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Pattern Transformation of Low-Profile Multi-Mode Antenna for A Phased Array with Simultaneous Wide-Angle Scanning and High-Gain Properties

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IEEE Transactions on Antennas and Propagation 2025年

作者： Yan, Qi-Long Liu, Neng-Wu Zhu, Lei Yun, Yu Liu, Ying Xidian University National Key Laboratory of Radar Detection and Sensing Xi'an710071 China University of Macau Faculty of Science and Technology Department of Electrical and Computer Engineering China Shaanxi University of Science & Technology School of electronic information and artificial intelligence Xi'an710021 China

In this article, a novel multi-mode design approach for pattern transformation of low-profile multi-mode microstrip patch antenna (MPA) has been proposed and developed, aiming to simultaneously achieve the wide-angle scanning and high-gain properties for a phased array. Herein, the TM00, TM01, TM20, and TM21 modes of the MPA are employed. Firstly, the working principle about how to move these four modes closely to each other in resonant frequency is deeply studied, the results prove that the shorting pins and slots could be loaded on the radiator for frequency reallocation of these four modes. Secondly, the radiation pattern transformation of the MPA at TM00, TM20, and TM21 modes are deeply investigated, which demonstrates that the non-broadside beam of its TM21 mode could be reshaped into the broadside one, and the omnidirectional pattern of its TM00 mode could be reshaped into the dual beam at yoz-plane. Most importantly, the radiation pattern of its TM20 mode could be rotated into the dual-beam with co-polarized Eθ component at yoz-plane. With these arrangements, the broadside-beam and dual-beam could be excited under same frequency at different modes. Thirdly, based on these two beams with different phases at two ports, the antenna element has successfully gained the improved beam scanning and gain performance simultaneously. Fourthly, the proposed multi-mode array is arranged in a triangular grid. By controlling the phase difference between these ports, the antenna could achieve both wide-beam scanning and high gain. Experimental results show that the antenna element has an impedance bandwidth (|S11| © 1963-2012 IEEE.

关键词： Antenna phased arrays

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A Material Identification Approach Based on Wi-Fi Signal

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computers, Materials & Continua 2021年第12期69卷 3383-3397页

作者： Chao Li Fan Li Wei Du Lihua Yin Bin Wang Chonghua Wang Tianjie Luo Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510700China PCL Research Center of Cyberspace Security Peng Cheng LaboratoryShenzhen518052China Department of Computer Science and Computer Engineering University of ArkansasFayetteville72701USA College of Electrical Engineering Zhejiang UniversityHangzhou310058China China Industrial Control Systems Cyber Emergency Response Team Beijing100040China

Material identification is a technology that can help to identify the type of target *** approaches depend on expensive instruments,complicated pre-treatments and professional *** is difficult to find a substantial yet effective material identification method to meet the daily use *** this paper,we introduce a Wi-Fi-signal based material identification approach by measuring the amplitude ratio and phase difference as the key features in the material classifier,which can significantly reduce the cost and guarantee a high level *** practical measurement of WiFi based material identification,these two features are commonly interrupted by the software/hardware noise of the channel state information(CSI).To eliminate the inherent noise of CSI,we design a denoising method based on the antenna array of the commercial off-the-shelf(COTS)Wi-Fi *** that,the amplitude ratios and phase differences can be more stably utilized to classify the *** implement our system and evaluate its ability to identify materials in indoor *** result shows that our system can identify 10 commonly seen liquids with an average accuracy of 98.8%.It can also identify similar liquids with an overall accuracy higher than 95%,such as various concentrations of salt water.

关键词： Internet of Things Wi-Fi signal channel state information material identification noise elimination

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Secure Wireless-Powered zeRIS Communications

arXiv

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arXiv 2025年

作者： Chen, Jingyu Cao, Kunrui Diamantoulakis, Panagiotis D. Lv, Lu Yang, Liang Chi, Haolian Ding, Haiyang School of Information and Communications National University of Defense Technology Wuhan430035 China Department of Electrical and Computer Engineering Aristotle University of Thessaloniki Thessaloniki54124 Greece State Key Laboratory of Integrated Services Networks Xidian University Xi’an710071 China College of Computer Science and Electronic Engineering Hunan University Changsha410082 China

