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9th International Conference on Environmental and Engineering Geophysics, ICEEG 2020

作者： Wang, Ying Feng, Xuan Liang, Wenjing Zhou, Haoqiu Dong, Zejun Li, Xiaotian Xue, Cewen College of Geo-Exploration Science and Technology Jilin University No.938 Xi Min Zhu Street Changchun China Science and Technology on Near-Surface Detection Laboratory Wuxi China Institute of National Development and Security Studies Jilin University No.2699 Qianjin Street Changchun China No.938 XiMin Zhu Street Changchun China

The water ice exploration mission is an important scientific target of China's first Mission to Mars. The high frequency full polarimetric subsurface penetrating radar (SPR) system onboard the landing rover can carry out high-resolution imaging of the near-surface area of Mars, which is an important tool for detecting the presence of shallow water ice and soil structure. At present, most of the radar detection simulations are based on low-frequency antennas to analyze the geological structure of Mars down to several kilometers, with low resolution, which is difficult to detect the subsurface structure in the near-surface accurately. Considering topographic relief, interface roughness, subsurface rock, water ice, and permittivity changes at different layers, a three-dimensional near-surface model in the Isidis Planitia on Mars is established. The interpretation of the forward simulation results is of reference value for future Mars exploration missions. © Published under licence by IOP Publishing Ltd.

关键词： Rovers

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A 3d Non-Stationary Geometry-Based Stochastic Model for Uav Air-to-Ground Mimo Channels

SSRN

引用

SSRN 2022年

作者： Zhou, Tianxiang Yan, Feng Li, Hao Pang, Jingming Ding, Kai Xia, Weiwei Shen, Lianfeng National Mobile Communications Research Laboratory Southeast University Nanjing210096 China Science and Technology on Near-Surface Detection Laboratory Wuxi214035 China Jiangsu ZhongLi Electronic Information Sci-Tech Co. Ltd Changshu215542 China

In this paper, a three-dimensional geometry-based stochastic model is proposed for unmanned aerial vehicle (UAV) non-stationary air-to-ground multi-input multi-output (MIMO) channels. In the proposed model, the scatterers around the UAV and ground station are assumed to be distributed on the surface of two cylinders respectively. In order to describe the channel non-stationarity, the impact of rotations and accelerated motion of UAV are taken into account. The computation method of the corresponding time-variant parameters are theoretically deduced, including UAV antenna array angles, time delays and maximum Doppler frequencies. Based on the model, the channel statistical properties such as space-time correlation functions are further derived. Simulation results show that the increasing accelerations of the UAV and ground station can reduce the time correlation function and increase the channel non-stationarity in time domain. The UAV rotation has an important influence on the spatial correlation function, and the influence of rolling is more significant than that of pitching. © 2022, The Authors. All rights reserved.

关键词： Unmanned aerial vehicles (UAV)

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Calibration of Interface Induced Polarization for Full Polarimetric Ground Penetrating Radar 9

Calibration of Interface Induced Polarization for Full Polar...

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9th International Conference on Environmental and Engineering Geophysics, ICEEG 2020

作者： Dong, Zejun Feng, Xuan Liu, Cai Liang, Wenjing Zhou, Haoqiu College of Geo-Exploration Science and Technology Jilin University No.938 Xi MinZhu Street Changchun China Institute of National Development and Security Studies Jilin University No.2699 Qianjin Street Changchun China Science and Technology on Near-Surface Detection Laboratory Wuxi China No.938 Xi MinZhu Street Changchun China

The traditional ground penetrating radar (GPR) uses only one type of antenna for data acquisition, and only obtains single polarization data of targets. It can not fully describe the various properties of the target. Full polarimetric GPR is a new technology that uses four different polarization antennas to measure the target and can receive electromagnetic waves of different polarized directions to describe the polarization effect of targets. However, when the plane electromagnetic wave propagates through the ground surface, the polarized direction will rotate, namely interface induced polarization (IIP), which results in the complex interference embedded in the full polarimetric GPR data. In this research, firstly we discuss the generation of the IIP;subsequently how the IIP affect the full polarimetric GPR data is derived;finally the calibration formula is proposed and is applied to the GPR data processing. © Published under licence by IOP Publishing Ltd.

关键词： Ground penetrating radar systems

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Speckle suppression of SAR image using boundary and contextual constraint 5

Speckle suppression of SAR image using boundary and contextu...

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IET International Radar Conference 2020, IET IRC 2020

作者： Yuming, Wang Chaopeng, Luo Tian, Jin Yansong, Zhang College of Information Science and Engineering Hunan Normal University Changsha China Science and Technology on Near-Surface Detection Laboratory Wuxi China College of Electronic Science and Technology National University of Defense Technology Changsha China

ISBN: (纸本)9781839535635

Speckle suppression is a important preprocessing step for synthetic aperture radar (SAR). In this paper, a speckle suppression algorithm based boundary and contextual constraint is studied for enhancing image, which includes the establishment of speckle model based on boundary constraint, the analysis of speckle factor weighted constraint model based on contextual regularization, and the process of speckle factor estimation. The performance of this algorithm is validated by using the data acquired over an airship mounted SAR system. © 2020 Institution of Engineering and technology. All rights reserved.

