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An externally perceivable smart leaky-wave antenna based on spoof surface plasmon polaritons
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作者 Weihan Li Jia Chen +6 位作者 Shizhao Gao Lingyun Niu Jiaxuan Wei Ruosong Sun Yaqi Wei Wenxuan Tang Tie Jun Cui 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第9期5-20,共16页
Smart antennas have received great attention for their potentials to enable communication and perception functions at the same time.However,realizing the function synthesis remains an open challenge,and most existing ... Smart antennas have received great attention for their potentials to enable communication and perception functions at the same time.However,realizing the function synthesis remains an open challenge,and most existing system solutions are limited to narrow operating bands and high complexity and cost.Here,we propose an externally perceivable leakywave antenna(LWA)based on spoof surface plasmon polaritons(SSPPs),which can realize adaptive real-time switching between the“radiating”and“non-radiating”states and beam tracking at different frequencies.With the assistance of computer vision,the smart SSPP-LWA is able to detect the external target user or jammer,and intelligently track the target by self-adjusting the operating frequency.The proposed scheme helps to reduce the power consumption through dynamically controlling the radiating state of the antenna,and improve spectrum utilization and avoid spectrum conflicts through intelligently deciding the radiating frequency.On the other hand,it is also helpful for the physical layer communication security through switching the antenna working state according to the presence of the target and target beam tracking in real time.In addition,the proposed smart antenna can be generalized to other metamaterial systems and could be a candidate for synaesthesia integration in future smart antenna systems. 展开更多
关键词 smart antenna external perception spoof surface plasmon polaritons computer vision aids
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Radio Propagation and Wireless Coverage of LSAA-Based 5G Millimeter-Wave Mobile Communication Systems 被引量:12
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作者 Haiming Wang Peize Zhang +1 位作者 Jing Li Xiaohu You 《China Communications》 SCIE CSCD 2019年第5期1-18,共18页
Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell ra... Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell radii and complicated network architectures. A coverage extension scheme using large-scale antenna arrays(LSAAs) has been suggested and theoretically proven to be cost-efficient in combination with ultradense small cell networks. To analyze and optimize the LSAA-based network deployments, a comprehensive survey of recent advances in statistical mmWave channel modeling is first presented in terms of channel parameter estimation, large-scale path loss models, and small-scale cluster models. Next, the measurement and modeling results at two 5G candidate mmWave bands(e.g., 28 GHz and 39 GHz) are reviewed and compared in several outdoor scenarios of interest, where the propagation characteristics make crucial contributions to wireless network designs. Finally, the coverage behaviors of systems employing a large number of antenna arrays are discussed, as well as some implications on future mmWave cellular network designs. 展开更多
关键词 FIFTH generation (5G) channel modeling large-scale antenna array(LSAA) MILLIMETER wave(mmWave) COMMUNICATIONS RADIO propagation measurements wireless COVERAGE
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Joint Modulations of Electromagnetic Waves and Digital Signals on a Single Metasurface Platform to Reach Programmable Wireless Communications 被引量:2
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作者 Xiang Wan Chaokun Xiao +10 位作者 He Huang Qiang Xiao Wei Xu Yueheng Li Joerg Eisenbeis Jiawei Wang Ziai Huang Qiang Cheng Shi Jin Thomas Zwick Tiejun Cui 《Engineering》 SCIE EI 2022年第1期86-95,共10页
In current wireless communication and electronic systems,digital signals and electromagnetic(EM)radiation are processed by different modules.Here,we propose a mechanism to fuse the modulation of digital signals and th... In current wireless communication and electronic systems,digital signals and electromagnetic(EM)radiation are processed by different modules.Here,we propose a mechanism to fuse the modulation of digital signals and the manipulation of EM radiation on a single programmable metasurface(PM).The PM consists of massive subwavelength-scale digital coding elements.A set of digital states of all elements forms simultaneous digital information roles for modulation and the wave-control sequence code of the PM.By designing digital coding sequences in the spatial and temporal domains,the digital information and farfield patterns of the PM can be programmed simultaneously and instantly in desired ways.For the experimental demonstration of the mechanism,we present a programmable wireless communication system.The same system can realize transmissions of digital information in single-channel modes with beamsteerable capability and multichannel modes with multiple independent information.The measured results show the excellent performance of the programmable system.This work provides excellent prospects for applications in fifth-or sixth-generation wireless communications and modern intelligent platforms for unmanned aircrafts and vehicles. 展开更多
