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Cooperative interactions between nano-antennas in a high-Q cavity for unidirectional light sources

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Light(Science & Applications) 2019年第1期8卷 82-95页

作者： Kevin G.Cognee Hugo M.Doeleman Philippe Lalanne A.F.Koenderink Center for Nanophotonics AMOLFScience Park 1041098 XG AmsterdamThe Netherlands LP2N Institut d’Optique Graduate SchoolCNRSUniversity of Bordeaux33400 TalenceFrance Van der Waals-Zeeman Institute University of AmsterdamScience Park 9041090 GL AmsterdamThe Netherlands

We analyse the resonant mode structure and local density of states in high-Q hybrid plasmonic-photonic resonators composed of dielectric microdisks hybridized with pairs of plasmon antennas that are systematically swept in position through the cavity mode.On the one hand,this system is a classical realization of the cooperative resonant dipole–dipole interaction through a cavity mode,as is evident through predicted and measured resonance linewidths and shifts.At the same time,our work introduces the notion of‘phased array’antenna physics into plasmonic-photonic resonators.We predict that one may construct large local density of states(LDOS)enhancements exceeding those given by a single antenna,which are‘chiral’in the sense of correlating with the unidirectional injection of fluorescence into the cavity.We report an experiment probing the resonances of silicon nitride microdisks decorated with aluminium antenna dimers.Measurements directly confirm the predicted cooperative effects of the coupled dipole antennas as a function of the antenna spacing on the hybrid mode quality factors and resonance conditions.

关键词： antenna antennas cavity

Co-aperture arrangement of dual antennas for orientation and telemetry in a conformal cavity

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1133-1138页

作者： Zong Xianzheng Nie Zaiping Wang Jun School of Electronic Engineering Univ. of Electronic Science and Technology Chengdu 610054 P. R. China Inst. of Electronic Engineering Chinese Academy of Engineering Physics Mianyang 621900 P. R. China

The feasibility of making two antennas work within a shared aperture conformai to a platform like an aircraft or a missile is investigated. The shared aperture is enclosed by a deep cavity, which is covered by a columniform dielectric radome. A modified quadrifilar helix antenna （QHA） with extended volute arms and a vertical monopole with a ring shaped ground are arranged in this co-aperture for global position system （GPS） orientation and telemetry, respectively. The effects of the cavity on these two antennas and the mutual coupling between these two antennas are studied through large numbers of experiments. The results show that the QHA has a strong influence on the monopole; however, these two antennas of the overall arrangement can perform simultaneously well within the aperture. The QHA has a right hand circular polarization （RHCP） and a broad beam normal to the radome topside, meanwhile the monopole can be used to produce a main lobe in the grazing direction above the aperture in some certain cases of the vertical location of the QHA in the cavity.

关键词： antennas co-aperture cavity radome

HB-Protocol Based Advance Security System for PKES Using Multiple antennas

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China Communications 2018年第12期15卷 98-110页

作者： Ahmer Khan Jadoon Licheng Wang Muhammad Azam Zia State key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Department of Computer Science University of Agriculture Faisalabad

Modern cars are mostly computerized and equipped with passive keyless entry and start(PKES) system. PKES is based on Radio Frequency Identification(RFID) technology for authentication of the authorized drivers. RFID technology has replaced the conventional ways of identification and authorization in order to facilitate users while introducing new security challenges. In this article, we focused on verifying the presence of authorized key in the physical proximity of car by employing multiple antennas. Application of multiple antennas to the currently developed cryptographic algorithms opens a new approach for researchers to improve security of RFID based systems. We propose an advanced security system for PKES using multiple antennas wherein an authorized key passes through multiple vicinities to allow driver to access and start the car. Furthermore, we modified a light-weight cryptographic protocol named as HB(Hopper and Blum) protocol to integrate it with the proposed design based on multiple antennas. Simulation results show improvement in security functionality while keeping in view the efficiency constraints.

