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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Zhang, Kuo Xie, Jiahao Liu, Zhenyang Yu, Songtao Science and Technology on Electronic Information Control Laboratory China

ISBN: (纸本)9798350375909

In this paper, a type of low cross polarization phased antenna arrays for X-band spaceborne synthetic aperture radar (SAR) applications is presented. The horizontal polarization radiation performance is realized with ridged-waveguide longitudinal slotted antenna arrays. The arrays are divided into several subarrays according to the scanning requirements of the phased array antennas, and V type slot is employed in ridged-waveguide wide wall as radiation unit. Excellent capacities such as matching characteristics, high efficiency and low cross polarization are achieved by adjusting the penetration angle and depth of the V slot. In the azimuth direction, the slotted waveguide antenna is designed as a linear array, and the low profile characteristics of antenna is realized by adopting stereoscopic coupling feeding technology. In the range direction, the narrow-wall dimensions of the ridged-waveguide is compressed by the ridged-waveguide to optical-waveguide mode conversion technology, and the preferable grating lobe performance is assured. A panel of 10 × 32 ridged-waveguide slotted antenna arrays with the active transceiver module are designed and fabricated, which are composed with 10 subarrays in azimuth direction and 32 subarrays in range direction, and each subarray contains 20 V slotted radiators, the total size of the phased antenna arrays is 121.6λ0 × 23.4λ0. The measured result shows a good agreement with the designed and calculated values, the normal efficiency exceeds 80% and the cross polarization level is lower than -30 dB in working band-with, and the modular design and compact structure, it is suitable for sapceborne SAR system, and the arrays in orbit is in good use. © 2024 IEEE.

关键词： Antenna phased arrays

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A High-gain 3D-printed Phased Array Antenna for Satellite Applications

A High-gain 3D-printed Phased Array Antenna for Satellite Ap...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Xie, Jiahao Zhang, Kuo Zuo, Le Science and Technology on Electronic Information Control Laboratory China

ISBN: (纸本)9798350375909

In this paper, a high-gain 3d-printed phased array antenna is proposed for satellite applications. A multi-mode horn antenna is designed as the radiating element of the proposed phased array antenna. By optimizing the spline function curve of the inner wall of the horn section, multi-mode electric field is excited in the horn aperture, therefore the radiating element can obtain higher aperture efficiency and more compact size. The phased array antenna is composed of 25 4 × 4 subarrays and the horn section of each subarray is fabricated by the 3d-printed technology. The simulated results indicate that the proposed phased array antenna has the bandwidth of 17.8-21.2 GHz with the voltage standing wave ratio (VSWR) below 1.35, and achieves ±8.7° beam scanning range in both E and H plane. The peak gain of the phased array antenna is 42.2 dBi at center frequency 19.2 GHz and the coverage gain of the phased array antenna are 40.9 dBi and 41.3 dBi in E and H plane at center frequency 19.2 GHz, respectively. © 2024 IEEE.

关键词： Horn antennas

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Application of X-band High Isolation Phased Array Payload in Satellite Data Transmission Communication

Application of X-band High Isolation Phased Array Payload in...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Liu, Zhenyang Zhang, Kuo Bao, Hongfei Song, Yang Science and Technology on Electronic Information Control Laboratory China

ISBN: (纸本)9798350375909

In this paper, a data transmission communication payload for low-orbit satellite constellation is designed and implemented, which is used for bidirectional data transmission between satellites and ground. The payload comprises a transmitting phased array and a receiving antenna module, the receiving antenna module comprises a wide-beam receiving antenna and a receiving front-end assembly, and the transmitting phased array integrates a transmitting antenna array, transmitting channel, frequency source, an up-and-down frequency conversion and a baseband processing module and a secondary power supply module. Each part of the transmission phased array adopts a modular design, and the signal is interconnected without cables through the motherboard and RF plug-in connectors, and the physical structure is compacts. Through the arrangement of transmitting and receiving antennas, filtering assistance, the effective filtering of the RF channel and the effective isolation of the frequency conversion channel realize the simultaneous operation of transmitting high EIRP and receiving high sensitivity in a wide angle range. At the same time, the payload also has a variety of capabilities such as simultaneous multi-user communication, on-orbit configurable key parameters, and on-orbit reconfigurable programs. © 2024 IEEE.

关键词： Antenna phased arrays

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Design of the Real-time control System for a Large-scaled Phased Array Based on High-speed Serial Bus

Design of the Real-time Control System for a Large-scaled Ph...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Wang, Wei Science and Technology on Electronic Information Control Laboratory China

ISBN: (数字)9798350375909

ISBN: (纸本)9798350375909

The realization of phase shift or delay of antenna array beam control based on FPGA. The accurate phase delay control of an active electronic scanning array (AESA) benefits from the implementation of the field programmable gate array (FPGA). Unfortunately, the complexity of phase delay control system increases as the scale of an AESA, and hence increasing the number of FPGAs that control the transmitting and receiving modules following each radiating element. This paper presents a system framework that combines the parallel processing capability of FPGA and high data transmission rate of low-voltage differential signaling (LVDS) bus protocol. The FPGA outputs the compressed data of the LVDS bus standard to the ASIC circuit, and the data is decoded into multi-bit low voltage transistor-transistor logic (LVTTL) data according to the corresponding decompression ratio by the destringer and phase-locked loop in the ASIC circuit. The data transmission rate can reach up to 360 Mbps. This proposed framework reduces the number of control lines to 22.2% compared to the traditional control method. © 2024 IEEE.