关键词 Joint radar and communication Programmable metasurface Massive multiple-in and multiple-out
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Application of U-Net and Optimized Clustering in Medical Image Segmentation:A Review 被引量:2
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作者 Jiaqi Shao Shuwen Chen +3 位作者 Jin Zhou Huisheng Zhu Ziyi Wang Mackenzie Brown 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2173-2219,共47页
As a mainstream research direction in the field of image segmentation,medical image segmentation plays a key role in the quantification of lesions,three-dimensional reconstruction,region of interest extraction and so ... As a mainstream research direction in the field of image segmentation,medical image segmentation plays a key role in the quantification of lesions,three-dimensional reconstruction,region of interest extraction and so on.Compared with natural images,medical images have a variety of modes.Besides,the emphasis of information which is conveyed by images of different modes is quite different.Because it is time-consuming and inefficient to manually segment medical images only by professional and experienced doctors.Therefore,large quantities of automated medical image segmentation methods have been developed.However,until now,researchers have not developed a universal method for all types of medical image segmentation.This paper reviews the literature on segmentation techniques that have produced major breakthroughs in recent years.Among the large quantities of medical image segmentation methods,this paper mainly discusses two categories of medical image segmentation methods.One is the improved strategies based on traditional clustering method.The other is the research progress of the improved image segmentation network structure model based on U-Net.The power of technology proves that the performance of the deep learning-based method is significantly better than that of the traditional method.This paper discussed both advantages and disadvantages of different algorithms and detailed how these methods can be used for the segmentation of lesions or other organs and tissues,as well as possible technical trends for future work. 展开更多
关键词 Medical image segmentation clustering algorithm U-Net
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CAD OF MILLIMETER WAVE OSCILLATORS WITH THE FDHB TECHNIQUE
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作者 蒋晓红 洪伟 朱晓维 《Journal of Electronics(China)》 1993年第3期243-248,共6页
In this paper the modelling, analysis and optimization of millimeter wave oscillatorsare investigated by using the a frequency-domain harmonic balance technique (FDHB), where theexternal-circuit impedances looking out... In this paper the modelling, analysis and optimization of millimeter wave oscillatorsare investigated by using the a frequency-domain harmonic balance technique (FDHB), where theexternal-circuit impedances looking outside from the active device are calculated with a combinedtechnique of modes expansion, Galerkin, and collocation methods. The optimization results arein agreement with the experimental ones, which show the reliability of the presented model andoptimization. 展开更多
关键词 MILLIMETER wave OSCILLATOR External-circuit IMPEDANCES Large-signal model of active devices HARMONIC BALANCE CAD
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On Differentiation Among Pilot Signals of Multiple Mobile Targets in Retro-Reflective Beamforming for Wireless Power Transmission
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作者 Xin Wang Long Li +1 位作者 Tie Jun Cui Mingyu Lu 《Engineering》 SCIE EI CAS CSCD 2023年第11期55-62,共8页
