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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Wen, Yongdiao Li, Gang Li, Tie Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an710065 China

ISBN: (纸本)9798350375909

Herein, a dual-functional terahertz (THz) metamaterial device is presented, the proposed device consists of two heteromorphic arrows, which can switch freely between absorption and polarization conversion controlled by a singular switch. The absorptivity peak (arounds 1.5 THz) and polarization conversion peak (arounds 2.8 THz) will be changed to polarization conversion peak and absorptivity peak with the state of the singular switch, the absorption function and the polarization conversion function can adjust and convert each other, and the maximum values of absorption rate and polarization conversion rate reach to 87.27% and 95.94% respectively. © 2024 IEEE.

关键词： Polarization

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Anti-jamming Method of FM Fuze Based on Deep Learning 4

Anti-jamming Method of FM Fuze Based on Deep Learning

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4th International Conference on Defence technology, ICDT 2024

作者： Zhang, Jin-Yu Yan, Xiao-Peng Hao, Xin-Hong Zhang, Jin-Cheng Science and Technology on Electromechanical Dynamic Control Laboratory China Beijing Institute of Technology China

In response to the challenges posed by sweeping jamming and Digital Radio Frequency Memory (DRFM) jamming in Frequency Modulation Continuous Wave (FMCW) fuzes, a jamming mitigation method based on deep learning method is proposed in this paper. Initially, the target beat frequency signal data affected by sweeping jamming and DRFM jamming is gathered and analysed using the Transformer method. A comparison is made between the classification and recognition outcomes of Transformer model and Support Vector Machine (SVM) methods to identify the optimal model. Subsequently, the feature information of the echo signal under interference is extracted using Empirical Mode Decomposition (EMD) decomposition, and the target features are reconstructed. Experimental results utilizing simulated data confirm that the proposed method achieves a classification accuracy of 92% and ensures that the fuze detonation distance remains within the pre-set 9 m range. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Support vector machines

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Research on detection performance of millimeter wave fuze under rainfall condition 4

Research on detection performance of millimeter wave fuze un...

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4th International Conference on Defence technology, ICDT 2024

作者： Tong, Ao Zhang, Yao Pan, Liwen Pan, Xi Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China

Aiming at the characteristics that the performance of millimeter wave fuze is easily affected by the natural environment, this paper studies the performance of millimeter wave fuze under rainfall conditions. By analyzing the theory of rain attenuation effect and backscattering effect, it is concluded that the rain attenuation effect reduces the received power of the signal, and the backscattering effect reduces the signal to interference plus noise ratio (SINR) of the receiving end. Based on this, the signal propagation path model under rainfall conditions is established. Finally, the variation of the maximum reliable detection range with signal wavelength and rainfall rate is simulated under different SINR requirements, and the variation of signal to noise ratio (SNR) and SINR with rainfall rate is compared under different distances. The simulation results show that both the rain attenuation effect and the backscattering effect lead to the decrease of the maximum reliable detection distance of millimeter wave fuze. With the increase of rainfall rate, the detection performance of millimeter wave fuze decreases, and the detection distance decreases by about 23.2 % under extreme conditions. The rain backscattering effect on millimeter wave fuze is higher than its attenuation effect, and the influence of rain backscattering effect on millimeter wave fuze increases with the increase of detection distance. When the detection distance increases from 15 m to 30 m, the difference between SNR and SINR at the receiving end of millimeter wave fuze increases by about 3 times. This study has important reference significance for the application of millimeter wave fuze in precision guided weapons. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Signal to noise ratio

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Design and Implementation of a Fuze Intermediate Frequency Echo Simulator System 4

Design and Implementation of a Fuze Intermediate Frequency E...

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4th International Conference on Defence technology, ICDT 2024

作者： Guo, Yao He, Shuhuan Yu, Wenheng Pan, Xi Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China

The fuse echo simulator plays a crucial role in fuse testing. This paper introduces a combined hardware and software solution for a fuze intermediate frequency (IF) echo simulation system. The system utilizes Direct Digital Synthesis (DDS) technology to generate controllable IF echo *** prestoring classic target and environmental characteristic information data, the system is capable of incorporating diverse target and environmental parameters during the simulation of projectile-target encounter process, thereby enhancing the fidelity of the simulated echo signals. Experimental simulations and engineering validations have confirmed that the proposed system can accurately simulate various characteristics of echo signals, while exhibiting low temporal complexity and high real-time performance. These attributes render it effective for evaluating the dynamic performance of Frequency Modulated Continuous Wave (FMCW) fuse systems. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Software testing

