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Dual-Mode Resonant Sectorial Monopole Antenna with Stable Backfire Gain

Chinese Journal of Electronics 2024年第6期33卷 1478-1486页

作者： Feiyan JI Heng ZHANG Xiuqiong XING Wenjun LU Lei ZHU Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Department of Electrical and Computer Engineering Faculty of Science and Technology University of Macau

A novel design approach to wideband, dual-mode resonant monopole antenna with stable, enhanced backfire gain is advanced. The sectorial monopole evolves from a linear, 0.75-wavelength electric prototype monopole under wideband dual-mode resonant operation. As theoretically predicted by the two resonant modes TE3/5,1and TE9/5,1within a 150° radiator, the operation principle is revealed at first. As have been numerically demonstrated and experimentally validated at 2.4-GHz band, the designed antenna exhibits a wide impedance bandwidth over 90.1%（i.e., 2.06–5.44 GHz）, in which the stable gain bandwidth in the backfire,-x-direction（θ = 90°, φ = 180°） with peak value of 3.2 dBi and fluctuation less than 3 dB is up to 45.3%（i.e., 3.74–5.44 GHz）. It is concluded that the stable wideband backfire gain frequency response should be owing to the high-order resonant mode in the unique sectorial monopole antennas.

关键词： Fluctuations Azimuth Prototypes Metals Resonance Frequency measurement Broadband antennas Impedance Gain wideband

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Low-Complexity Estimation Algorithm and Decoupling Scheme for FRaC System

IEEE Transactions on Intelligent Vehicles

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IEEE Transactions on Intelligent Vehicles 2024年 1-12页

作者： Sun, Mengjiang Chen, Peng Cao, Zhenxin Shen, Fei State Key Laboratory of Millimeter Waves Southeast University Nanjing China Key Laboratory of Wireless Sensor Network and Communications Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China

With the leaping advances in autonomous vehicles and transportation infrastructure, dual function radarcommunication (DFRC) systems have become attractive due to the size, cost and resource efficiency. A frequency modulated continuous waveform (FMCW)-based radar-communication system (FRaC) utilizing both sparse multiple-input and multipleoutput (MIMO) arrays and index modulation (IM) has been proposed to form a DFRC system specifically designed for vehicular applications. In this paper, the three-dimensional (3D) parameter estimation problem in the FRaC is considered. Since the 3D-parameters including range, direction of arrival (DOA) and velocity are coupled in the estimating matrix of the FRaC system, the existing estimation algorithms cannot estimate the 3D-parameters accurately. Hence, a novel decomposed decoupled atomic norm minimization (DANM) method is proposed by splitting the 3D-parameter estimating matrix into multiple 2D matrices with sparsity constraints. Then, the 3D-parameters are estimated and efficiently and separately with the optimized decoupled estimating matrix. Moreover, the Cramer-Rao lower ´ bound (CRLB) of the 3D-parameter estimation are derived, and the computational complexity of the proposed algorithm is analyzed. Simulation results show that the proposed decomposed DANM method exploits the advantage of the virtual aperture in the existence of coupling caused by IM and sparse MIMO array and outperforms the co-estimation algorithm with lower computation complexity. IEEE

关键词： Computational complexity

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Dual Radial-Resonant Wide Beamwidth Circular Sector Microstrip Patch Antennas

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Chinese Journal of Electronics 2023年第4期32卷 710-719页

作者： MAO Xiaohui LU Wenjun JI Feiyan XING Xiuqiong ZHU Lei Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Department of Electrical and Computer Engineering Faculty of Science and Technology University of Macau

In this article, a design approach to a radial-resonant wide beamwidth circular sector patch antenna is advanced. As properly evolved from a U-shaped d ipole, a prototype magnetic dipole can be fit in the radial direction of a circular sector patch radiator, with its length set as the positive odd-integer multiples of onequarter wavelength. In this way, multiple TM0m（m = 1,2,...） modes resonant circular sector patch antenna with short-circuited circumference and widened E-plane beamwidth can be realized by proper excitation and perturbations. Prototype antennas are then designed and fabricated to validate the design approach. Experimental results reveal that the E-plane beamwidth of a dual-resonant antenna fabricated on air/Teflon substrate can be effectively broadened to 128°/120°, with an impedance bandwidth of 17.4%/7.1%, respectively. In both cases, the antenna heights are strictly limited to no more than 0.03-guided wavelength. It is evidently validated that the proposed approach can effectively enhance the operational bandwidth and beamwidth of a microstrip patch antenna while maintaining its inherent low profile merit.