关键词： Speckle

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Design and Implementation of Real-Time Localization System (Rtls) Based on Uwb and Tdoa Algorithm

SSRN

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SSRN 2022年

作者： Zhang, Fengyun Yang, Li Liu, Yuhuan Ding, Yulong Yang, Shuang-Hua Li, Hao Department of Computer Science and Engineering Southern University of Science and Technology Shenzhen China Army Engineering University PLA Nanjing China Academy for Advanced Interdisciplinary Studies Southern University of Science and Technology Shenzhen China PCL Research Center of Networks and Communications Peng Cheng Laboratory Shenzhen China Science and Technology on Near-surface Detection Laboratory Wuxi China

Nowadays, accurate localization plays an essential role in many fields, like target tracking and path planning. The challenges of indoor localization include inadequate localization accuracy, unreasonable anchor deployment in complex scenarios, lack of stability, and the high cost. So the universal positioning technologies cannot meet the real application requirements scarcely. To overcome these shortcomings, a comprehensive Ultra Wide-Band (UWB) based RTLS is presented in this paper. We introduce the architecture of real-time localization system, then propose a new wireless clock synchronization (WCS) scheme, finally discuss the time difference of arrival (TDoA) algorithm. We define the time-base selection strategy for the TDoA algorithm, and analyze the relationship between anchor deployment and positioning accuracy. The Extended Kalman Filter (EKF) method is presented for non-linear dynamic localization estimation, and it performs well in terms of stability and accuracy in moving target. © 2022, The Authors. All rights reserved.

关键词： Extended Kalman filters

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Electromagnetic radiation analysis and synthesize of UAV target with the theory of characteristic modes 5

Electromagnetic radiation analysis and synthesize of UAV tar...

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IET International Radar Conference 2020, IET IRC 2020

作者： Chen, Yu Wang, Yizhao Tang, Qi Zhou, Haosu Wang, Yan Science and Technology on Near-Surface Detection Laboratory China School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing China Shanghai Spaceflight Electronic and Communication Equipment Research Institute China

ISBN: (纸本)9781839535635

The theory of Characteristic Modes can better express the physical concept of radiator. In this paper, a fast method for synthesizing the radiation pattern of an unmanned aerial vehicle (UAV) platform is presented based on the characteristic mode theory. We can synthesize specific radiation patterns of the target to reduce or increase radiation energy in specific directions. © 2020 Institution of Engineering and technology. All rights reserved.

关键词： Unmanned aerial vehicles (UAV)

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Root inspired in situ interlocked interface for strength and ductility combination of refractory high-entropy alloys/Ni composites by activated sintering

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Materials science and Engineering: A 2025年 939卷

作者： Yang, Xiao Yang, De Huang, Hai Wang, Shubang Zhang, Zehai Liang, Zhimin Wang, Liwei Peng, Zhenzhen Liu, Ying Wang, Dianlong Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and Engineering Hebei University of Science and Technology Shijiazhuang050018 China School of Materials Science and Engineering East China Jiaotong University Nanchang330013 China Key Laboratory of Superlight Material and Surface Technology Ministy of Education College of Materials Science and Chemical Engineering Harbin Engineering University Harbin150001 China School of Mechanical Engineering Yanshan University Qinhuangdao066004 China

This work proposed a simple bionic-inspired strategy to in situ construct a root-like interfacial interlocked structure in the refractory high-entropy alloys (RHEA) particle-reinforced Ni matrix composites by activated sintering. The results showed that at the RHEA-Ni interface, Ni element preferred to aggregate inside the RHEA near the interface by grain boundaries (GBs) wetting and far away from the interface by GBs prewetting. Subsequently, the Ni-rich liquid-like film crystallized into Ni3(Ta, Nb), Ni2(Ta, Nb) phases due to relatively low Gibbs free energy change (ΔG) and high diffusion rate, in situ forming root-like interlocked structure anchored on the RHEA particle. At the root-like interlocked interface, the Ni-Ta intermetallic compounds (IMCs) and BCC phase, serving as alternating hard and soft oriented phases, enhance the interlocked interface hardness and elastic modulus. The finite element method proved that the root-like interlocked structure reduced the demand for interfacial reaction layer strength and the degree of interfacial stress concentration. Compared to the pure Ni bulk, the 10 vol% RHEA/Ni composite obtains 41.8 % and 93.4 % in ultimate tensile strength (UTS) to 509 MPa and yield strength (YS) to 205 MPa, respectively, while maintaining an acceptable elongation of 15.8 %. This work offers a novel approach to in situ synthesize the bionic configuration interface structure for the enhanced interfacial bonding and optimized interfacial stress distribution of the Ni matrix composites. © 2025 Elsevier B.V.

