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Accurate and broadband manipulations of harmonic amplitudes and phases to reach 256 QAM millimeter-wave wireless communications by time-domain digital coding Metasurface

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National Science Review 2022年第1期9卷 36-46页

作者： Ming Zheng Chen Wankai Tang Jun Yan Dai Jun Chen Ke Lei Zhang Cheng Zhang Jin Yang Lianlin Li Qiang Cheng Shi Jin Tie Jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Terahertz and Millimeter Waves City University of Hong Kong State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronics Peking University National Mobile Communications Research Laboratory Southeast University State Key Laboratory of Millimeter Waves Southeast University Center of Intelligent Metamaterials Pazhou Laboratory

We propose a theoretical mechanism and new coding strategy to realize extremely accurate manipulations of nonlinear electromagnetic harmonics in ultrawide frequency band based on a time-domain digital coding Metasurface(TDCM).Using the proposed mechanism and coding strategy,we design and fabricate a millimeter-wave(mmWave) TDCM,which is composed of reprogrammable meta-atoms embedded with positive-intrinsic-negative diodes.By controlling the duty ratios and time delays of the digital coding sequences loaded on a TDCM,experimental results show that both amplitudes and phases of different harmonics can be engineered at will simultaneously and precisely in broad frequency band from 22 to33 GHz,even when the coding states are imperfect,which is in good agreement with theoretical calculations.Based on the fabricated high-performance TDCM,we further propose and experimentally realize a large-capacity mmWave wireless communication system,where 256 quadrature amplitude modulation,along with other schemes,is demonstrated.The new wireless communication system has a much simpler architecture than the currently used mmWave wireless systems,and hence can significantly reduce the hardware cost.We believe that the proposed method and system architecture can find vast application in future mmWave and terahertz-wave wireless communication and radar systems.

关键词： Metasurface time-domain digital coding accurate and broadband harmonic control 256 QAM millimeter-wave wireless communications

Transformation of a Metasurface on the substrate interface into the same Metasurface in a homogenized substrate based on two kinds of modified Babinet's principles

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Science China(Information Sciences) 2023年第12期66卷 238-250页

作者： Xiaobo LIU Rui LU Anxue ZHANG Qiang CHENG Xiaoming CHEN School of Information and Communications Engineering Xi'an Jiaotong University School of Mathematics and Statistics Xi'an Jiaotong University State Key Laboratory of Millimeter Waves and School of Electrical Engineering Southeast University

Previously, the Metasurface was usually manufactured on a dielectric substrate using the printed circuit boards(PCB) technology. However, due to the existence of the substrate interface, the electromagnetic radiation and coupling of the sub-wavelength Metasurface becomes more complex for theoretical analysis. To this end, an indirect method is developed to transform the problem of a Metasurface in a dielectric half-space into a simpler problem of the same Metasurface in a homogenized dielectric space. Specifically, two different theoretical models of complementary Metasurfaces in a dielectric half-space are first given. A specific yet unknown relative permittivity is included in one model to realize the above transformation. By comparing these two theoretical models in terms of the surface impedance matrix, the specific yet unknown relative permittivity is analytically derived as (εr,unk)1/2=(εr,1)1/2/2 +(εr,2)1/2/2. Finally, two arbitrary Metasurfaces are given to verify the proposed theory for arbitrary incidence wave in dielectric half-space. The theory can greatly simplify the analysis and design of the Metasurface in a dielectric halfspace, because only the Metasurface in a homogenized dielectric space like vacuum needs to be theoretically solved after completing the above transformation.