This paper introduces the concept of wireless-powered zero-energy reconfigurable intelligent surface (zeRIS), and investigates a wireless-powered zeRIS aided communication system in terms of security, reliability and energy efficiency. In particular, we propose three new wireless-powered zeRIS modes: 1) in mode-I, N reconfigurable reflecting elements are adjusted to the optimal phase shift design of information user to maximize the reliability of the system;2) in mode-II, N reconfigurable reflecting elements are adjusted to the optimal phase shift design of cooperative jamming user to maximize the security of the system;3) in mode-III, N1 and N2 (N1+N2 = N) reconfigurable reflecting elements are respectively adjusted to the optimal phase shift designs of information user and cooperative jamming user to balance the reliability and security of the system. Then, we propose three new metrics, i.e., joint outage probability (JOP), joint intercept probability (JIP), and secrecy energy efficiency (SEE), and analyze their closed-form expressions in three modes, respectively. The results show that under high transmission power, all the diversity gains of three modes are 1, and the JOPs of mode-I, mode-II and mode-III are improved by increasing the number of zeRIS elements, which are related to N2, N, and N12, respectively. In addition, mode-I achieves the best JOP, while mode-II achieves the best JIP among three modes. We exploit two security-reliability trade-off (SRT) metrics, i.e., JOP versus JIP, and normalized joint intercept and outage probability (JIOP), to reveal the SRT performance of the proposed three modes. It is obtained that mode-II outperforms the other two modes in the JOP versus JIP, while mode-III and mode-II achieve the best performance of normalized JIOP at low and high transmission power, respectively. © 2025, CC BY.

关键词： Outages

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Ultraviolet to Near-infrared Frequency Comb Generation in Lithium Niobate Nanophotonic Waveguides with Chirped Poling

Ultraviolet to Near-infrared Frequency Comb Generation in Li...

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CLEO: QELS_Fundamental Science, QELS 2022

作者： Wu, Tsung-Han Ledezma, Luis Fredrick, Connor Sekhar, Pooja Sekine, Ryoto Guo, Qiushi Briggs, Ryan Marandi, Alireza Diddams, Scott A. National Institute of Standards and Technology BoulderCO80305 United States Department of Physics University of Colorado BoulderCO80309 United States Department of Electrical Engineering California Institute of Technology PasadenaCA91125 United States Jet Propulsion Laboratory California Institute of Technology PasadenaCA91109 United States Electrical Computer and Energy Engineering University of Colorado BoulderCO80309 United States

We demonstrate thin-film lithium niobate waveguides with chirped poling periods for efficient supercontinuum via χ(2) and χ(3) nonlinearities. With picojoule energies, we generate gap free frequency combs spanning 3... 详细信息

ISBN: (纸本)9781557528209

关键词： Lithium

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UNDERSTANDING DOMAIN RANDOMIZATION FOR SIM-TO-REAL TRANSFER 10

UNDERSTANDING DOMAIN RANDOMIZATION FOR SIM-TO-REAL TRANSFER

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10th International Conference on Learning Representations, ICLR 2022

作者： Chen, Xiaoyu Hu, Jiachen Jin, Chi Li, Lihong Wang, Liwei Key Laboratory of Machine Perception MOE School of Artificial Intelligence Peking University China Department of Electrical and Computer Engineering Princeton University United States Amazon Key Laboratory of Machine Perception MOE School of Artificial Intelligence Peking University International Center for Machine Learning Research Peking University China

Reinforcement learning encounters many challenges when applied directly in the real world. Sim-to-real transfer is widely used to transfer the knowledge learned from simulation to the real world. Domain randomization-one of the most popular algorithms for sim-to-real transfer-has been demonstrated to be effective in various tasks in robotics and autonomous driving. Despite its empirical successes, theoretical understanding on why this simple algorithm works is limited. In this paper, we propose a theoretical framework for sim-to-real transfers, in which the simulator is modeled as a set of MDPs with tunable parameters (corresponding to unknown physical parameters such as friction). We provide sharp bounds on the sim-to-real gap-the difference between the value of policy returned by domain randomization and the value of an optimal policy for the real world. We prove that sim-to-real transfer can succeed under mild conditions without any real-world training samples. Our theory also highlights the importance of using memory (i.e., history-dependent policies) in domain randomization. Our proof is based on novel techniques that reduce the problem of bounding the sim-to-real gap to the problem of designing efficient learning algorithms for infinite-horizon MDPs, which we believe are of independent interest. © 2022 ICLR 2022 - 10th International Conference on Learning Representationss. All rights reserved.

