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24th International Vacuum Electronics Conference, IVEC 2023

作者： Zhou, Jinghan Ma, Chunguang Liu, Jiaming Yuan, Zhenqian Luo, Yong School of Electronic Science and Engineering University of Electronic Science and Technology of China Sichuan Chengdu610054 China State Key Laboratory of Electromagnetic Space Cognition and Intelligent Control Technology Beijing100089 China

ISBN: (纸本)9781665473217

With the development of gyrotron traveling wave amplifier, long-range high-resolution millimeterwave (MMW) imaging broadband radar has been developed rapidly. Nyquist theorem brings challenges to wideband radar signal sampling, and the hardware complexity and cost of the required equipment will increase significantly. Compression sensing (CS) takes advantage of the sparsity of the signal in the transformation domain. Under the condition that it is far less than Nyquist sampling rate, it uses random sampling to obtain discrete samples of the signal, and then perfectly reconstructs the signal through nonlinear reconstruction algorithm. This paper proposes a linear majorization sparsity adaptive matching pursuit (LMSAMP) algorithm based on CS theory. The LMSAMP algorithm with adaptive optimization step size selection is used to reconstructed two-dimensional image of wideband MMW radar. The imaging results show that LMSAMP algorithm has a good imaging effect. © 2023 IEEE.

关键词： Radar imaging

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Autonomous landing scene recognition based on transfer learning for drones

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Journal of Systems Engineering and Electronics 2023年第1期34卷 28-35页

作者： DU Hao WANG Wei WANG Xuerao WANG Yuanda School of Automation Southeast UniversityNanjing 210096China Autonomous Control Robot Laboratory Jiangsu Zhongke Institute of Applied Research on Intelligent Science and TechnologyChangzhou 213164China Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and TechnologyNanjing 210044China

In this paper, we study autonomous landing scene recognition with knowledge transfer for drones. Considering the difficulties in aerial remote sensing, especially that some scenes are extremely similar, or the same scene has different representations in different altitudes, we employ a deep convolutional neural network(CNN) based on knowledge transfer and fine-tuning to solve the problem. Then, LandingScenes-7 dataset is established and divided into seven classes. Moreover, there is still a novelty detection problem in the classifier, and we address this by excluding other landing scenes using the approach of thresholding in the prediction stage. We employ the transfer learning method based on ResNeXt-50 backbone with the adaptive momentum(ADAM) optimization algorithm. We also compare ResNet-50 backbone and the momentum stochastic gradient descent(SGD) optimizer. Experiment results show that ResNeXt-50 based on the ADAM optimization algorithm has better performance. With a pre-trained model and fine-tuning, it can achieve 97.845 0% top-1 accuracy on the LandingScenes-7dataset, paving the way for drones to autonomously learn landing scenes.

关键词： landing scene recognition convolutional neural network(CNN) transfer learning remote sensing image

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Follower Jamming to UAV FH Communication System Based on Simulink 24

Follower Jamming to UAV FH Communication System Based on Sim...

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24th International Vacuum Electronics Conference, IVEC 2023

作者： Li, Junhui Ma, Chunguang Zhao, Junyu Zhou, Jinghan Luo, Yong School of Electronic Science and Engineering University of Electronic Science and Technology of China Sichuan Chengdu610054 China State Key Laboratory of Electromagnetic Space Cognition and Intelligent Control Technology Beijing100089 China

ISBN: (纸本)9781665473217

With the vigorous rise of the unmanned aerial vehicle (UAV) market, the 'black flight' of UAVs has seriously threatened public safety, flight safety and even air defense safety. Therefore, the research of anti UAV technology is very urgent. The UAV is mainly equipped with the frequency-hopping (FH) communication system which has a strong anti-jamming capability. This paper establishes the structure diagram of the UAV FH communication system based on Simulink. And then the follower jamming of different power and interference dwell ratio (IDR) are set to interfere with the system respectively. We use the error rate to evaluate the interference effect of the model. The simulation results show that in the case of high jamming to signal ratio (JSR), follower jamming can effectively interfere with the UAV FH communication system. © 2023 IEEE.

关键词： Simulink

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A Multi-constrained Adaptive Predictor–Corrector Guidance Method for Ascent Phase of Hypersonic Vehicle

A Multi-constrained Adaptive Predictor–Corrector Guidance M...