关键词： dielectric half-space homogenized dielectric space Metasurface relative permittivity surface impedance matrix substrate interface

An ultra-sensitive Metasurface biosensor for instant cancer detection based on terahertz spectra

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Nano Research 2023年第5期16卷 7304-7311页

作者： Peiliang Wang Jing Lou Yun Yu Lang Sun Lan Sun Guangyou Fang Chao Chang Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Innovation Laboratory of Terahertz Biophysics National Innovation Institute of Defense TechnologyBeijing 100071China The Key Laboratory of Electromagnetic Radiation and Sensing Technology Chinese Academy of SciencesBeijing 100190China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Institute of Acupuncture and Moxibustion China Academy of Chinese Medical SciencesBeijing 100007China School of Psychological and Cognitive Sciences Beijing Key Laboratory of Behavior and Mental HealthPeking UniversityBeijing 100871China School of Life Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

Metasurface biosensors have become the core label-free and rapid-detection technology in bioanalysis.Lung cancer and brain cancer are the first leading causes of cancer death among adults and adolescents,respectively,where poor early diagnosis results from expensive detection costs and time consumption.To tackle the above problems,here,we introduce a terahertzdomain Metasurface biosensor for cancer diagnosis,relying on a perfectly symmetrical periodic surface structure,which significantly exhibits polarization-insensitivity at 2.05 THz and the high-sensitivity of 504 GHz/RIU(RIU=refractive index unit).According to the frequency shifts and transmittance variations,four cell types are successfully distinguished from each other.The minimum number of cells is required for thousands of cells to display the differences of spectra,which is 1/30 of clinical methods.Furthermore,the results were consistent with pathological results(the gold standard in clinic)by Gaussian curve fitting.The proposed biosensor has really achieved the characterization of cells in normal and cancerous state.This detection strategy dramatically reduced the cost of detection by reuse and time consumption was reduced to 1/20 of the pathology testing.In addition,it is flexible to set samples and easy to realize automatic operation due to the great polarization-insensitivity of the proposed biosensor,which can further reduce labor costs in the future.It is envisioned that the proposed biosensor will present immense potential in the fields of cancer detection,distinguishing different cancers,identifying primary lesion cancer or metastatic cancer.

关键词： terahertz Metasurface biosensor cancer detection

5G Antenna Gain Enhancement Using a Novel Metasurface

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Computers, Materials & Continua 2022年第8期72卷 3601-3611页

作者： Mubashir Ashfaq Shahid Bashir Syed Imran Hussain Shah Nisar Ahmad Abbasi Hatem Rmili Muhammad Abbas Khan Department of Electrical Engineering UETPeshawar25000Pakistan Department of Electrical Engineering Chungnam National UniversityDaejeonKorea Department of Electrical Engineering University of Hafr Al BatinKSA Electrical and Computer Engineering Department Faculty of EngineeringKing Abdulaziz UniversityJeddahKSA K.A.CARE Energy Research and Innovation Center King Abdulaziz UniversityJeddah21589KSA Department of Electrical Engineering Balochistan University of Information TechnologyEngineering and Management SciencesQuettaPakistan

This article presents a Sub-6 GHz microstrip patch antenna(MPA)with enhanced gain using metamaterial(MTM)superstrate.The source MPA operates at 4.8 GHz and has a peak gain of 5.3 dBi at the resonance frequency.A window-shaped unit cell is designed and investigated through the material wave propagation technique.The unit cell shows an EpsilonNear Zero(ENZ)-Mu Very Large(MVL)behavior around 4.8 GHz.The unit cell has a fourfold geometry which makes it a polarization independent metamaterial.A double layer antenna is designed by placing a 4×4 MTM slab as a superstrate above the MPA at a height of 0.208λ0;whereλ0 is the free-space wavelength at the resonance frequency of the antenna.Impedance matching and gain of the source antenna is improved using the metamaterial.The simulation as well as measurement results show that novel antenna system has a peak gain of 7.68 dBi at 4.8 GHz and an impedance bandwidth of 0.22 GHz.The overall dimension of the antenna is 75×60×15 mm^(3).The proposed antenna operates in the Sub-6 GHz band and is suitable for 5G applications.

