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International Conference on microwave and Millimeter Wave technology Proceedings

作者： Wenlu Qiu Jinxin Li Pei Xiao Zhu Liu Jun Dong College of Computer Science and Electronic Engineering Hunan University Changsha Hunan P. R. China National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications Nanjing P.R. China College of Electrical and Information Engineering Hunan University Changsha Hunan P. R. China School of Physics and Electronics Hunan Normal University Changsha Hunan P. R. China College of Information Science and Engineering Hunan Normal University Changsha Hunan P. R. China

ISBN: (纸本)9781665482271

A planar anisotropic metasurface superstrate structure for isolation enhancement of two closely packed antennas is proposed in this paper. The spacing of the initial antennas is only 0.12 $\lambda_{0}$ at 3.55 GHz $(\lambda_{0}$ is the wavelength at the center frequency). The metasurface structure is consists of periodic rectangular-loop unit resonators, which are printed on the one side of 1.5 mm thick FR-4 substrate in E-plane. By placing the decoupling structure beside the initial antennas instead of putting it in the middle of the antennas, it can reject coupling wave propagation and improve isolation of two ports of the antenna further. The simulated results show that the proposed metasurface structure is able to achieve port isolation improvement at least 19.7dB and at most 31.9dB with in the operation band from 3.3 to 3.8 GHz. More importantly, the antenna still keeps good performance with $\mathrm{S} < -10$ dB and has tendency to broaden bandwidth, while the metasurface superstrate structure is loaded.

关键词： microwave antennas Mutual coupling Resonant frequency Metasurfaces Broadband antennas Resonators Antennas

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Self-powered solar-blind photodiodes based on EFG-grown(100)-dominant β-Ga_(2)O_(3) substrate

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Chinese Physics B 2021年第1期30卷 483-486页

作者： Xu-Long Chu Zeng Liu Yu-Song Zhi Yuan-Yuan Liu Shao-Hui Zhang Chao Wu Ang Gao Pei-Gang Li Dao-You Guo Zhen-Ping Wu Wei-Hua Tang Laboratory of Information Functional Materials and Devices School of Science&State Key Laboratory of Information Photonics and Optical CommunicationsBeijing University of Posts and TelecommunicationsBeijing 100876China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China The Engineering Research Center for Semiconductor Integrated Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China China Aerospace System Simulation Technology Co. Ltd.(Beijing)Beijing 100195China Division of Interdisciplinary and Comprehensive Research&Platform for Characterization and Test Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Center for Optoelectronics Materials and Devices&Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhou 310018China School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China College of Electronic and Optical Engineering&College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210046China National and Local Joint Engineering Laboratory for RF Integration and Micro-Packing Technologies Nanjing University of Posts and TelecommunicationsNanjing 210046China

We report the edge-defined-film-fed(EFG)-grown β-Ga_(2)O_(3)-based Schottky *** device has a reverse leakage current of ~nA and a rectified ratio of ~10^(4) at ±5 *** addition,the photodiode detector shows a dark current of 0.3 pA,a photo-responsivity(R) of 2.875 mA/W,a special detectivity(D*) of 10^(10) Jones,and an external quantum efficiency(EQE) of 1.4% at zero bias,illustrating a self-powered *** work may advance the development of the Ga_(2)O_(3)-based Schottky diode solar-blind photodetectors.

关键词： β-Ga_(2)O_(3)substrate Schottky photodiode solar-blind detection

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Corrigendum to ‘Mist CVD technology for gallium oxide deposition: A review’ [Mater. Today Phys. 49(2024) 101604]

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Materials Today Physics 2025年 50卷

作者： Suhao Yao Yifan Yao Maolin Zhang Xueqiang Ji Shan Li Weihua Tang Innovation Center for Gallium Oxide Semiconductor (IC-GAO) College of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications Nanjing 210023 China National and Local Joint Engineering Laboratory for RF Integration and Micro-Packing Technologies Nanjing University of Posts and Telecommunications Nanjing 210023 China

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Energy Efficient Resource Allocation in NOMA-Sectored Heterogeneous Network

Energy Efficient Resource Allocation in NOMA-Sectored Hetero...