关键词： Geometry Patch antennas Perturbation methods Prototypes Magnetic resonance Microstrip antennas Bandwidth

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A teacher-student based attention network for fine-grainedimage recognition

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Digital communications and networks 2025年第1期11卷 52-59页

作者： Ang Li Xueyi Zhang Peilin Li Bin Kang Key Laboratory of Broadband Wireless Communication and Sensor Network Technology(Ministry of Education) Nanjing University of Posts and TelecommunicationsNanjing210003China School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing210003China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China

Fine-grained Image Recognition(FGIR)task is dedicated to distinguishing similar sub-categories that belong to the same super-category,such as bird species and car *** order to highlight visual differences,existing FGIR works often follow two steps:discriminative sub-region localization and local feature ***,these works pay less attention on global context *** neglect a fact that the subtle visual difference in challenging scenarios can be highlighted through exploiting the spatial relationship among different subregions from a global view ***,in this paper,we consider both global and local information for FGIR,and propose a collaborative teacher-student strategy to reinforce and unity the two types of *** framework is implemented mainly by convolutional neural network,referred to Teacher-Student Based Attention Convolutional Neural network(T-S-ACNN).For fine-grained local information,we choose the classic Multi-Attention network(MA-Net)as our baseline,and propose a type of boundary constraint to further reduce background noises in the local attention *** this way,the discriminative sub-regions tend to appear in the area occupied by fine-grained objects,leading to more accurate sub-region *** fine-grained global information,we design a graph convolution based Global Attention network(GA-Net),which can combine extracted local attention maps from MA-Net with non-local techniques to explore spatial relationship among *** last,we develop a collaborative teacher-student strategy to adaptively determine the attended roles and optimization modes,so as to enhance the cooperative reinforcement of MA-Net and *** experiments on CUB-200-2011,Stanford Cars and FGVC Aircraft datasets illustrate the promising performance of our framework.

关键词： Fine-grained image recognition Collaborative teacher-student strategy Multi-attention Global attention

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Quality-Aware Massive Content Delivery in Digital Twin-Enabled Edge networks

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China communications 2023年第2期20卷 1-13页

作者： Yun Gao Junqi Liao Xin Wei Liang Zhou School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China

Massive content delivery will become one of the most prominent tasks of future B5G/6G ***,various multimedia applications possess huge differences in terms of object oriented(i.e.,machine or user)and corresponding quality evaluation metric,which will significantly impact the design of encoding or decoding within content delivery *** get over this dilemma,we firstly integrate the digital twin into the edge networks to accurately and timely capture Quality-of-Decision(QoD)or Quality-of-Experience(QoE)for the guidance of content ***,in terms of machinecentric communication,a QoD-driven compression mechanism is designed for video analytics via temporally lightweight frame classification and spatially uneven quality assignment,which can achieve a balance among decision-making,delivered content,and encoding ***,in terms of user-centric communication,by fully leveraging haptic physical properties and semantic correlations of heterogeneous streams,we develop a QoE-driven video enhancement scheme to supply high data *** results demonstrate the remarkable performance improvement of massive content delivery.

关键词： content delivery digital twin edge networks QoD QoE

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An RVT-based power allocation method for dynamic LEO-MEO links

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High technology Letters 2023年第1期29卷 1-11页

作者：潘坤贝 ZHOU Bin ZHAO Yu BU Zhiyong Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Key Laboratory of Wireless Sensor Network and Communications Chinese Academy of SciencesShanghai 200050P.R.China

Optimizing the power resources allocation method of low earth orbit(LEO)satellites to medium earth orbit(MEO)satellite'links is a significant way to construct efficient satellite constellations for satellite communication.A game theory power allocation method based on remaining visible time(RVT)of LEO-MEO satellites is ***,one LEO-MEO satellite network is classified as a cluster in which the RVT of LEO satellites is ***,the cost function of RVT concerning the character of orbit and throughput in each LEO satellite is mainly designed,which gives greater punishment of utility value to LEO satellites with less RVT and is an essential part of the reasonable utility function applied in diverse motion ***,the existence of Nash equilibrium for the proposed utility function in game theory area is ***,an off-cluster scheme for LEO satellites through the proposed threshold is raised to ensure the overall utility value of the whole LEO satellites in ***,the performance improvement of the proposed algorithm to the baseline algorithm is verified through simulations in different scenarios.

关键词： inter-satellite link power allocation remaining visible time(RVT) utility function motion trajectory(MT) game theory

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A General Framework for Intelligent IoT Data Acquisition and Sharing in an Untrusted Environment Based on Blockchain

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China communications 2024年第3期21卷 137-148页

作者： Lu Yin Xue Yongtao Li Qingyuan Wu Luocheng Li Taosen Yang Peipei Zhu Hongbo College of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China Research Institute of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing 210003China Bell Honors School Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Automation Nanjing University of Posts and TelecommunicationsNanjing 210023China

Traditional Io T systems suffer from high equipment management costs and difficulty in trustworthy data sharing caused by *** provides a feasible research direction to solve these problems. The main challenge at this stage is to integrate the blockchain from the resourceconstrained Io T devices and ensure the data of Io T system is credible. We provide a general framework for intelligent Io T data acquisition and sharing in an untrusted environment based on the blockchain, where gateways become Oracles. A distributed Oracle network based on Byzantine Fault Tolerant algorithm is used to provide trusted data for the blockchain to make intelligent Io T data trustworthy. An aggregation contract is deployed to collect data from various Oracle and share the credible data to all on-chain users. We also propose a gateway data aggregation scheme based on the REST API event publishing/subscribing mechanism which uses SQL to achieve flexible data aggregation. The experimental results show that the proposed scheme can alleviate the problem of limited performance of Io T equipment, make data reliable, and meet the diverse data needs on the chain.

