firstly,and then the maximum low-intercept range equation of the multiple-input multiple-output SAR system is deduced.In the second level,the waveform design and imaging method of the low-intercept RF SAR system are given and verified by simulation.Finally,the main technical characteristics of the lowintercept RF stealth SAR system are given to guide the design of low-intercept RF stealth SAR system.

关键词： synthetic aperture radar(SAR)imaging low-intercept radio frequency(RF)stealth low-intercept range low-intercept waveform

Estimation of DOA and Polarization with COLD Sensors Based on Quaternion Model

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Wuhan University Journal of Natural Sciences 2017年第4期22卷 361-368页

作者： ZHAO Jichao tao haihong China National Laboratory of Radar Signal Processing Xidian University Xi'an 710071 Shaanxi China

The quaternion multiple signal classification（Q-MUSIC）algorithm generally requires four-dimensional spectral peak search to estimate the direction of arrival（DOA）and polarization parameters,which would result in the huge computation burden.A dimension reduction Q-MUSIC algorithm（DRQ-MUSIC）based on L-shaped array is presented to reduce the computational complexity in this paper.The proposed algorithm divides the steering vector into three parts,and estimates each part separately,thus DOA and polarization parameters can be estimated only by N times one-dimensional spectral peak search,where N denotes the sources number.Besides,pair match is not required.Finally,simulation examples demonstrate the effectiveness and feasibility of the proposed algorithm.

关键词： dimension reduction quaternion MUSIC（DRQ-MUSIC） direction of arrival（DOA） polarization

A multi-frame track-before-detect algorithm based on root label clustering for multiple targets

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Chinese Journal of Aeronautics 2022年第5期35卷 87-96页

作者： Jiaqi ZHANG haihong tao Xiushe ZHANG Chunlei HAN State Key laboratory of Radar Signal Processing Xidian UniversityXi’an 710068China Xi’an Research Institute of Navigation Technology Xi’an 710071China

In this paper,a novel multi-frame track-before-detect algorithm is proposed,which is based on root label clustering to reduce the high computational complexity arising by observation area expansion and clutter/noise density increase.A criterion of track extrapolation is used to construct state transition set,root label is marked by state transition set to obtain the distribution information of multiple targets in measurement space,then measurement plots of multi-frame are divided into several clusters,and finally multi-frame track-before-detect algorithm is implemented in each cluster.The computational complexity can be reduced by employing the proposed algorithm.Simulation results show that the proposed algorithm can accurately detect multiple targets in close proximity and reduce the number of false tracks.

关键词： Multi-frame track-before-detect Multiple targets detection Root label clustering State transition set Track extrapolation

Quaternion based joint DOA and polarization parameters estimation with stretched three-component electromagnetic vector sensor array

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Journal of Systems Engineering and Electronics 2017年第1期28卷 1-9页

作者： Jichao Zhao haihong tao National Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China

The three-component electromagnetic vector sensor (EMVS) consisting of co-centered orthogonally oriented x-dipole, z-dipole and z-loop is considered. In order to make full use of the spatial aperture of each component, the original uniform linear three-component EMVS array (ULTEA) is stretched into one half-wavelength spaced uniform linear loop subarray (ULLSA) along the z axis, and one sparse uniform linear co-centered orthogonally oriented dual-dipole (CODD) subarray (SULCSA) along the x axis. Then, a generalized rotation invariance based quaternion multiple signal classification (GRIQ-MUSIC) algorithm is presented for direction of arrival (DOA) and polarization parameters estimation. According to the proposed algorithm, the elevation angles are firstly estimated based on the half-wavelength spaced ULLSA. Then the polarization phase differences and azimuth angles are obtained based on the coupling relationship between the angle domain and polarization domain, but the azimuth angles are in coarse-resolution since the array aperture is not utilized. Next, the SULCSA is used to re-estimate the azimuth angles in fine-resolution, and the ambiguity problem can be resolved by the least square method. Finally, based on the estimated elevation angles, azimuth angles and polarization phase differences, the corresponding auxiliary polarization angles can be estimated by N times one-dimensional parameter search, where N is the sources number, and the parameters are matched automatically. Based on the GRIQ-MUSIC algorithm, the high dimensional parameters search problem of the conventional Q-MUSIC algorithm is simplified to a one-dimensional parameter search problem, thus the proposed algorithm not only reduces the computation complexity considerably, but also avoids the performance degradation caused by the failure in parameters pairing. The simulation examples demonstrate the effectiveness and feasibility of the proposed algorithm. ? 1990-2011 Beijing Institute of Aerospace Information.