关键词： Learning algorithms

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LanCOPE: Language-Guided Category-Level Object Pose Estimation from a Single RGB Image

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IEEE robotics and Automation Letters 2025年第7期10卷 7555-7562页

作者： Yang, Hui Sun, Wei Liu, Jian Zheng, Jin Dai, Zhenqi Mian, Ajmal Hunan University National Engineering Research Center for Robot Visual Perception and Control Technology College of Electrical and Information Engineering State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Changsha 410082 China Central South University School of Architecture and Art Changsha 410082 China The University of Western Australia Department of Computer Science and Software Engineering 6009 WA Australia

Monocular RGB-based category-level object pose estimation is more practical and cost-effective for robotics. However, existing methods do not fully exploit the rich semantic and contextual information in multimodal data (e.g. language) that provides additional object attributes to guide the model in extracting category features more reliably. We propose a language-guided category-level object pose estimation method (LanCOPE), taking a single RGB image as input. Our method uses DINOv2 to recover depth from a single RGB image and converts it into point cloud to perceive the object's geometry. We then introduce language descriptions for the RGB image, estimated point cloud and overall scene to better guide the point cloud encoder and image encoder in learning category features. We develop a cross-modal differential perception feature fusion network to fuse multimodal features. This network employs a differential perception module to eliminate redundant information across different modalities, highlighting signifcant semantic differences and similarities. Furthermore, it uses a cross-attention mechanism to fuse the semantic information of the language and vision features, improving the overall perception. Finally, we design a denoising network based on the skip fusion transformer to recover the object pose accurately. Extensive experiments on REAL275 and Wild6D datasets show that LanCOPE achieves state-of-the-art performance. Our code is available at LanCOPE. © 2016 IEEE.

关键词： category-level object pose estimation languag RGB image

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Multipactor Analysis of Dielectric-Loaded Parallel Plates with Local-Regional Increment of Secondary Emission Yield

Multipactor Analysis of Dielectric-Loaded Parallel Plates wi...

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International Conference on Vacuum Electronics

作者： Shu Lin Huan Zhong Lin Huang Yongdong Li Patrick Y. Wong Peng Zhang Key Laboratory for Physical Electronics and Devices of the Ministry of Education Xi'an Jiaotong University Xi'an China Air and Missile Defense College Air Force Engineering University Xi'an China Department of Electrical and Computer Engineering Michigan State University Michigan USA

ISBN: (数字)9798350348705

ISBN: (纸本)9798350348712

Multipactor effect is an undesired avalanche-like breakdown in powerful microwave devices, where the presence of dielectric material inevitably forms charge accumulation and accordingly leads to complicated dynamic evolution. Meanwhile, local-regional increment of secondary emission yield (SEY) is probably exacerbated by unexpected surface contamination or different surface roughness, especially for dielectric layers that are hard to polish at fabrication. In this research, the multipactor formation process in dielectric-loaded parallel plates with spatial SEY discrepancy on dielectric surface is investigated with 3D EM-PIC simulation. As revealed in the results, opposite charge polarity eventually forms in the high-SEY region on the dielectric surface, which fully dominates multipactor dynamic evolution as the region size increases.

关键词： Fabrication Three-dimensional displays Surface contamination Microwave devices Surface roughness Rough surfaces Dielectrics Vacuum electronics Electron sources Surface treatment

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Proposal and Synthesis Design of Multi-band Filtering Power Dividers 4

Proposal and Synthesis Design of Multi-band Filtering Power ...