关键词： Metasurface 5G gain directivity polarization

Anisotropic and nonlinear Metasurface for multiple functions

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Science China(Information Sciences) 2021年第9期64卷 165-174页

作者： Zhangjie LUO Xueyao REN Qiang WANG Qiang CHENG Tiejun CUI State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast University Pazhou Lab Air and Missile Defense College Air Force Engineering University

We present a novel anisotropic and nonlinear Metasurface integrated with multiple functions of diffuse scattering, beam splitting, and normal reflection, which can be switched in real time by tuning the polarization state or power level of the incident microwave. The key lies in the two judiciously designed anisotropic nonlinear particles in subwavelength scales that possess opposite reflection phases under one polarization and the same nonlinear power-dependent reflection phases under the orthogonal polarization. These properties are demonstrated comprehensively via comparisons between their reflection responses, receiving abilities, and nonlinear circuitry behaviors. In addition, both the spatial arrangement and the electrically enabling strategy of the particles are underpinned to pursue the proposed functions, which are verified through numerical simulations and measurements. When the Metasurface is illuminated by plane waves coming from the direction perpendicular to it, a significant beam splitting effect is achieved with strong x-polarized incidence,which is switched to a specular reflection when the incoming power decreases. Under y-polarization,a diffuse scattering phenomenon is obtained, which is not dependent on the incident intensity. The study is expected to offer new solutions to many electromagnetic scenarios involving energy transmissions and protections.

关键词： multi-function Metasurface nonlinear anisotropic polarization

Programmable time-domain digital-coding Metasurface for non-linear harmonic manipulation and new wireless communication systems

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National Science Review 2019年第2期6卷 231-238页

作者： Jie Zhao Xi Yang Jun Yan Dai Qiang Cheng Xiang Li Ning Hua Qi Jun Chen Ke Guo Dong Bai Shuo Liu Shi Jin Andrea Alù Tie Jun Cui State Key Laboratory of Millimeter Waves Southeast University Jiangsu Cyber-Space Science & Technology Co. Ltd Physics Program The Graduate Center City University of New York National Mobile Communication Research Laboratory Southeast University Synergetic Innovation Center of Wireless Communication Technology Southeast University Department of Electrical Engineering City College of New York Photonics Initiative Advanced Science Research Center City University of New York

Optical non-linear phenomena are typically observed in natural materials interacting with light at high intensities, and they benefit a diverse range of applications from communication to sensing. However,controlling harmonic conversion with high efficiency and flexibility remains a major issue in modern optical and radio-frequency systems. Here, we introduce a dynamic time-domain digital-coding Metasurface that enables efficient manipulation of spectral harmonic distribution. By dynamically modulating the local phase of the surface reflectivity, we achieve accurate control of different harmonics in a highly programmable and dynamic fashion, enabling unusual responses, such as velocity illusion. As a relevant application, we propose and realize a novel architecture for wireless communication systems based on the time-domain digital-coding Metasurface, which largely simplifies the architecture of modern communication systems, at the same time yielding excellent performance for real-time signal transmission. The presented work, from new concept to new system, opens new pathways in the application of metamaterials to practical technology.

关键词： Metasurface time-domain digital coding non-linear harmonics control new architecture of communication

Optimization design of autofocusing Metasurface for ultrasound wave application

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Journal of Advanced Dielectrics 2024年第1期14卷 51-58页

作者： Zhaoxi Li Shenghui Yang Mengqing Zhou Chenxue Hou Dongdong Chen Chunlong Fei Di Li Yi Quan Yintang Yang School of Microelectronics Xidian UniversityXi’anShaanxi 710071P.R.China