关键词： passive keyless entry and start radio frequency identification hopper and blum protocol multiple antennas authorization

A new technique for separation of partial discharge sources and electromagnetic noise in radiofrequency measurements using energy ratios of different antennas

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High Voltage 2021年第3期6卷 525-530页

作者： Jorge A.Ardila‐Rey Matias Cerda‐Luna Rodrigo Rozas‐Valderrama Bruno Albuquerque de Castro AndréLuiz Andreoli Benjamin Cevallos Departamento de Ingeniería Eléctrica Universidad Técnica Federico Santa MaríaSantiago de ChileChile Department of Electrical Engineering São Paulo State University(UNESP)School of Engineering BauruBauru‐SPBrazil

One of the main tools for monitoring the condition of high voltage equipment is the measurement of partial discharges(PD).The electromagnetic(EM)radiation originated from this degradation phenomenon can be captured by various types of ultra‐high fre-quency(UHF)antennas carefully designed and optimised for specific frequency bands.However,the presence of environmental noise may limit the use of this technique.Different types of monopole antennas normally used in UHF PD measurement have been evaluated in order to validate the performance of a novel separation technique of EM sources.Accordingly,a new separation technique based on the energy ratio of the captured signals was developed,considering noise interferences.The results revealed that the new technique allows an adequate separation,even when three sources act simultaneously.

关键词： antennas separation noise

Multimode Resonator Technique in antennas:A

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Electromagnetic Science 2023年第1期1卷 89-105页

作者： Lei Zhu Nengwu Liu University of Macao Macao 999078China Xidian University Xi’an 710071China

During the past several decades,the multimode resonator(MMR)technique has been extensively investigated and widely used,with successful exploration of a variety of high-performance patch antennas,slot antennas,dielectric resonant antennas,dipole antennas,and so on.In this review paper,we summarize the research milestones for these MMR antennas worldwide as one of the most contributive research teams in this field.First,the basic working principles of the MMR technique are clearly illustrated and studied,including mode excitation,mode suppression,impedance performance improvement,and radiation performance improvement.Next,the research topics regarding impedance performance enhancement,i.e.,widebandwidth operation,multibandwidth operation,and mutual coupling reduction,based on the MMR method are intensively described.After that,the relevant works on radiation performance enhancement,i.e.,high-gain,wide-beamwidth,multibeam,multipolarization,low-cross-polarization,filtering-response,and leaky-wave antennas,based on the MMR method are extensively illustrated.By using this technique,several ideas about operating frequency reallocation,electric-field null control,radiation pattern reshaping,and efficiency null generation of the antennas are proposed and demonstrated by our team for the first time.In addition,the application of the MMR technique for wireless communication systems is introduced and presented,such as implant communication,wireless power transfer,and multiple-input multiple-output communication.With these arrangements,exploration and reporting of more interesting and useful MMR design methods can be anticipated in the future.

关键词： antennas Multimode resonator Impedance performance Radiation performance

THE MOMENT METHOD ON RESONANT QUADRIFILAR HELICAL antennas

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Journal of Electronics(China) 1990年第1期7卷 30-36页

作者：易力 Institute of Spacecraft System Engineering The Chinese Academy of Space TechnologyBeijing

An efficient measure is taken to rearrange Nakano’s kernels of integral equationsfor an antenna system composed of arbitrarily bent wires.By means of the moment method,great efforts are made to analyze and compute the circularly polarized patterns,directivity,axialratio,front-to-back ratio and beam-shaping characteristics of resonant quadrifilar helical antennasas well as the feeding technique and the effect of an electrically large conducting body on theperformance of the antennas.