关键词： blockchain data sharing Internet of Things Oracle

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From Universe to Metaverse: IRS-Assisted Efficient Transmission for Hybrid Earth-Moon network 100

From Universe to Metaverse: IRS-Assisted Efficient Transmiss...

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100th IEEE Vehicular technology Conference, VTC 2024-Fall

作者： Lv, Chengcheng Shen, Fei Yan, Feng Shen, Lianfeng Wu, Yi Tang, Liang Zhao, Yu Bu, Zhiyong Chinese Academy of Sciences Key Laboratory of Wireless Sensor Network and Communications Shanghai Institute of Microsystem and Information Technology Shanghai200050 China University of Chinese Academy of Sciences Beijing100049 China Southeast University National Mobile Communications Research Laboratory Nanjing210096 China Fujian Normal University Fujian Provincial Engineering Technology Research Center of Photoelectric Sensing Application Fuzhou350007 China Shanghai Spacecom Satellite Technology Ltd. Shanghai201600 China

ISBN: (纸本)9798331517786

To fulfill the requirements of human lunar exploration programs and establish bases on the moon in the distant future, lunar sensors (LSs) will inevitably produce a significant amount of data. It is necessary to construct the Earth-Moon metaverse in order to obtain and utilize lunar information more effectively. Due to the long communication distance between Earth and Moon as well as the lack of communication resources, a hybrid Earth-Moon metaverse network with channel model and transmission model is designed. To ensure the efficiency and stability of transmission in the network, LSs transmit lunar data to Earth clients (ECs) through the active and passive intelligent reflecting surface (IRS) deployed at relay satellites. Then, we propose a Stackelberg game model to describe the adversarial relationship between the satellites, LSs and ECs, and optimal strategies are obtained by solving the Nash equilibrium to maximize their utility. Simulations demonstrate that the network can effectively shorten the transmission delay and improve the utility of ECs and satellites. © 2024 IEEE.

关键词： Lunar missions

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Task Offloading for Fog-Based Meta networks: An Energy and Delay Aware Mechanism

Task Offloading for Fog-Based Meta Networks: An Energy and D...

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2023 IEEE International Conference on Metaverse Computing, networking and Applications, MetaCom 2023

作者： Lv, Chengcheng Shen, Fei Yan, Feng Cao, Lili Wang, Chao Zhang, Yueyue Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Key Laboratory of Wireless Sensor Network and Communications Shanghai200050 China University of Chinese Academy of Sciences Beijing101408 China Southeast University National Mobile Communications Research Laboratory Nanjing210096 China Shanghai Aerospace Electronic Technology Institute Shanghai201109 China Shanghai Huace Navigation Technology Ltd Shanghai China

ISBN: (纸本)9798350333336

In recent years, with the rapid breakthrough and innovation of mobile communication, the meta network has become a crucial technology in people's daily life. Cloud computing, as the most widely used ways of task processing and data storage in the meta network system, can not support the diversified applications. Fog computing is a new computing mode that expands cloud computing to the clients. It can effectively reduce the burden of cloud server processing large-scale data. However, few research can give an appropriate task offloading strategy considering the specific needs of clients for time delay and energy resource. So, this paper proposed a meta task offloading mechanism based on time delay and energy resouce priority. This mechanism can effectively shorten the delay of clients' meta tasks, reduce energy resource, and ensure the income of fog nodes. And Stackelberg game theory is used to model the interaction between clients and fog nodes. Then, the optimal offloading strategy is obtained. Finally, We propose an Energy and Delay Awared Task Offloading(EDATO) algorithm. This algorithm can effectively improve the utility of clients and fog nodes according to clients' demand for time delay and energy resource. © 2023 IEEE.

关键词： Fog

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A Novel Grant-Free Random Access Scheme for mMTC 23

A Novel Grant-Free Random Access Scheme for mMTC

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23rd IEEE International Conference on Communication technology, ICCT 2023

作者： Zhao, Xuyuan Liu, Yang Wang, Cheng-Xiang School of Internet of Things Engineering Jiangnan University Wuxi214122 China Shanghai Institute of Microsystem and Information Technology Key Laboratory of Wireless Sensor Network and Communication Shanghai200050 China School of Information Science and Engineering Southeast University National Mobile Communications Research Laboratory Nanjing210096 China Purple Mountain Laboratories Nanjing211111 China

ISBN: (纸本)9798350325959

Grant-free (GF) random access is a promising technique to support massive machine-type communication (mMTC) systems. Due to the conflicts, the performance is degraded. The repeated transmission of packets reduces the probability of conflict. In this paper, we propose a novel GF random access scheme with retransmissions. An optimal preamble allocation method is proposed to determine the size of the retransmission preamble pool. Numerical simulations are performed to validate the theoretical analysis. The proposed scheme adapts to various mMTC scenarios. © 2023 IEEE.

关键词： grant-free(GF) performance analysis preamble allocation retransmissions

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