关键词： Tensile strength

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PCA applied to Data Fusion for Subsurface Target Imaging of Full-polarimetric GPR 9

PCA applied to Data Fusion for Subsurface Target Imaging of ...

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9th International Conference on Environmental and Engineering Geophysics, ICEEG 2020

作者： Xue, Cewen Feng, Xuan Zhou, Haoqiu Li, Xiaotian Liang, Wenjing Wang, Ying College of Geo-Exploration Science and Technology Jilin University No.938 Xi MinZhu Street Changchun130026 China Science and Technology on Near-Surface Detection Laboratory Wuxi214035 China Institute of National Development and Security Studies Jilin University No.2699 Qianjin Street Changchun130012 China No.938 Xi MinZhu Street Changchun130026 China

Full-polarimetric ground penetrating radar (GPR) can obtain more comprehensive polarization data (called VV, HH, VH) for the same target than traditional commercial radar (only VV). We need to use data fusion technology to combine the polarization information of the three different polarization modes. However, the full-polarimetric GPR data fusion method has one weighted average fusion, which will mask the advantages of full polarization. Principal component analysis (PCA) is a technology of data dimensionality reduction and compression which can use VV, HH and VH as a three-dimensional data to conduct data dimensionality reduction and find the best data fusion results. In order to check the reliability, we obtained the full-polarimetric GPR data of three typical targets in the laboratory for analysis. Then we compare PCA with the weighted average fusion method by using the instantaneous amplitude and conclude that PCA can fuse full-polarimetric GPR data better than weighted average fusion. © Published under licence by IOP Publishing Ltd.

关键词： Principal component analysis

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A full-polarimetric GPR system and its application in ice crack detection 9

A full-polarimetric GPR system and its application in ice cr...

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9th International Conference on Environmental and Engineering Geophysics, ICEEG 2020

作者： Li, Xiaotian Feng, Xuan Liang, Wenjing Xue, Cewen Zhou, Haoqiu Wang, Ying College of Geo-Exploration Science and Technology Jilin University No.938 Xi Min Zhu Street Changchun130026 China Science and Technology on Near-Surface Detection Laboratory Wuxi214035 China Institute of National Development and Security Studies Jilin University No.2699 Qianjin Street Changchun130012 China No.938 Xi Min Zhu Street Changchun130026 China

The warming season of Antarctica, where sea ice melts and breaks, is often the golden time for Antarctic research. But this season is also a high frequency season for the formation of ice crack, the existence of which poses a serious threat to Antarctic scientific research. Therefore, it is of important significance to monitor the trend, location, and depth of Antarctic sea ice crack in real time. Ice crack detection often uses ground penetrating radar (GPR) technology. Compared with the single-polarimetric GPR, full-polarimetric GPR can obtain more comprehensive polarization information. Therefore, a full-polarimetric GPR system based on the horn antenna is built in this paper to obtain more abundant ice crack information. Then we apply it to detect a small-scale ice crack atop frozen lakes. The analysis of the experiments and data fusion processing results can verify the effectiveness of the system for the detection of ice crack and lay the foundation for subsequent actual detection. © Published under licence by IOP Publishing Ltd.

关键词： Ground penetrating radar systems

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Exploiting More Information in Sparse Point Cloud for 3D Single Object Tracking

arXiv

引用

arXiv 2022年

作者： Cui, Yubo Shan, Jiayao Gu, Zuoxu Li, Zhiheng Fang, Zheng The Faculty of Robot Science and Engineering Northeastern University Shenyang110819 China The Science and Technology Near-Surface Detection Laboratory Wuxi214000 China The National Frontiers Science Center for Industrial Intelligence and Systems Optimization Shenyang110819 China The The Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Ministry of Education Shenyang110819 China

3D single object tracking is a key task in 3D computer vision. However, the sparsity of point clouds makes it difficult to compute the similarity and locate the object, posing big challenges to the 3D tracker. Previous works tried to solve the problem and improved the tracking performance in some common scenarios, but they usually failed in some extreme sparse scenarios, such as for tracking objects at long distances or partially occluded. To address the above problems, in this paper, we propose a sparse-to-dense and transformer-based framework for 3D single object tracking. First, we transform the 3D sparse points into 3D pillars and then compress them into 2D bird's eye view (BEV) features to have a dense representation. Then, we propose an attention-based encoder to achieve global similarity computation between template and search branches, which could alleviate the influence of sparsity. Meanwhile, the encoder applies the attention on multi-scale features to compensate for the lack of information caused by the sparsity of point cloud and the single scale of features. Finally, we use set-prediction to track the object through a two-stage decoder which also utilizes attention. Extensive experiments show that our method achieves very promising results on the KITTI and NuScenes datasets. Code is available at https://***/3bobo/smat. © 2022, CC BY.

关键词： Signal encoding

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