关键词： Helical antennas Kernels of integral equations Moment method

DIRECTIVITY OPTIMIZATION OF CURVED SURFACE DIPOLE antennas

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Journal of Electronics(China) 1994年第4期11卷 322-331页

作者：王均宏任朗 Institute of EM Theory and Microwave Tech. Southwest Jiaotong University Chengdu 610031

Based on the calculation of the characteristic parameters by moment method, the curved surface dipoles are optimized by an optimization method, the maximum directivities of some V-curved and Gauss-curved surface dipol... 详细信息

关键词： antennas Curved surface dipoles Directivity Optimization Moment method

Quasi-omnibearing retro-reflective metagrating protected by reciprocity

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Photonics Research 2022年第4期10卷 843-854页

作者： Yuxiang Jia Jiafu Wang Yajuan Han Ruichao Zhu Zhongtao Zhang Jie Yang Yueyu Meng Yongfeng Li Shaobo Qu Department of Basic Sciences Air Force Engineering UniversityXi’an 710051China Shaanxi Key Laboratory of Artificially-Structured Functional Materials and Devices Xi'an 710051China

Reciprocity is ubiquitous in antennas for receiving and radiating electromagnetic(EM) waves, i.e., if an antenna has good receiving performance at a given direction, it also has good radiation performance in that direction.Inspired by this, we propose a method of designing a quasi-ominibearing retro-reflective metagrating(RRMG)protected by the reciprocity of antennas. Based on the second-order mode around 15.0 GHz of a short-circuited structured patch antenna(SPA), incident transverse magnetic waves can be received, channeled into the coaxial lines, reflected by the shortened end, and finally re-radiated into free space with a reversed wave vector. RRMGs are contrived consisting of this identical SPA, with a grating constant allowing ±2nd-, ±1st-, and zeroth-order diffractions. Oblique incidence, plus the tilted nulls of the re-radiation pattern, can eliminate -1st, zeroth,+1st, and +2nd orders, and only the -2nd order is left to achieve retro-reflections. Prototypes were fabricated and measured. Simulated and measured results show that the RRMGs maintain only -2nd-order diffraction for incident angles 32.2° ≤ θ_(i)< 90.0° in four quadrants, and that RRMGs can achieve quasi-omnibearing retro-reflections for θ_(i)= 50.0°. The use of higher-order diffraction brings more degrees of freedom in manipulating EM waves, and this strategy can be readily extended to millimeter waves, THz wave, or even optical regimes.

关键词： reflective antenna antennas

Beamforming Performance Analysis of Millimeter-Wave 5G Wireless Networks

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Computers, Materials & Continua 2022年第3期70卷 5383-5397页

作者： Omar A.Saraereh Ashraf Ali Deparment of Electrical Engineering Engineering FacultyThe Hashemite UniversityZarqa13133Jordan

With the rapid growth in the number of mobile devices and user connectivity,the demand for higher system capacity and improved qualityof-service is required.As the demand for high-speed wireless communication grows,numerous modulation techniques in the frequency,temporal,and spatial domains,such as orthogonal frequency division multiplexing(OFDM),time division multiple access(TDMA),space division multiple access(SDMA),and multiple-input multiple-output(MIMO),are being developed.Along with those approaches,electromagnetic waves’orbital angular momentum(OAM)is attracting attention because it has the potential to boost the wireless communication capacity.Antenna electromagnetic radiation can be described by a sum of Eigen functions with unique eigenvalues,as is well known.In order to address such issues,the millimeter-wave(mmWave)communication is proposed which is considered as one of the potential technology for 5G wireless networks.The intrinsic feature of all electromagnetic waves is OAM.The OAM beams’unique qualities have led to a slew of new uses.Broadband OAM generators,on the other hand,have gotten very little attention,especially in the mmWave frequency band.The use of OAM in conjunction with mmWave can reduce the beam power loss,enhance the received signal quality,and hence increase the systemcapacity.The transmitter and receiver antennas must be coaxial and parallel to achieve precise mode detection.The proposed mmWave integrated with OAM system model is discussed in this study.The channel model is created using the channel transition characteristics.The simulation results demonstrate that the proposed system model is a good way to boost the system capacity.

关键词： antennas beamforming radiation pattern mmwave optimization