检索结果-内蒙古大学图书馆

Asian and Pacific Conference on Synthetic Aperture Radar (APSAR)

作者： Ying Zhang Wei Xiong Xichao Dong Cheng Hu Chengxiang Liu Yang Sun Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China School of Information and Electronics Beijing Institute of Technology Beijing China

ISBN: (数字)9781728129129

ISBN: (纸本)9781728129136

In some case, the azimuth spectrum bandwidth is larger than the pulse repetition frequency (PRF), leading to a whole azimuth spectrum has been folded into multiple subsegments and aliased. Therefore, the traditional Doppler ambiguous integer estimation method cannot be used directly. In this paper, the influence of Doppler ambiguous integer on residual range migrations' slope is analyzed. Based on the slope, the Doppler ambiguous integer estimation method for moving targets with azimuth spectrum aliasing is given. From the simulation results, the Doppler ambiguous integer can be estimated accurately by proposed method.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A Novel Geosynchronous Spaceborne-Airborne Bistatic Multichannel Sar For Ground Moving Targets Indication

A Novel Geosynchronous Spaceborne-Airborne Bistatic Multicha...

引用

IEEE International Symposium on Geoscience and Remote Sensing (IGARSS)

作者： Xichao Dong Wei Xiong Ying Zhang Cheng Hu Feifeng Liu School of Information and Electronics Beijing Institute of Technology Beijing China Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China

Geosynchronous synthetic aperture radar (GEO SAR) has great potentials in synthetic aperture radar ground moving target indication (SAR-GMTI) due to its high time resolution and wide swath coverage. But the signal-to-noise ratio (SNR) of echo is too low and multichannel configuration cannot be realize in GEO monostatic SAR. Therefore, geosynchronous spaceborne-airborne bistatic multichannel synthetic aperture radar (GEO-SABM SAR) can realize enhanced SNR and multichannel configuration. In this paper, we establish the slant range model for GEO-SABM SAR and give the VSAR processing flowchart. Finally, the numerical experiments is given to verify the effectiveness of proposed method.

关键词： Synthetic aperture radar Clutter Doppler effect Imaging Flowcharts Orbits Remote sensing

来源：评论

学校读者我要写书评

暂无评论

A location method for ground moving target with azimuth spectrum aliasing in Geosynchronous Spaceborne-Airborne Bistatic multichannel SAR

A location method for ground moving target with azimuth spec...

引用

Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Ying Zhang Wei Xiong Xichao Dong Cheng Hu Chengxiang Liu Yang Sun Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China Key Laboratory of Electronic and Information Technology in Satellite Navigation (Beijing Institute of Technology) Ministry of Education Beijing China

ISBN: (数字)9781728123455

ISBN: (纸本)9781728123462

Geosynchronous Spaceborne-Airborne Bistatic multichannel SAR (GEO-SABM SAR) maintains the fine temporal sampling and wide coverage characteristics of monostatic GEO SAR. But due to the PRF of GEO platform is very low, azimuth spectrum aliasing (ASA) will occur in GEO-SABM SAR which will make a moving target divided into several sub-targets. In this paper, a location method for ground moving target with ASA has given. From the simulation results, the moving target can be discriminated and located.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Generation framework for situation visualization service from the perspective of cognition 3

Generation framework for situation visualization service fro...

引用

3rd IEEE International Conference on Data science in Cyberspace, DSC 2018

作者： Yang, Fande Qiang, Li Science and Technology on Complex Electronic System Simulation Laboatory Space Engineering University Beijing China

ISBN: (纸本)9781538642108

The misunderstanding of situation system developers and users leads to the low efficiency of the technology to apply. With three perspectives of cognition as systematicness, subjectivity and interactivity, the functions and coupling relationships of the components of situational cognition system are studied. The interaction between the cognitive subjects and the situation servers is focused on. The generation framework of situation visualization service is proposed, and the cognition demands and application orientation of each link are analyzed. The service mode of situation visualization is discussed. It provides channels for situation processing and visualization technologies to be applied effectively, and for situational data to be used efficiently. © 2018 IEEE.

关键词： Visualization

来源：评论

学校读者我要写书评

暂无评论

Better Modeling the Hierarchical Structure of Language for Sentence Semantic Matching

引用

Journal of Physics: Conference Series 2020年第1期1651卷

作者： Zhongmin Pei Changqun Li Wei Xiong Zhangkai Luo Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing 100014 China

Sentence semantic matching requires understanding the semantic relationship between two sentences, which is widely used in various natural language tasks such as paraphrase identification, natural language inference and question answering. Usually, the underlying structure of sentence is not strictly sequential, this structure is hierarchical. This paper studies how to better model the hierarchical structure of sentence for semantic matching. Recent research suggests that BERT implicitly captures classical, tree-like structures. Based on this, this paper proposes to further enhance the strength of modeling hierarchical structure of language with an advanced variant of LSTM – Ordered Neurons LSTM(ON-LSTM), which introduces a syntax-oriented inductive bias to perform the composition of classical tree structure. Experimental results demonstrate that the proposed approach, which enhances hierarchical structure of language, significantly improves the performance of sentence semantic matching.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Research on vulnerability of space information network based on interdependent networks 3

Research on vulnerability of space information network based...