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Object Detection Based on Digital Twin-Based Road Scenarios 2

Object Detection Based on Digital Twin-Based Road Scenarios

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2nd IEEE International Conference on control, Electronics and Computer technology, ICCECT 2024

作者： Yu, Zhang Huimin, Chen Weihan, Wang Beijing Institute of Technology Science and Technology on Electromechanical Dynamic Control Laboratory Beijing100081 China

ISBN: (纸本)9798350380958

With the rapid development of artificial intelligence and digital technology, digital twins are becoming more and more widely used in various fields, and have high application value in industrial production, architectural design and other fields. There are few datasets of extreme scenarios used in traditional object detection and vehicle autonomous driving training, resulting in unsatisfactory results of object detection and autonomous driving technology in complex environments. In this paper, a digital twin model of the road scene is built based on the rules of City Engine and the Unreal Engine 4 platform, which can be used to build a model of complex road scenes and shorten the model construction cycle. Based on the constructed digital twin model, the target detection task is carried out, and it is verified that the target detection and autonomous driving tests can be carried out in the digital twin model. It provides ideas for solving the problem of insufficient testing of autonomous driving and object detection tasks in complex and extreme scenarios. © 2024 IEEE.

关键词： Object detection

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Air target recognition method against ISRJ for radio frequency proximity sensors using chaotic stream encryption

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Defence technology（防务技术） 2023年第10期28卷 267-279页

作者： Jian-feng Li Jian Dai Xin-hong Hao Xiao-peng Yan Xin-wei Wang Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing100081China BIT Tangshan Research Institute Beijing100081China

The interrupted-sampling repeater jamming(ISRJ)can cause false targets to the radio-frequency proximity sensors(RFPSs),resulting in a serious decline in the target detection capability of the *** article proposes a recognition method for RFPSs to identify the false targets caused by *** proposed method is realized by assigning a unique identity(ID)to each RFPS,and each ID is a periodically and chaotically encrypted in every pulse *** processing technique of the received signal is divided into ranging and ID *** the ranging part,a high-resolution range profile(HRRP)can be obtained by performing pulse compression with the binary chaotic *** suppress the noise,the singular value decomposition(SVD)is applied in the *** ID decryption,targets and ISRJ can be recognized through the encryption and decryption processes,which are controlled by random *** adaptability analysis conducted in terms of the peak-to-side lobe ratio(PSLR)and bit error rate(BER)indicates that the proposed method performs well within a 70-k Hz Doppler shift.A simulation and experimental results show that the proposed method achieves extremely stable target and ISRJ recognition accuracies at different signal-to-noise ratios(SNRs)and jamming-to-signal ratios(JSRs).

关键词： Interrupted-sampling repeater jamming(ISRJ) Radio frequency proximity sensors(RFPS) Chaotic stream encryption Air target recognition Identity(ID)decryption

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Adaptive target and jamming recognition for the pulse doppler radar fuze based on a time-frequency joint feature and an online-updated naive bayesian classifier with minimal risk

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Defence technology（防务技术） 2022年第3期18卷 457-466页

作者： Jian Dai Xin-hong Hao Ze Li Ping Li Xiao-peng Yan Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing100081China

This paper considers the problem of target and jamming recognition for the pulse Doppler radar fuze(PDRF).To solve the problem,the matched filter outputs of the PDRF under the action of target and jamming are ***,the frequency entropy and peak-to-peak ratio are extracted from the matched filter output of the PDRF,and the time-frequency joint feature is *** on the time-frequency joint feature,the naive Bayesian classifier(NBC)with minimal risk is established for target and jamming *** improve the adaptability of the proposed method in complex environments,an online update process that adaptively modifies the classifier in the duration of the work of the PDRF is *** experiments show that the PDRF can maintain high recognition accuracy when the signal-to-noise ratio(SNR)decreases and the jamming-to-signal ratio(JSR)***,the applicable analysis shows that he ONBCMR method has low computational complexity and can fully meet the real-time requirements of PDRF.