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4th International Applied Computational Electromagnetics Society Symposium in China, ACES-China 2021

作者： Zhang, Gang Zhang, Zhuowei Li, Rui Zhu, Lei Jiangsu Key Laboratory of 3D Printing Equipment and Manufacturing School of Electrical and Automation Engineering Nanjing Normal University NNU Nanjing China University of Macau Faculty of Science and Technology Department of Electrical and Computer Engineering China

ISBN: (纸本)9781733509619

A direct synthesis design technique of multi-band filtering power dividers (FPDs) with high frequency selectivity is proposed, which is promising in both industrial and academic field. After a set of complete closed-form analytical equations are established for direct synthesis design, the proposed method is intensively described to reveal its powerful capacity in design of a multi-band FPD with any pre-specified responses, high multiband isolations and matching. To validate this design concept, a demonstrator triple-band microstrip FPD has been designed, fabricated, measured. What's more, a triple-band three-way FPD with 90° port-to-port phase differences as an extended example of the synthesis design technique has also been implemented, which furtherly shows the flexibility of the proposed method. © 2021 Applied Computational Electromagnetics Society (ACES).

关键词： Design

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Strain-enhanced dynamic regulation of chiroptical responses in 3D suspended nested metamaterials

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Optics Express 2025年第11期33卷 23440-23451页

作者： Li, Bo Duan, Shilong Zou, Qiushun Guo, Ruansheng Chen, Yimin Gu, Chenjie Zhang, Peiqing Shen, Xiang Faculty of Electrical Engineering and Computer Science Ningbo University Ningbo315211 China Laboratory of Infrared Material and Devices Zhejiang Key Laboratory of Advanced Optical Functional Materials and Devices Advanced Technology Research Institute Ningbo University Zhejiang 315211 China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern Mechanics University of Science and Technology of China Anhui Hefei230027 China

Three-dimensional (3D) chiral metamaterials, which exhibit strong chiroptical responses, have attracted tremendous attention in the broad fields of next-generation photonic devices and chiroptical spectroscopy techniques. There is an urgent need for a novel fabrication approach that enables the rapid and straightforward preparation of 3D chiral nanostructures, along with a robust strategy for achieving dynamic regulation. Here, we proposed a strain-enhanced strategy for dynamically regulating the chiroptical responses of 3D suspended nested metamaterials from the transformation of a 2D precursor. The local strain enhancement could effectively resolve the bottleneck of insufficient strain and low precision for the buckling strain self-assembly. The changing morphology and circular dichroism (CD) of 3D suspended chiral metamaterials were analyzed under the impact of a strain-enhanced effect. Then, the uplifted heights of these 3D nanostructures increased with the substrate’s pre-strain (Εpre). Its CD reached up to 0.79, mainly resulting from ring electric dipoles. Interestingly, the chiroptical responses of 3D nanopyramids were regulated dynamically by controlling the substrate’s pre-strain. Such a strategy provides a new pathway for achieving high-performance chiral metamaterials and offers promising applications in circularly polarized light detection, super-chiral light sources, optical communication, and advanced nanophotonic systems. © 2025 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement.

关键词： Metamaterials

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Impacts of Heavy Particle Irradiation on Very High Frequency Microelectromechanical Resonators

Impacts of Heavy Particle Irradiation on Very High Frequency...

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IEEE Symposium (IUS) Ultrasonics

作者： David D. Lynes Joshua Young Eric Lang Hengky Chandrahalim Department Electrical and Computer Engineering Air Force Institute of Technology Wright-Patterson Air Force Base OH USA Ion Beam Laboratory Sandia National Laboratories Albuquerque NM USA Department of Nuclear Engineering The University of New Mexico Albuquerque NM USA Department of Electrical and Computer Engineering Air Force Institute of Technology Wright-Patterson Air Force Base OH USA

This study explores the interrelationship between silicon ion irradiation and piezoelectrically-actuated microelectromechanical systems (MEMS) resonators. Specifically, it assesses the effect of incorporating a thin silicon oxide (SiO 2 ) dielectric layer into the resonator structure. The MEMS resonators engineered for this investigation include Aluminum Nitride on Silicon (AlN-on-Si) and AlN-SiO 2 -Si width extensional mode (WEM) types. These devices underwent irradiation with 2 MeV Si + ions at a total fluence of 5 x 10 14 ions cm -2 . On-site S-parameter measurements were conducted. The research quantitatively outlines radiation-induced damage coefficients, elucidating their influence on key performance metrics such as resonant frequency (f r ), quality factor (Q), motional resistance (R m ), and electromechanical coupling factor ($\left({{k_{eff}}^2}\right)$.

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