关键词： Phase locked loops

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Adjustable patch and feature prior token-based transformer for weakly supervised semantic segmentation

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International Journal of Computers and Applications 2024年第7期46卷 445-454页

作者： Li, Linjuan Zhang, Haoxue Xie, Gang Bai, Yanhong School of Electronic and Information Engineering Taiyuan University of Science and Technology Taiyuan China Shanxi Key Laboratory of Advanced Control and Equipment Intelligence Taiyuan China

Weakly supervised semantic segmentation is a challenging task, utilizing only low-cost weak supervision to produce pixel-level predictions. Existing transformer-based methods for weakly supervised semantic segmentation have some limitations: (1) Fixing patch size might destroy the structured semantics, which is unfriendly to objects of different scales, and (2) Ignoring the prior features when using multi-head attention mechanisms might lead to inaccurate segmentation localization. To tackle these issues, we proposed an effective transformer framework coupled with the adjustable patch and prior feature tokens, termed as APFPformer, in which an adjustable patch module is developed to split the image according to the area of the salient object for preserving the structured semantics in patches. A prior feature token module is devised to exploit the edge and texture information as prior tokens, ensuring the gain of discriminative representation. Additionally, a single-stage scheme is applied to reduce the computation and rapid segmentation process. Our experiments demonstrate the superiority of our approach over early methods, gaining competitive mean Intersection-over-Union scores of 67.9% on the PASCAL VOC2012 dataset and 40.2% on the MS COCO dataset. © 2024 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Semantic Segmentation

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An anonymous authentication and secure data transmission scheme for the Internet of Things based on blockchain

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Frontiers of Computer science 2024年第3期18卷 183-197页

作者： Xingxing CHEN Qingfeng CHENG Weidong YANG Xiangyang LUO State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China Henan Key Laboratory of Grain Photoelectric Detection and Control Henan University of TechnologyZhengzhou 450001China Henan Province Key Laboratory of Cyberspace Situation Awareness Zhengzhou Institute of Information Science and TechnologyZhengzhou 450001China

With the widespread use of network infrastructures such as 5G and low-power wide-area networks,a large number of the Internet of Things(IoT)device nodes are connected to the network,generating massive amounts of ***,it is a great challenge to achieve anonymous authentication of IoT nodes and secure data *** present,blockchain technology is widely used in authentication and s data storage due to its decentralization and ***,Fan et *** a secure and efficient blockchain-based IoT authentication and data sharing *** studied it as one of the state-of-the-art protocols and found that this scheme does not consider the resistance to ephemeral secret compromise attacks and the anonymity of IoT *** overcome these security flaws,this paper proposes an enhanced authentication and data transmission scheme,which is verified by formal security proofs and informal security ***,Scyther is applied to prove the security of the proposed ***,it is demonstrated that the proposed scheme achieves better performance in terms of communication and computational cost compared to other related schemes.

关键词： Internet of Things blockchain authentication data transmission

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A novel active-passive protection strategy endows carbonyl iron with excellent intelligent anti-corrosion and microwave absorption dual functional characteristics

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Nano Research 2025年第1期18卷 487-500页

作者： Wei Tian Quanyuan Feng Linbo Zhang Yinfan Liu Xian Jian Longjiang Deng Institute of Microelectronics School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 611756China National Engineering Researching Centre of Electromagnetic Radiation Control Materials Key Laboratory of Multi-Spectral Absorbing Materials and Structures of Ministry of EducationState Key Laboratory of Electronic Thin Films and Integrated DevicesSchool of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China The Yangtze Delta Region Institute(Huzhou)&School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaHuzhou 313001China

Carbonyl iron absorbers(CI)face significant challenges in practical applications,such as corrosion,interface bonding failure,detachment,and high maintenance ***,we have developed intelligent self-healing technology based on proactive/passive mechanisms via in situ synthesis of self-healing factors(polydopamine/benzotriazole(PDA/BTA))and physical barrier layers(SiO_(2)/1,1,1,3,3,3-hexamethyl disilazane,SiO_(2)/HMDS)to enhance corrosion resistance,while also being compatible with efficient microwave absorption *** unique multiscale structure gives full play to the utilization of the roles of each functional layer,including the intelligent self-healing features of PDA/BTA,physical shielding and spatial confinement characteristics of SiO_(2)/HMDS,and magnetic-dielectric synergistic mechanism resulted from the good impedance matching characteristics,the conduction loss,the interfacial polarization loss and natural *** asfabricated composites achieved an exceptional minimum reflection loss value of-55.4 dB at 10.7 GHz and the effective absorption band of 7.6 ***,it still exhibits obvious self-healing and corrosion resistance characteristics after 360 h corrosion treatment,ascribed to the self-healing mechanism of PDA/BTA and the blocking intervention effect of SiO_(2)/*** work is considered to pave the way for the synthesis of high-performance magnetic absorbers,especially in enhancing their intelligent self-healing ability in corrosive environments.