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International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Lei Wang Wen Tang Ting Qi Jingwu Cui Baoyu Zheng Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education China National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications China

ISBN: (数字)9781728172361

ISBN: (纸本)9781728172378

Non-orthogonal multiple access (NOMA) and heterogeneous network (HetNet) have been regarded as two promising technologies in 5G, which can support massive connectivity. Integrating NOMA technology into HetNet is an inevitable trend to achieve better spectral efficiency. However, interference control becomes more complicated due to the combination of these two technologies and the optimization of energy efficiency comes at the expense of spectral efficiency. Therefore, we develop a novel network scenario, which exploits the benefits of sectorization. In this paper, we aim to maximize the energy efficiency of the entire small cells in an uplink underlaying two-tier NOMA heterogeneous network with sectorization. Since this energy efficiency maximization problem is a mixed integer non-linear programming (MINLP) problem which is difficult to solve, it is decomposed into two subproblems. Firstly, we use the Lagrange dual method and Karush-Kuhn-Tucker (KKT) optimal conditions to obtain the closed-form power allocation solution. Secondly, a low-complexity subchannel allocation algorithm based on the greedy strategy is proposed. Simulation results show that our proposed scheme obtain significant energy efficiency gain and is superior to other existing schemes.

关键词： Resource management NOMA Uplink Base stations Heterogeneous networks Telecommunications Mathematical model

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Arbitrary-Oriented Ship Detection Based on Feature Filter and KL Loss

Arbitrary-Oriented Ship Detection Based on Feature Filter an...

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International Conference on Wireless Communications and Signal Processing (WCSP)

作者： Chen Li Lei Wang Bin Kang Mingkai Chen Jingwu Cui Baoyu Zheng Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education China National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications China

ISBN: (数字)9781728172361

ISBN: (纸本)9781728172378

Although deep learning has been dominant in the field of target detection, there are still some challenges in the field of detection of ships: horizontal boundary box contains too much redundancy and noise in the scene of large scale and dense arrangement of ships, and there are many interferences in remote sensing optical images that affect the bounding box regression. Recent neural network for ship detection is generally used to extract the pixel information in the image to achieve rapid positioning and boundary box regression, or to process the dataset, so as to train a more robust network. However, these methods do not focus on the original feature map and loss functions of the target, which directly lead to the effects of ship positioning and regression. In this paper, we propose a ship detection network based on feature filter and Kullback-Leibler (KL) divergence loss function. In this paper, we propose to use mask filters on the output of the region of interest (ROI) network to remove the noise around the rotating bounding box, which is conducive to the regression of the rotating bounding box and angle in the second stage. In order to get a better bounding box, we propose to use KL loss function for regression of bounding box parameters. With the optimization of KL loss, the bounding box can better surround the ship. We carried out experiments on our own remote sensing ship image dataset for ship detection, it contains 5,126 remote sensing satellite images and more than 23800 ships in 6 categories. The dataset contains a variety of scenarios and challenges. Experiments show that the method is accurate and effective, and the bounding box has good wrapping property.

关键词： Marine vehicles Feature extraction Remote sensing Object detection Redundancy Interference Proposals

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Design of a CMOS Distributed Power Amplifier with Gradual Changed Gain Cells

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Chinese Journal of Electronics 2018年第6期27卷 1158-1162页

作者： ZHANG Ying LI Zeyou YANG Hua GENG Xiao ZHANG Yi College of Electronic and Optical Engineering College of Microelectronics Nanjing University of Posts and Telecommunications National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications

A non-uniform Distributed power amplifier(DPA) is designed and implemented in a 0.18μm CMOS technology. The gradual changed gain cells work with the tapered on-chip inductors to construct non-uniform artificial transmission lines, which improves the output power and efficiency in a wide frequency band while maintaining good input and output impedance matching. The proposed DPA achieves 9 dB average associated gain from 1 to 17.2 GHz, and the input return loss is less than--9 dB while the output return loss is less than-8.5 dB in the desired frequency band. The output power at 1 dB Output compression point(OP1 dB) is more than 7.8 dBm in the frequency band of 2-16 GHz, and the peak power-added efficiency is 6.2% with the OP1 dB12.6 dBm at 4 GHz.

关键词： Distributed amplifier Impedance matching Power added efficiency Artificial transmission line

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12-bit 2.6 GS/s rf DAC based on return-to-zero technology

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The Journal of China Universities of Posts and Telecommunications 2019年第4期26卷 36-42页

作者： Li Xiaopeng Wang Zhigong Zhang Yi Zhang Youtao Zhang Mi Institute of RF and OE ICs Southeast UniversityNanjing 210096China Nanjing Guobo Electronics Company Limited Nanjing 210016China Nanjing Electronic Devices Institute Nanjing 210016China National and Local Joint Engineering Laboratory of RF Integration and Micro-assembly Technology Nanjing 210046China College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210046China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China Science and Technology on Monolithic Intergrated Circuits and Modules Laboratory Nanjing 210016China

A 12-bit 2.6 GS/s radio frequency digital to analog converter(rf DAC)based on 1 um GaAs heterojunction bipolar transistor(HBT)process is *** DAC integrates a 4:1 multiplexer to reduce the data rate of input ports,which greatly facilitates the *** core adopts 4+8 segmented current steering structure.R-2R ladder network is used for 8 least significant bit(LSB)to realize binary current weighting and thermometer coding is used for 4 most significant bit(MSB).Return-to-zero(RZ)technology is used to expand the effective bandwidth of DAC output to the third Nyquist *** proposed DAC has a better output power flatness and spurious-free dynamic range(SFDR).Compared to traditional DAC,measured results demonstrate that the output power of this RZ DAC is increased by 33 dB and the SFDR is enhanced by 27 dB near the second Nyquist band.