An experimental study is conducted on several retro-reflective beamforming schemes for wireless power transmission to multiple wireless power receivers(referred to herein as“targets”).The experimental results demons... An experimental study is conducted on several retro-reflective beamforming schemes for wireless power transmission to multiple wireless power receivers(referred to herein as“targets”).The experimental results demonstrate that,when multiple targets broadcast continuous-wave pilot signals at respective frequencies,a retro-reflective wireless power transmitter is capable of generating multiple wireless power beams aiming at the respective targets as long as the multiple pilot signals are explicitly separated from one another by the wireless power transmitter.However,various practical complications are identified when the pilot signals of multiple targets are not appropriately differentiated from each other by the wireless power transmitter.Specifically,when multiple pilot signals are considered to be carried by the same frequency,the wireless power transmission performance becomes heavily dependent on the interaction among the pilot signals,which is highly undesirable in practice.In conclusion,it is essential for a retro-reflective wireless power transmitter to explicitly discriminate multiple targets’pilot signals among each other. 展开更多
关键词 Wireless power transmission Microwave antenna array Retro-reflective beamforming Pilot signal Multiple access
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一种小型化人工表面等离激元传感系统——实现自适应和高灵敏的气体检测 被引量:1
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作者 Xuanru Zhang Jia Wen Zhu Tie Jun Cui 《Engineering》 SCIE EI CAS CSCD 2024年第4期86-94,共9页
Resonantly enhanced dielectric sensing has superior sensitivity and accuracy because the signal is measured from relative resonance shifts that are immune to signal fluctuations.For applications in the Internet of Thi... Resonantly enhanced dielectric sensing has superior sensitivity and accuracy because the signal is measured from relative resonance shifts that are immune to signal fluctuations.For applications in the Internet of Things(IoT),accurate detection of resonance frequency shifts using a compact circuit is in high demand.We proposed an ultracompact integrated sensing system that merges a spoof surface plasmon resonance sensor with signal detection,processing,and wireless communication.A softwaredefined scheme was developed to track the resonance shift,which minimized the hardware circuit and made the detection adaptive to the target resonance.A microwave spoof surface plasmon resonator was designed to enhance sensitivity and resonance intensity.The integrated sensing system was constructed on a printed circuit board with dimensions of 1.8 cm×1.2 cm and connected to a smartphone wirelessly through Bluetooth,working in both frequency scanning mode and resonance tracking mode and achieving a signal-to-noise ratio of 69 dB in acetone vapor sensing.This study provides an ultracompact,accurate,adaptive,sensitive,and wireless solution for resonant sensors in the IoT. 展开更多
关键词 Spoof surface plasmons Internet of Things Integrated sensing Resonance tracking Microwave sensing
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基于5 μm厚向列相液晶的高效圆极化相控阵系统的设计、校准和实验验证
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作者 Xin Yu Wu Fengshuo Wan +8 位作者 Hongyuan Feng Shichao Jin Chong Guo Yu Wei Dunge Liu Yuqian Yang Longzhu Cai Zhi Hao Jiang Wei Hong 《Engineering》 SCIE EI CAS CSCD 2024年第1期69-81,共13页
This paper presents a systematic investigation and demonstration of a K-band circularly polarized liquidcrystal-based phased array(LCPA),including the design,over-the-air(OTA)in-array calibration,and experimental vali... This paper presents a systematic investigation and demonstration of a K-band circularly polarized liquidcrystal-based phased array(LCPA),including the design,over-the-air(OTA)in-array calibration,and experimental validation.The LCPA contains 16 phase-shifting radiating channels,each consisting of a circularly polarized stacked patch antenna and a liquid-crystal-based phase shifter(LCPS)based on a loaded differential line structure.Thanks to its slow-wave properties,the LCPS exhibits a maximum phase-shifting range of more than 360°with a figure of merit of 78.3(°)·dB^(-1)based on a liquid crystal layer with a thickness of only 5μm.Furthermore,an automatic OTA calibration based on a state ergodic method is proposed,which enables the extraction of the phase-voltage curve of every individual LCPA channel.The proposed LCPA is manufactured and characterized with a total profile of only 1.76 mm,experimentally demonstrating a scanned circularly polarized beam from-40°to+40°with a measured peak gain of 12.5 dBic and a scanning loss of less than 2.5 dB.The bandwidth of the LCPA,which satisfies the require-ments of port reflection(|S_(11)|)<-15 dB,an axial ratio(AR)<3 dB,beam squinting<3°,and a gain variation<2.2 dB,spans from 25.5 to 26.0 GHz.The total efficiency is about 34%,which represents a new state of the art.The use of the demonstrated low-profile LCPA to support circularly polarized scanning beams,along with the systematic design and calibration methodology,holds potential promise for a variety of millimeter-wave applications. 展开更多