引用

3rd IEEE International Conference on Data science in Cyberspace, DSC 2018

作者： Zhao, Zhongwen Li, Zhangyuan Guo, Huanghuang Yang, Miaoben Space Engineering University Science and Technology On Complex Electronic System Simulation Laboratory Beijing China 63710 troops Taiyuan China

ISBN: (纸本)9781538642108

With the development and growing applications of information technology, the coupling and dependency of space information network are becoming more and more intense. In this paper, the vulnerability of space information network coupled with the communication network and function network is studied. Aiming at the shortage of traditional attack model, we put forward physical-attack and cyber-attack and set up different attack strategies such as random attack, targeted attack and gray attack. The concept of combat component is proposed and the cascading failure algorithm is given. The simulation shows that compared with traditional single network model, the interdependent network model based on the combat component can more accurately reflect the cascading failure mechanism of the space information network. This research results can provide guidance for space information network security research and invulnerability design. © 2018 IEEE.

关键词： Network security

来源：评论

学校读者我要写书评

暂无评论

Design and modeling of satellite network structure for business scenarios

引用

Journal of Physics: Conference Series 2020年第1期1684卷

作者： Lintao Ren Zhongmin Pei Wei Xiong Zhangkai Luo Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing 101416 China

In view of the actual decentralized development of the satellite service constellation and the trend of space-ground integrated information network, based on the idea of clustering, methodology of complex network community structure, a business scenario-oriented satellite network structure is designed. On the one hand, it reflects the different separation and integration of satellite constellations in business scenarios. On the other hand, the 'head node' mechanism is introduced to be responsible for the interaction between constellation in different business scenarios. The satellite network structure is modeled using the growth and priority connection mechanism, and through computational derivation and simulation validation, the scale-free characteristics of the satellite network are revealed. Finally, through the simulation experiments on different satellite network parameters, the effect of different parameters on the static geometry, network efficiency, etc., are obtained. The influence of the law of the network will provide theoretical and methodological reference for the design of satellite network structure.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Researchment of Mainlobe Anti-jamming Algorithms

引用

Journal of Physics: Conference Series 2020年第1期1673卷

作者： Zhangkai Luo Zhongmin Pei Yinan Li Xinmin Wang Bo Zou Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing 101400 China.

Main lobe interferences usually cause the distortion and peak offset of main lobe and the heighten of side lobe level in adaptive beamformers. The block matrix algorithm utilized the direction vector which was determined by both the antenna arrays and the direction of interference to eliminate the main lobe interference. But this algorithms is sensitive to the error occurred in the interference arrive angle and would consume the array of degrees of freedom. In this paper a new algorithm is proposed which projects the receive signal into a space which is orthogonal to the signal subspace to achieve the goal. The space can get by three steps. Frist we obtain eigenvalues by the decomposition of the covariance matrix of the snapshots to evaluate the noise power. Then we get a new matrix by removing the noise from the covariance matrix of the snapshots. At last we get the target space by conducting the singular value decomposition to the new matrix. Performance is mainly assessed in terms of the beamforming gain and the signal to interference and noise (SINR) ratio. The computer simulation shows the effective of this method.

关键词：

来源：评论

学校读者我要写书评

暂无评论

The Architecture of Digital system Model for systems-of-systems Engineering

The Architecture of Digital System Model for Systems-of-Syst...

引用

Chinese Automation Congress (CAC)

作者： Xinghai Gao Yaqi Zhang Zhuoqi Wang Institute of Unmanned System Beihang University Beijing China Science and Technology on Complex Systems Simulation Laboratory Beijing China

The rapid increasing challenges of modeling and simulation for systems-of-systems Engineering (SoSE) is to deal with their large-scale and complexity of heterogeneous and inter-dependent constituent systems. Typically, the method of structural modeling provides a thorough understanding of the composition and operation of different elements, but loses sight of the dynamic characteristics of the systems or components. To make a comprehensive analysis of the system-of-systems (SoS), the solution of behavior modeling will be more important to adapt to the evolving of the SoS, which focus on understanding the constituent systems and their relationships, and evaluating changes of the constituent system, and continuously responding to the new requirements and options of SoS. This paper discusses how to support the application of modeling and simulation (M&S) based on the framework of SysML to describe the architecture and capability of SoS, and combined with the process and activities of model-based system engineering (MBSE).

关键词： Unified modeling language Object oriented modeling Analytical models Digital systems Adaptation models

来源：评论

学校读者我要写书评

暂无评论

Data compression method based on information preservation for wideband radar LFM signal echo

Data compression method based on information preservation fo...

引用

IET International Radar Conference 2018, IRC 2018

作者： Gao, Lei Zeng, Yong-Hu Wang, Lian-Dong Wang, Wei State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System Luoyang471003 China College of Electronic Science National University of Defense Technology Changsha Hunan410073 China

With the increase of radar signal bandwidth and the application of RF directing sampling technology, wideband radars are facing greater pressures for data transmission, storage, and processing. Based on the relationship between linear frequency modulation (LFM for short) signal and LFM-stepped signal, synthesis method of high-resolution range profile (HRRP for short) for LFM step signal can be applied to LFM signal. Combining the synthesis method of HRRP for LFM signal with compressed sensing theory, this study proposes a new compression method for wideband radar echo with LFM signal style based on random segment selection and analyses the constraint conditions of the proposed data compression method. Finally, the validity and practicability of the proposed data compression method are verified from two aspects: simulation experiment and actual data processing. © 2019 Institution of Engineering and technology. All rights reserved.

关键词： Data compression

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：