关键词： Pulse Doppler radar fuze(PDRF) Target and jamming recognition Time-frequency joint feature Online-update naive Bayesian classifier minimal risk(ONBCMR)

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Research on dynamic response behavior of the fuze with a combined fuze-warhead structure under different impact positions of bullets 4

Research on dynamic response behavior of the fuze with a com...

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4th International Conference on Defence technology, ICDT 2024

作者： Wang, Qiang Niu, Lanjie Fan, Chenyang Qv, Zhuojun Xv, Rui Science and Technology on Electromechanical Dynamic Control Laboratory Xi’an Institute of Electromechanical Information Technology Xi’an China

Aiming at the problem of unclear fuse detonation response in the process of different positions of the bullet impact detonator, to carry out research on the dynamic response behaviour of the fuse under the difference of the bullet impact position of the fuze-warhead combination structure. Through experiments and LS-DYNA numerical simulation, the influence of different positions of bullet impact booster on fuze reaction level and output pressure is analyzed. The results demonstrate that in the tests where the bullet made contact with the centre of the fuse, transmitting an explosive charge, the velocity of the bullet is 832 m/s, and the fuse exhibits a partial detonation level in response to the impact. The highest fuse response level occurs when the bullet strikes the centre of the pyrotechnic charge - partial detonation, the lowest fuse response level occurs when the bullet strikes the upper side of the pyrotechnic charge - burning, and the fuse response level occurs when the bullet strikes the lower side of the pyrotechnic charge - deflagration or explosion. The maximum fuse output pressure when the bullet strikes the centre of the pyrotechnic charge - 6.09 GPa, the minimum fuse output pressure when the bullet strikes the upper side of the pyrotechnic charge - 0.98 GPa, and the fuse output pressure when the bullet strikes the lower side of the pyrotechnic charge is 2.76 GPa. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Detonation

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Application of 3D Gaussian Splatting target Reconstruction in short-range detection 4

Application of 3D Gaussian Splatting target Reconstruction i...

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4th International Conference on Defence technology, ICDT 2024

作者： Lou, Wenzhong Li, Chenglong Feng, Hengzhen Ding, Nanxi Zhang, Zihao Ma, Wenlong Wang, Lin Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical Engineering Beijing Institute of Technology Beijing China

The research presented in this paper successfully introduces the emerging 3D reconstruction technology to specific application scenarios, especially for the strict requirements of information authenticity and timeliness for reconnaissance equipment and platforms. Traditional methods have the problems of slow speed and damaged reconstruction quality in processing reconnaissance information. In order to solve the problem of limited computing power of aerial detection platform and improve the reconstruction quality and efficiency of complex scenes, this paper introduces three-dimensional Gaussian Splatting (3DGS) method for testing. Experimental results show that 3DGS has excellent performance in rendering accuracy and real-time performance, which can effectively meet the performance requirements of aerial detection platforms. We tested it on a virtual dataset, and the experimental results show that it can also maintain excellent performance in the real world. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： 3D modeling

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Orthogonal simulation and experimental study on SLM process parameters for micro-sized high dynamic components 4

Orthogonal simulation and experimental study on SLM process ...

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4th International Conference on Defence technology, ICDT 2024

作者： Lv, Sining Lou, Wenzhong Feng, Hengzhen Xiao, Chuan Li, Shiyi Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical Engineering Beijing Institute of Technology Beijing China

Metal Additive Manufacturing (MAM) technology has become an important means of rapid prototyping of special high dynamic complex components. This study employs selective laser melting (SLM) as a technological approach for investigating micro-sized high dynamic components. The parameters that affect SLM process are analysed, mainly including laser power, laser speed, laser diameter, and scan spacing. Based on prior studies, feasible parameter ranges are identified, and an orthogonal experimental design table is established for simulation and experimental co-verification. Range and variance analysis are conducted and the influence ability of each influencing factor is explored from both simulation and experimental aspects. The SLM process model is established using finite element software, taking into account parameters such as residual stress and maximum deformation. The conclusion is drawn that the order of influence of each factor on the preparation of micro-sized high dynamic components is: scan spacing>laser power>laser diameter> laser speed. Samples of components are fabricated and subjected to static testing. The density of the components can reach over 99.15%, and the structural strength can reach 348 MPa, which meet the required standards and confirm the simulation analysis. The results demonstrates that SLM provides a novel manufacturing method for micro-sized high dynamic components. © 2024 Published under licence by IOP Publishing Ltd.

关键词： Selective laser melting

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