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International Conference on Guidance, Navigation and control, ICGNC 2020

作者： Maomao, Li Jun, Hu Huang, Huang Ruike, Guo Beijing Institute of Control Engineering Beijing100190 China The Science and Technology on Space Intelligent Control Laboratory Beijing100190 China

ISBN: (纸本)9789811581540

In this paper, considering the various terminal states constraints, and coupling of different states in the ascent phase of the hypersonic aircraft, a multi-constrained guidance method based on predictor–corrector policy is proposed. Firstly, the dynamic equations of ascent phase are given. And then, the dynamic amplification factors for the various flight states are calculated. Analyzing the dynamic equations of ascent phase, it can be found that only the attack angle is used to control various states and the guidance of ascent phase is an under-driven problem. The path angles are small values at the terminal flight phase, and it has little couple influence on the altitude. In order to solve the under-driven problem, the whole ascent phase has two parts. At the initial phase, eliminating the terminal height error is chosen as the guidance object. At the terminal phase, eliminating the path angle error at the end point is chosen as the guidance object. What’s more, the influence of choosing different segmentation altitude on the terminal states errors is analyzed. Moreover, the Monte Carlo simulation demonstrates the effectiveness of the proposed multi-constrained adaptive predictor–corrector guidance method. © 2022, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Hypersonic vehicles

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Relative Position-Based Collaborative Navigation for Cluster UAVs 7th

Relative Position-Based Collaborative Navigation for Cluster...

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7th Chinese Conference on Swarm Intelligence and Cooperative control, CCSICC 2023

作者： Sheng, Danting Cheng, Jin Li, Fengyi Hao, Mingrui Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100074 China Aerospace Science and Industry Group Intelligent Technology Research Institute Co. Ltd. Beijing100074 China

ISBN: (纸本)9789819733316

The inertial equipment carried by UAVs without satellite signal assistance will accumulate errors over time, which cannot meet the requirement of obtaining high-precision cluster navigation information for cluster UAVs in long-duration flights. Aiming at this problem, a scheme for cooperative navigation of cluster UAVs based on relative position assistance is proposed. Firstly, the state equations of the cooperative navigation system are established by modeling the errors of inertial devices of low-precision UAVs;secondly, the relative position information of low-precision UAVs and high-precision UAVs as well as other low-precision UAVs transmitted between UAVs through the data chain is taken as the observation equation;finally, the inertial errors of low-precision UAVs are compensated by using the traceless Kalman filtering for the error compensation, which improves the navigation accuracy. After 30 min simulation results show that the cooperative navigation scheme converges the velocity and position errors of the low-precision UAV to 0.5 m/s and 5 m, respectively, which improves the navigation accuracy greatly. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Unmanned aerial vehicles (UAV)

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Prediction of Hybrid Asynchronous Frequency Hopping Pattern based on Deep Learning in Wideband Spectrum

Prediction of Hybrid Asynchronous Frequency Hopping Pattern ...

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2023 China Automation Congress, CAC 2023

作者： Wang, Ya Wang, Jiaqi Yuan, Shuai Liu, Naijin Lu, Yuanming Qian Xuesen Laboratory of Space Technology China Academy of Space Technology Beijing China Beijing Electro-Mechanical Engineering Institute Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing China Unit 63893 of Pla Luoyang China

ISBN: (纸本)9798350303759

In non-cooperative scenarios, wideband frequency hopping (FH) communication reconnaissance including FH signal detection, parameter estimation, and network sorting under single-channel reception is challenging. The FH pattern contains the most information about FH signals. So it is the core of FH parameter estimation. Based on the task analysis, this paper proposes a blind prediction framework combining deep learning (DL) and clustering methods to improve the accuracy and efficiency of FH pattern estimation for mixed signals in the wideband spectrum. The unique advantage of this framework is that it requires no prior signal information and anchors but exploits the inherent time-frequency (TF) properties of asynchronous FH signals. It has a strong generalization ability and can adapt to signals of any shape. Moreover, a new comprehensive evaluation metric, normalized root mean square error including missed detection (NRMSE-MD), suitable for sequence data prediction is proposed to evaluate the level of missed detection and false detection in signal monitoring. Experimental results demonstrate the superiority of the proposed framework and the effectiveness of the proposed evaluation metric. © 2023 IEEE.

关键词： Forecasting

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Active Disturbance Rejection control of Dense Medium Separation Process Based on Improved PI-GPC

Active Disturbance Rejection Control of Dense Medium Separat...