关键词 Circularly polarized Liquid crystal Liquid-crystal based phased array(LCPA) Phase shifter Over-the-air(OTA)calibration
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A Retrodirective Array Enabled by CMOS Chips for Two-Way Wireless Communication with Automatic Beam Tracking
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作者 Jiacheng Guo Yizhu Shen +2 位作者 Guoqing Dong Zhuang Han Sanming Hu 《Engineering》 SCIE EI CAS CSCD 2024年第6期196-207,共12页
This article proposes and demonstrates a retrodirective array(RDA)for two-way wireless communication with automatic beam tracking.The proposed RDA is enabled by specifically designed chips made using a domestic comple... This article proposes and demonstrates a retrodirective array(RDA)for two-way wireless communication with automatic beam tracking.The proposed RDA is enabled by specifically designed chips made using a domestic complementary metal-oxide semiconductor(CMOS)process.The highly integrated CMOS chip includes a receiving(Rx)chain,a transmitting(Tx)chain,and a unique tracking phaselocked loop(PLL)for the crucial conjugated phase recovery in the RDA.This article also proposes a method to reduce the beam pointing error(BPE)in a conventional RDA.To validate the above ideas simply yet without loss of generality,a 2.4 GHz RDA is demonstrated through two-way communication links between the Rx and Tx chains,and an on-chip quadrature coupler is designed to achieve a nonretrodirective signal suppression of 23 dBc.The experimental results demonstrate that the proposed RDA,which incorporates domestically manufactured low-cost 0.18 lm CMOS chips,is capable of automatically tracking beams covering±40with a reduced BPE.Each CMOS chip in the RDA has a compact size of 4.62 mm^(2) and a low power consumption of 0.15 W.To the best of the authors’knowledge,this is the first research to demonstrate an RDA with a fully customized CMOS chip for wireless communication with automatic beam tracking。 展开更多
关键词 Automatic beam tracking CMOS Retrodirective array Two-way communication
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Machine Learning for Signal Demodulation in Underwater Wireless Optical Communications
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作者 Ma Shuai Yang Lei +6 位作者 Ding Wanying Li Hang Zhang Zhongdan Xu Jing Li Zongyan Xu Gang Li Shiyin 《China Communications》 SCIE CSCD 2024年第5期297-313,共17页
The underwater wireless optical communication(UWOC)system has gradually become essential to underwater wireless communication technology.Unlike other existing works on UWOC systems,this paper evaluates the proposed ma... The underwater wireless optical communication(UWOC)system has gradually become essential to underwater wireless communication technology.Unlike other existing works on UWOC systems,this paper evaluates the proposed machine learningbased signal demodulation methods through the selfbuilt experimental platform.Based on such a platform,we first construct a real signal dataset with ten modulation methods.Then,we propose a deep belief network(DBN)-based demodulator for feature extraction and multi-class feature classification.We also design an adaptive boosting(Ada Boost)demodulator as an alternative scheme without feature filtering for multiple modulated signals.Finally,it is demonstrated by extensive experimental results that the Ada Boost demodulator significantly outperforms the other algorithms.It also reveals that the demodulator accuracy decreases as the modulation order increases for a fixed received optical power.A higher-order modulation may achieve a higher effective transmission rate when the signal-to-noise ratio(SNR)is higher. 展开更多
关键词 ADABOOST DBN machine learning signal demodulation
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Multi-layer network embedding on scc-based network with motif
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作者 Lu Sun Xiaona Li +4 位作者 Mingyue Zhang Liangtian Wan Yun Lin Xianpeng Wang Gang Xu 《Digital Communications and Networks》 SCIE CSCD 2024年第3期546-556,共11页