关键词： DAC RZ Nyquist band

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Circularly Polarized Leaky-wave Antenna Based on SubstrateIntegrated Waveguide Space Harmonic

Circularly Polarized Leaky-wave Antenna Based on SubstrateIn...

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International Symposium on Antennas and Propagation (ISAP)

作者： Yangjun Hu Leilei Liu Yangbing Jiang Dingwei Jiang Minghong Chen National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications Nanjing China

A circularly polarized leaky-wave antenna (LWA) is implemented on the substrate integrated waveguide (SIW) based on space harmonic radiation. The LWA cuts the current in two different directions by opening a cross-shaped slot on the substrate integrated waveguide. It realizes circular polarization and frequency sweeping characteristics by adjusting parameters of the slot. The antenna achieves a sweep range of 36°~13° in the θ direction backward radiation by -1 space harmonic from 15GHz to 17GHz. The gain is basically above 13.5dB. Parameters of the cross-shaped slot on the antenna performance are studied. The antenna is fabricated and the measurement results are agree well with the simulation ones.

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Resource allocation for indoor self-blockage WmWave device-to-device communications

TechRxiv

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TechRxiv 2020年

作者： Wang, Lei Yu, Xiaoting Zheng, Baoyu Yao, Jiming Gui, Guan National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications Nanjing210023 China National Mobile Communications Research Laboratory Southeast University Nanjing210096 China Global Energy Interconnection Research Institute Co. Ltd. Beijing100031 China

Millimeter wave (mmWave) technology can meet the requirements of large amount of data communications among intelligent devices for indoor scenario. With high requirement of throughput, reducing interference in an enclosed region is still a challenge. For indoor scenario, the human bodies are considered as the main blockages besides conventional blockages. In this paper, we present a new system model by exploiting the self-blockage model to capture the effects of human body, while using multi-ball Line of Sight (LOS) link state model to describe the conventional blockage. The combination of the two components provides a more comprehensive and accurate expression of indoor obstruction. We give a closed expression of coverage rate to analyze the system performance. Simulation results show that the proposed model is highly accurate to describe the distribution of blockages for indoor case. Then, we formulate the resource allocation as an optimization problem under this scenario. The target of this optimization is to achieve the maximum throughput by minimizing interference. To reach this goal, an improved Powell Multi Vertex Coloring algorithm (PMVC) is proposed. The throughput raises apparently when we modify this scheme to put more flows in different time-slots evenly. Numerical experiments show that the improved algorithm can achieve higher system throughput than traditional greedy algorithm and Powell Vertex Coloring (PVC) scheme. © 2020, CC BY.

关键词： Millimeter waves

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Fused Confidence for Scene Text Detection via Intersection-over-Union 19

Fused Confidence for Scene Text Detection via Intersection-o...

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19th IEEE International Conference on Communication technology, ICCT 2019

作者： Zhang, Guo-Lin Ge, Li-Li Yang, Yu-Nuo Liu, Yu-Qi Sun, Ke-Xue Nanjing University of Posts and Telecommunications College of Electronic and Optical Engineering Nanjing Jiangsu210003 China Radiofrequency Integration and Micro Assembly Technology National and Local Joint Engineering Lab Nanjing Jiangsu210003 China

ISBN: (纸本)9781728105352

CNN-based scene text detection methods have achieved superior results. They are mostly implemented on the architecture of full convolution networks and non-maximum suppression (NMS) which combines two tasks of text classification and localization. However, in the NMS procedure, most filter the bounding boxes according to the classification confidence. This makes appropriately those well-located text boxes suppressed during NMS. In this paper, we propose an intersection-over-union (IOU) network to predict the IOU between the bounding box and the matched ground-truth. Then, the predicted IOU as localization confidence will be fused with the classification confidence. Furthermore, in the NMS, the classification confidence is replaced by the fused confidence as the ranking standard to preserve the accurately located text boxes. We experimented on the ICDAR2011 and ICDAR2013 datasets, the results show that the method proposed in this paper can effectively improve the accuracy of text detection. © 2019 IEEE.

关键词： Classification (of information)

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