关键词： microwave absorption intelligent self-healing technology carbonyl iron multiscale structure magneticdielectric synergistic mechanism

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A Novel Asymmetric Check Microvalve for Suppressing Flow Boiling Instability in Microchannels

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Journal of Thermal science 2024年第6期33卷 2336-2347页

作者： ZHOU Fan ZHAO Yang YIN Ershuai HU Dinghua LI Qiang MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing 210094China

Flow boiling in microchannels has attracted wide attention due to its excellent heat transfer capability,but flow boiling instability is a huge challenge limiting its *** can lead to a series of problems,such as uneven flow distribution,temperature and pressure drop *** work proposes a novel asymmetric check microvalve(ACMV)structure,exhibiting high ratio of resistance between the reverse and forward *** results show the reverse pressure drop of the ACMV structure is 2.06 times that of the forward pressure drop,and the forward flow resistance of the ACMV structure is 16%smaller than that of the conventional inlet *** addition,bubble dynamics of an isolated bubble in the generated channel under dual outlet condition was numerically *** is found that the bubble grows symmetrically in the rectangular channel upstream and *** distance of bubble movement downstream in the microchannel with ACMV is three times that of the microchannel with inlet *** microchannel with ACMV can suppress the backflow of isolated bubble better than microchannel with inlet ***,the growth of the bubble downstream extends the effective evaporation domain,which contributes to the enhanced bubble growth *** ACMV is expected to be a potential replacement for the conventional inlet restrictor,which provides a novel and efficient solution for future heat dissipation from high power devices.

关键词： flow boiling instability topology optimization microchannel bubble dynamics

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Broad-Learning-System-Based Model-Free Adaptive Predictive control for Nonlinear MASs Under DoS Attacks

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 381-393页

作者： Hongxing Xiong Guangdeng Chen Hongru Ren Hongyi Li the School of Automation Guangdong-Hong Kong Joint Laboratory for Intelligent Decision and Cooperative Control Guangdong University of Technology Guangdong Provincial Key Laboratory for Intelligent Decision and Cooperative Control Guangdong University of Technology the College of Electronic and Information Engineering Southwest University IEEE

In this paper, the containment control problem in nonlinear multi-agent systems(NMASs) under denial-of-service(DoS) attacks is addressed. Firstly, a prediction model is obtained using the broad learning technique to train historical data generated by the system offline without DoS attacks. Secondly, the dynamic linearization method is used to obtain the equivalent linearization model of NMASs. Then, a novel model-free adaptive predictive control(MFAPC) framework based on historical and online data generated by the system is proposed, which combines the trained prediction model with the model-free adaptive control method. The development of the MFAPC method motivates a much simpler robust predictive control solution that is convenient to use in the case of DoS attacks. Meanwhile, the MFAPC algorithm provides a unified predictive framework for solving consensus tracking and containment control problems. The boundedness of the containment error can be proven by using the contraction mapping principle and the mathematical induction method. Finally, the proposed MFAPC is assessed through comparative experiments.

关键词： Broad learning technique denial-of-service (DoS) model-free adaptive predictive control (MFAPC) nonlinear multi-agent systems (NMASs)

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Dual control of amplitude and phase in a multilayer terahertz metasurface for transmission and reflection modulation

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Applied Optics 2025年第9期64卷 2276-2286页

作者： Zhang, Yuping Zheng, Siyu Hao, Xiaoyu Wang, Yu Liu, Yang Zhang, Min Liu, Meng Zhang, Huiyun Qingdao Key Laboratory of Terahertz Technology College of Electronic and Information Engineering Shandong University of Science and Technology Qingdao266590 China

Current metasurfaces encounter challenges in achieving precise control over transmittance-reflection mode conversion. This study presents a multilayer metasurface structure that incorporates dual amplitude and phase control, utilizing vanadium dioxide (VO2) and Dirac semimetals (DSMs) as tunable materials. By adjusting the orientation angle of the split-ring resonator (SRR) in the intermediate layer and modifying the Fermi energy level of the DSMs, precise dual control of amplitude and phase can be attained. When VO2 is in its insulating phase with a DSM Fermi level of 500 meV, the metasurface exhibits notable transmission characteristics, enabling refraction and focusing at 0.6 THz while demonstrating remarkable insensitivity to the incident angle. Conversely, when VO2 transitions to the metallic phase and the Fermi level of the DSMs is decreased to 1 meV, the metasurface displays significant reflection characteristics, facilitating the generation of vortex beam and multi-beam vortices. This multilayer metasurface holds considerable promise for applications in terahertz. © 2025 Optica Publishing Group. All rights, including for text and data mining (TDM), Artificial Intelligence (AI) training, and similar technologies, are reserved.

关键词： Vanadium dioxide

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