Interconnection of all things challenges the traditional communication methods,and Semantic Communication and Computing(SCC)will become new solutions.It is a challenging task to accurately detect,extract,and represent... Interconnection of all things challenges the traditional communication methods,and Semantic Communication and Computing(SCC)will become new solutions.It is a challenging task to accurately detect,extract,and represent semantic information in the research of SCC-based networks.In previous research,researchers usually use convolution to extract the feature information of a graph and perform the corresponding task of node classification.However,the content of semantic information is quite complex.Although graph convolutional neural networks provide an effective solution for node classification tasks,due to their limitations in representing multiple relational patterns and not recognizing and analyzing higher-order local structures,the extracted feature information is subject to varying degrees of loss.Therefore,this paper extends from a single-layer topology network to a multi-layer heterogeneous topology network.The Bidirectional Encoder Representations from Transformers(BERT)training word vector is introduced to extract the semantic features in the network,and the existing graph neural network is improved by combining the higher-order local feature module of the network model representation network.A multi-layer network embedding algorithm on SCC-based networks with motifs is proposed to complete the task of end-to-end node classification.We verify the effectiveness of the algorithm on a real multi-layer heterogeneous network. 展开更多
关键词 Semantic communication and computing Multi-layer network Graph neural network MOTIF
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IEEE 802.11aj(45GHz):A New Very High Throughput Millimeter-Wave WLAN System 被引量:10
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作者 WANG Haiming HONG Wei +2 位作者 CHEN Jixin SUN Bo PENG Xiaoming 《China Communications》 SCIE CSCD 2014年第6期51-62,共12页
This paper presents an overview of a new very high throughput millimeterwave WLAN system operating at 45 GHz band. We begin by reviewing standards process of IEEE 802.11aj(45GHz). Then the frequency spectrum allocatio... This paper presents an overview of a new very high throughput millimeterwave WLAN system operating at 45 GHz band. We begin by reviewing standards process of IEEE 802.11aj(45GHz). Then the frequency spectrum allocation at 45 GHz band is introduced. Next, the channel measurement and mod-eling is given. Specifically, the millimeter-wave MIMO for physical layer enhancement is given in detail. 展开更多
关键词 wireless local access network(WLAN) MILLIMETER-WAVE very highthroughput 45 GHz mul-tiple-input andmultiple-output (MIMO)
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Accuracy Improvement of GTEM Cells for EMI Noise Measurement 被引量:5
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作者 ZHAO Yang RONG Rong +4 位作者 ZHANG Yuhuan YAN Wei ZHAO Bo WANG Enrong QIU Xiaohui 《中国电机工程学报》 EI CSCD 北大核心 2012年第27期I0022-I0022,198,共1页
针对吉赫兹横电磁波fgigahertz transverse electromagnetic,GTEMl小室用于辐射电磁干扰(electromagnetic interference,EMI)测量精度不高的问题,提出一种GTEM小室测量EMI噪声的的校准方法,采用多项式模型提取辐射噪声,利用方差... 针对吉赫兹横电磁波fgigahertz transverse electromagnetic,GTEMl小室用于辐射电磁干扰(electromagnetic interference,EMI)测量精度不高的问题,提出一种GTEM小室测量EMI噪声的的校准方法,采用多项式模型提取辐射噪声,利用方差对该模型的计算误差进行补偿,并基于高阶矩分析校准后的GTEM小室和3m电波暗室测量辐射电场值分布的相似性。实验结果表明,采用该文所提方法可显著提高GTEM小室的测量精度,验证了方法的有效性。 展开更多
关键词 GTEM 噪声测量 EMI M细胞 测量精度 辐射测量 校准方法 横电磁波
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Three-dimensional simulation method of multipactor in microwave components for high-power space application 被引量:5
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作者 李韵 崔万照 +4 位作者 张 娜 王新波 王洪广 李永东 张剑锋 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期686-693,共8页
Based on the particle-in-cell technology and the secondary electron emission theory, a three-dimensional simulation method for multipactor is presented in this paper. By combining the finite difference time domain met... Based on the particle-in-cell technology and the secondary electron emission theory, a three-dimensional simulation method for multipactor is presented in this paper. By combining the finite difference time domain method and the panicle tracing method, such an algorithm is self-consistent and accurate since the interaction between electromagnetic fields and particles is properly modeled. In the time domain aspect, the generation of multipactor can be easily visualized, which makes it possible to gain a deeper insight into the physical mechanism of this effect. In addition to the classic secondary electron emission model, the measured practical secondary electron yield is used, which increases the accuracy of the algorithm. In order to validate the method, the impedance transformer and ridge waveguide filter are studied. By analyzing the evolution of the secondaries obtained by our method, multipactor thresholds of these components are estimated, which show good agreement with the experimental results. Furthermore, the most sensitive positions where multipactor occurs are determined from the phase focusing phenomenon, which is very meaningful for multipactor analysis and design. 展开更多
关键词 MULTIPACTOR numerical method THREE-DIMENSIONAL HIGH-POWER THRESHOLD