关键词： Computer music Direction of arrival Least squares approximations Polarization Wavelet analysis

Space-borne antenna adaptive anti-jamming method based on gradient-genetic algorithm

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Journal of Systems Engineering and Electronics 2007年第3期18卷 469-475页

作者： tao haihong Liao Guisheng Yu Jiang National Key Lab. of Radar Signal Processing Xidian Univ. Xi'an 710071 P. R. China

A novel space-borne antenna adaptive anti-jamming method based on the genetic algorithm （GA）, which is combined with gradient-like reproduction operators is presented, to search for the best weight for pattern synthesis in radio frequency （RF）. Combined, the GA＇s the capability of the whole searching is, but not limited by selection of the initial parameter, with the gradient algorithm＇s advantage of fast searching. The proposed method requires a smaller sized initial population and lower computational complexity. Therefore, it is flexible to implement this method in the real-time systems. By using the proposed algorithm, the designer can efficiently control both main-lobe shaping and side-lobe level. Simulation results based on the spot survey data show that the algorithm proposed is efficient and feasible.

关键词： space-borne antenna genetic algorithm （GA） gradient-like anti-jamming pattern synthesis.

Unveiling strain-enhanced moiréexciton localization in twisted van der Waals homostructures

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Nano Research 2024年第4期17卷 3245-3252页

作者： Henry Rui He haihong Zheng Biao Wu Shaofei Li Junnan Ding Zongwen Liu Jian-tao Wang Anlian Pan Yanping Liu Institute of Quantum Physics School of PhysicsCentral South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China School of Chemical and Biomolecular Engineering The University of SydneyNSW 2006Australia Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China College of Materials Science and Engineering Hunan UniversityChangsha 410082China State Key Laboratory of High-Performance Complex Manufacturing Central South UniversityChangsha 410083China Shenzhen Research Institute of Central South University Shenzhen 51800China

Moirésuperlattices,arising from the controlled twisting of van der Waals homostructures at specific angles,have emerged as a promising platform for quantum emission applications.Concurrently,the manipulation of strain provides a versatile strategy to finely adjust electronic band structures,enhance exciton luminescence efficiency,and establish a robust foundation for two-dimensional quantum light sources.However,the intricate interplay between strain and moirépotential remains partially unexplored.Here,we introduce a meticulously designed fusion of strain engineering and the twisted 2L-WSe_(2)/2L-WSe_(2) homobilayers,resulting in the precise localization of moiréexcitons.Employing low-temperature photoluminescence spectroscopy,we unveil the emergence of highly localized moiré-enhanced emission,characterized by the presence of multiple distinct emission lines.Furthermore,our investigation demonstrates the effective regulation of moirépotential depths through strain engineering,with the potential depths of strained and unstrained regions differing by 91%.By combining both experimental and theoretical approaches,our study elucidates the complex relationship between strain and moirépotential,thereby opening avenues for generating strain-induced moiréexciton single-photon sources.

关键词： moirésuperlattices strain engineering moiréexcitons moirépotential

单星定位中采用混沌映射的干扰源位置识别方法

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航空学报 2022年第7期43卷 335-346页

作者：张轶翟盛华陶海红中国空间技术研究院西安分院西安710100 西安电子科技大学雷达信号处理国家重点实验室西安710071

针对卫星通信中的连续大功率干扰定位问题,提出基于混沌映射的单星干扰源位置识别方法。该方法利用混沌振子的初值敏感性进行信号相关性分析,可有效降低卫星下行链路动态变化对上行链路的影响,进一步提升干扰源识别性能。通过对实测数... 详细信息

针对卫星通信中的连续大功率干扰定位问题,提出基于混沌映射的单星干扰源位置识别方法。该方法利用混沌振子的初值敏感性进行信号相关性分析,可有效降低卫星下行链路动态变化对上行链路的影响,进一步提升干扰源识别性能。通过对实测数据进行统计分析,结果表明不同混沌映射下,信号相关算法的复杂度和定位性能不同。在给定判决门限下,该定位模型可实现75%的干扰源识别概率,且定位成功率和定位精度分别达到65%和23 km,优于现有的量子衍生算法。

关键词：干扰源识别混沌映射单星定位信号相关卫星通信

FORECAST OF BREAKING LENGTH OF SIDE CURLING SHORT SPIRAL CHIPS

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Chinese Journal of Mechanical Engineering 1999年第4期12卷 297-302页

作者： Li Zhenjia Qu Guimin Xu Yihong tao haihong Department of Mechanical Engineering, Harbin University of Science and Technology 哈尔滨理工大学现代制造技术与刀具开发所黑龙江哈尔滨 150080 哈尔滨理工大学现代制造技术与刀具开发所黑龙江哈尔滨

The theoretical formula for estimating the side curling short spiral chips is simplified. On the basis of experiment, a practical formula for forecasting the chip breaking length is obtained. It is proved by experime... 详细信息

关键词： Side curling Short spiral chip Chip breaking