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2024 China Automation Congress, CAC 2024

作者： Zhao, Xiaoyao Zhou, Fan Zhao, Jun Wang, Wei Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of Education Dalian China School of Control Science and Engineering Dalian University of Technology Dalian China

ISBN: (纸本)9798350368604

Aiming at the complex field environment of dense medium separation process and the large amount of matrix inversion calculation in the traditional PI-GPC solution process, an adaptive stepped generalized predictive control method with proportional-integral structure (PI-ASGPC-LESO) based on active disturbance rejection strategy is proposed. Considering the large amount of calculation when PI-GPC solves the optimal control rate, an adaptive step factor dependent on the system adjustment error is introduced to constrain the change of the control amount, which reduces the amount of calculation in the solution process. In view of the complex on-site environment of dense medium separation and the large interference in the system, LESO is added to the loop to suppress external disturbances and compensate the unmodeled error of the system. In order to verify the effectiveness of the proposed method, a comparative experiment with traditional PI-GPC and PI-GPC-LESO was designed with the dense medium separation system of a coal preparation plant as the control object. The experimental results show that the proposed method effectively improves the dynamic performance of the system, with shorter adjustment time, smaller overshoot, and stronger anti-interference ability. © 2024 IEEE.

关键词： Disturbance rejection

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One-Shot Three-Dimensional Measurement Based on Spectral Interferometry Using a Digital Micromirror Device 16

One-Shot Three-Dimensional Measurement Based on Spectral Int...

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16th Pacific Rim Conference on Lasers and Electro-Optics, CLEO-PR 2024

作者： Zhang, Jinxu Shi, Liheng Gu, Yingying Zhang, Donglai Yin, Lu Wu, Guanhao Tsinghua University State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instrument Beijing100084 China Beijing Institute of Control Engineering Space Optoelectronic Measurement and Perception Lab. Beijing100190 China China Academy of Space Technology National Key Laboratory of Space Intelligent Control Beijing100094 China

We present a one-shot 3D spectral interferometry technique using a digital micromirror device. By encoding the distribution of the spatial light field, this approach enables 3D imaging of step structures within 27 ms.... 详细信息

ISBN: (纸本)9798350372076

关键词： Interferometry

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Adaptive Attitude control for a Coaxial Tilt-Rotor UAV via Immersion and Invariance Methodology

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IEEE/CAA Journal of Automatica Sinica 2022年第9期9卷 1710-1713页

作者： Longlong Chen Zongyang Lv Xiangyu Shen Yuhu Wu Xi-Ming Sun the Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education and the School of Control Science and EngineeringDalian University of TechnologyDalian 116024China

Dear Editor,This letter is concerned with the attitude control for a novel tiltrotor unmanned aerial vehicle with two pairs of tiltable coaxial rotors and one rear *** immersion and invariance-based adaptive attitude controller for the tilt-rotor unmanned aerial vehicle is *** the proposed control strategy,an adaptive update law is specially designed to compensate for the uncertainties of damping *** stability of the resulting closed-loop coaxial tiltrotor unmanned aerial vehicle(CTRUAV)system is proved by the Lyapunov methodology and LaSalle’s invariance ***。

关键词： theory. invariance letter

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High-performance chiral all-optical OR logic gate based on topological edge states of valley photonic crystal

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Chinese Physics B 2023年第7期32卷 392-398页

作者：王晓蓉费宏明林瀚武敏康丽娟张明达刘欣杨毅彪肖连团 College of Physics Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China School of Science RMIT UniversityMelbourneVictoria 3000Australia

For all-optical communication and information processing,it is necessary to develop all-optical logic gates based on photonic structures that can directly perform logic ***-optical logic gates have been demonstrated based on conventional waveguides and interferometry,as well as photonic crystal ***,any defects in those structures will introduce high scattering loss,which compromises the fidelity and contrast ratio of the information *** on the spin-valley locking effect that can achieve defect-immune unidirectional transmission of topological edge states in valley photonic crystals(VPCs),we propose a high-performance all-optical logic OR gate based on a VPC *** tuning the working bandwidth of the two input channels,we prevent interference between the two channels to achieve a stable and high-fidelity *** transmittance of both channels is higher than 0.8,and a high contrast ratio of 28.8 dB is ***,the chirality of the logic gate originated from the spin-valley locking effect allows using different circularly polarized light as inputs,representing“1”or“0”,which is highly desired in quantum *** device’s footprint is 18μm×12μm,allowing high-density on-chip *** addition,this design can be experimentally fabricated using current nanofabrication techniques and will have potential applications in optical communication,information processing,and quantum computing.

关键词： topological photonics topological edge state valley photonic crystal all-optical logic gate

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