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Design and Implementation of An Active Multibeam Antenna System with 64 RF Channels and 256 Antenna Elements for Massive MIMO Application in 5G Wireless Communications 被引量:4
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作者 PANG Xingdong HONG Wei YANG Tianyang LI Linsheng 《China Communications》 SCIE CSCD 2014年第11期16-23,共8页
This paper focuses on the design and implementation of an active multibeam antenna system for massive MIMO applications in 5G wireless communications.The highly integrated active multibeam antenna system is designed a... This paper focuses on the design and implementation of an active multibeam antenna system for massive MIMO applications in 5G wireless communications.The highly integrated active multibeam antenna system is designed and implemented at 5.8 GHz with 64 RF Channels and 256 antenna elements.The 64-channel highly integrated active multibeam antenna system provides a verification platform for digital beamforming algorithm and massive MIMO channel estimation for next generation wireless communications. 展开更多
关键词 5G active multibeam antenna system digital beamforming Massive MIMO 5G wireless communications
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Multi-hop teleportation based on W state and EPR pairs 被引量:4
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作者 占海涛 余旭涛 +1 位作者 熊佩颖 张在琛 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第5期53-57,共5页
Multi-hop teleportation has significant value due to long-distance delivery of quantum information. Many studies about multi-hop teleportation are based on Bell pairs, partially entangled pairs or W state. The possibi... Multi-hop teleportation has significant value due to long-distance delivery of quantum information. Many studies about multi-hop teleportation are based on Bell pairs, partially entangled pairs or W state. The possibility of multi-hop teleportation constituted by partially entangled pairs relates to the number of nodes. The possibility of multi-hop teleportation constituted by double W states is (4/9)~n after n-hop teleportation. In this paper, a multi-hop teleportation scheme based on W state and EPR pairs is presented and proved. The successful possibility of quantum information transmitted hop by hop through intermediate nodes is deduced. The possibility of successful transmission is (2/3)~n after n-hop teleportation. 展开更多
关键词 multi-hop teleportation W state Bell pairs
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A Planar 4-Bit Reconfigurable Antenna Array Based on the Design Philosophy of Information Metasurfaces 被引量:3
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作者 Zheng Xing Wang Hanqing Yang +5 位作者 Ruiwen Shao Jun Wei Wu Guobiao Liu Feng Zhai Qiang Cheng Tie Jun Cui 《Engineering》 SCIE EI CAS 2022年第10期64-74,共11页
Inspired by the design philosophy of information metasurfaces based on the digital coding concept,a planar 4-bit reconfigurable antenna array with low profile of 0.15λ0(whereλ0is the free-space wavelength)is present... Inspired by the design philosophy of information metasurfaces based on the digital coding concept,a planar 4-bit reconfigurable antenna array with low profile of 0.15λ0(whereλ0is the free-space wavelength)is presented.The array is based on a digital coding radiation element consisting of a 1-bit magnetoelectric(ME)dipole and a miniaturized reflection-type phase shifter(RTPS).The proposed 1-bit ME dipole can provide two digital states of"0"and"1"(with 0°and 180°phase responses)over a wide frequency band by individually exciting its two symmetrical feeding ports.The designed RTPS is able to realize a relative phase shift of 173°.By digitally quantizing its phase in the range of 157.5°,additional eight digital states at intervals of 22.5°are obtained.To achieve low sidelobe levels,a 1:16 power divider based on the Taylor line source method is employed to feed the array,A prototype of the proposed 4-bit antenna array has been fabricated and tested,and the experimental results are in good agreement with the simulations.Scanning beams within a±45°range were measured with a maximum realized gain of 13.4 dBi at12 GHz.The sidelobe and cross-polarization levels are below-14.3 and-23.0 dB,respectively.Furthermore,the beam pointing error is within 0.8°,and the 3 dB gain bandwidth of the broadside beam is 25%.Due to its outstanding performance,the array holds potential for significant applications in radar and wireless communication systems. 展开更多
关键词 4-bit reconfigurable antenna array Information metasurface Digital coding method Low sidelobe Low profile
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A Low Power,High Sensitivity SiGe HBT Static Frequency Divider up to 90 GHz for Millimeter-Wave Application 被引量:2