In this paper,two optimized autofocusing Metasurfaces(AFMs)with different desired focal distances are designed by using particle swarm optimization(PSO)algorithm.Based on the ffnite element simulation software COMSOL Multiphysics,the performance of ultrasound transducer(UT)with AFM at different design parameters in Airy distributions(r0,ω)and the bottom thickness(d)of AFM are simulated and analyzed.Based on the simulation data,the artiffcial neural network model is trained to describe the complex relationship between the design parameters of AFM and the performance parameters of UT.Then,the multiobjective optimization function for AFM is determined according to the desired performance parameters of UT,including focal position,lateral resolution,longitudinal resolution and absolute sound pressure.In order to obtain AFMs with the desired performance,PSO algorithm is adopted to optimize the design parameters of AFM according to the multiobjective optimization function,and two AFMs are optimized and fabricated.The experimental results well agree with the simulation and optimization results,and the optimized AFMs can achieve the desired performance.The fabricated AFM can be easily integrated with UT,which has great potential applications in wave ffeld modulation underwater,acoustic tweezers,biomedical imaging,industrial nondestructive testing and neural regulation.

关键词： Autofocusing Metasurface ultrasound transducer optimization

Narrowband perfect terahertz absorber based on polar-dielectrics Metasurface

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Chinese Physics B 2020年第5期29卷 297-302页

作者：赵萌萌付淑芳周胜宋玉玲张强尹永琦) 赵玉田梁红王选章 Key Laboratory for Photonic and Electronic Bandgap Materials(Ministry of Education) School of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China Department of Electrical Engineering University of CaliforniaRiversideCalifornia 92521USA School of Technology Harbin Normal UniversityHarbin 150086China

We theoretically propose a narrowband perfect absorber Metasurface(PAMS) based on surface phonon polaritons in the terahertz range. The PAMS has unit cell consisting of a silver biarc on the top, a thin polar-dielectric in the middle and a silver layer at the bottom. The phonon polaritons are excited at the interface between the silver biarc and the polar dielectric, and enhance the absorption of the PAMS. The absorption peak is at 36.813 μm and the full width half maximum(FWHM) is nearly 36 nm, independent of the polarization and incidence angle. The electric fields are located at the split of the biarc silver layer and the quality factor Q is 1150. The FWHM decreases with the decreasing split width. When the thickness of the bottom layer is larger than 50 nm, the narrow band and high absorption are insensitive to the thickness of those layers. The designed absorber may have useful applications in terahertz spectra such as energy harvesting, thermal emitter, and sensing.

关键词： Metasurface narrowband perfect absorber terahertz polar-dielectrics

维普期刊数据库

Single-Layer Wideband Circularly Polarized Antenna Using Non-Uniform Metasurface for C-band Applications

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Computers, Materials & Continua 2021年第8期68卷 2487-2498页

作者： Huy Hung Tran Khoa Nguyen-Dang Niamat Hussain Faculty of Electrical and Electronic Engineering PHENIKAA UniversityHanoi12116Vietnam PHENIKAA Research and Technology Institute(PRATI) A&A Green Phoenix Group JSCCau Giay11313HanoiVietnam Department of Computer and Communication Engineering Chungbuk National UniversityCheongju 28644Korea

A single-layer design of non-uniform Metasurface(MS)based circularly polarized(CP)antenna with wideband operation characteristic is proposed and investigated in this paper.The antenna is excited by a truncated corner squared patch as a primary radiating CP source.Then,a non-uniform MS is placed in the same layer with the driven patch.Besides increasing the impedance bandwidth,the non-uniform MS also generates two additional CP bands in the high frequency band,leading to significantly increase the antenna’s overall performances.The use of non-uniform MS distinguishes our design from the other CP MS based antennas in literature,in which the MS is formed by multiple uniform unit cells and placed in different layer with the radiating element.For validation,an antenna prototype,whose overall dimensions of 0.94λ_(o)×0.94λ_(o)×0.06λ_(o) at the center operating frequency,is fabricated and experimentally tested.The measured operating bandwidth with|S11|≤−10 dB and AR≤3 dB is 27.1%(5.1–6.7 GHz)and the broadside gain within this band is from 5.7 to 7.2 dBic.Compared to the other related works,the proposed antenna has advantage of very wideband operation with single-layer design.

关键词： Circular polarization Metasurface non-uniform patch antenna wideband