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作者 Peigen Zhou Jixin Chen +2 位作者 Pinpin Yan Debin Hou Wei Hong 《China Communications》 SCIE CSCD 2019年第2期85-94,共10页
A layout and connection optimization for static frequency divider is presented. The layout optimization provides a new circle topology transistors placement and reasonable connection structure, which reduces the paras... A layout and connection optimization for static frequency divider is presented. The layout optimization provides a new circle topology transistors placement and reasonable connection structure, which reduces the parasitic effectively and enables self-oscillation frequency enhancement. Besides, bandwidth enhancement techniques based on a center-tap capacitor in input balun design and inductive peaking in latch design are adopted to improve further high frequency performance with low power consumption. As a proof of concept, design of a divide-by-2 static frequency divider in 0.13 μm SiGe BiCMOS technology is reported. With single-ended input clock signal, the divider is measured to be operated from 40 to 90 GHz. Phase noise measurements of a 90 GHz input clock signal indicate ideal behavior with no measurable noise contribution from the divider. The divider followed by a buffer that can deliver more than-10 dBm output power, which is sufficient to drive succeeding stage. To the author's knowledge, the divider exhibits a competitive power dissipation and the highest FOM among silicon based frequency dividers that operating higher than 70 GHz. 展开更多
关键词 E-band layout optimization MILLIMETER wave integrated circuits STATIC frequency DIVIDER SIGE
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A novel spoof surface plasmon polariton structure to reach ultra-strong field confinements 被引量:4
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作者 Pei Hang He Hao Chi Zhang +5 位作者 Xinxin Gao Ling Yun Niu Wen Xuan Tang Jiayuan Lu Le Peng Zhang Tie Jun Cui 《Opto-Electronic Advances》 2019年第6期9-15,共7页
Ultrathin corrugated metallic structures have been proved to support spoof surface plasmon polariton (SPP) modes on two-dimension (2D) planar microwave circuits.However,to provide stronger field confinement,larger wid... Ultrathin corrugated metallic structures have been proved to support spoof surface plasmon polariton (SPP) modes on two-dimension (2D) planar microwave circuits.However,to provide stronger field confinement,larger width of strip is required to load deeper grooves,which is cumbersome in modern large-scale integrated circuits and chips.In this work,a new spoof SPP transmission line (TL) with zigzag grooves is proposed.This new structure can achieve stronger field confinement compared to conventional one with the same strip width.In other words,the proposed spoof SPP TL behaves equivalently to a conventional one with much larger size.Dispersion analysis theoretically indicates the negative correlation between the ability of field confinement and cutoff frequencies of spoof SPP TLs.Numerical simulations indicate that the cutoff frequency of the proposed TL is lower than the conventional one and can be easily modified with the fixed size.Furthermore,two samples of the new and conventional spoof SPP TLs are fabricated for experimental demonstration.Measured S-parameters and field distributions verify the ultra-strong ability of field confinement of the proposed spoof SPP TL.Hence,this novel spoof SPP structure with ultra-strong field confinement may find wide applications in microwave and terahertz engineering. 展开更多
关键词 ULTRATHIN corrugated metallic STRUCTURE surface PLASMON POLARITONS field confinement ZIGZAG GROOVES
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COVID-19 Imaging Detection in the Context of Artificial Intelligence and the Internet of Things 被引量:1
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作者 Xiaowei Gu Shuwen Chen +1 位作者 Huisheng Zhu Mackenzie Brown 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第8期507-530,共24页
Coronavirus disease 2019 brings a huge burden on the medical industry all over the world.In the background of artificial intelligence(AI)and Internet of Things(IoT)technologies,chest computed tomography(CT)and chest X... Coronavirus disease 2019 brings a huge burden on the medical industry all over the world.In the background of artificial intelligence(AI)and Internet of Things(IoT)technologies,chest computed tomography(CT)and chest Xray(CXR)scans are becoming more intelligent,and playing an increasingly vital role in the diagnosis and treatment of diseases.This paper will introduce the segmentation of methods and applications.CXR and CT diagnosis of COVID-19 based on deep learning,which can be widely used to fight against COVID-19. 展开更多
关键词 COVID-19 medical image chest CT CXR IoMT AI
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