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7th International Conference on Computer and communications, ICCC 2021

作者： Pan, Conglin Chen, Si Wu, Wei Qian, Jiachuan Wang, Lijun No.36 Research Institute of CETC Science and Technology On Communication Information Security Control Laboratory Jiaxing China School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing China

ISBN: (纸本)9781665409506

MIMO technology has been widely used in the telecommunication systems nowadays, and the space-time coding is a key part of MIMO technology. A good coding scheme can exploit the spatial diversity to correct the error which is generated in transmission, and increase the normalized transfer rate with low decoding complexity. On the Basis of the research on different Space-Time Block Codes, this essay proposes a new STBC, Diagonal Block Orthogonal Space-Time Block Code. Then we will compare it with other STBCs in the performance of bit error rate, transfer rate, decoding complexity and peek-to-average power ratio, the final result will prove the superiority of DBOAST. © 2021 IEEE.

关键词： MIMO systems

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A Novel Integer Frequency Offset Estimation Method for OFDM Based on Preamble 7

A Novel Integer Frequency Offset Estimation Method for OFDM ...

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7th IEEE International Conference on Network Intelligence and Digital Content, IC-NIDC 2021

作者： Liu, Xinxin Xu, Zhan Tian, Lu Yang, Xiaolong Beijing Information Science and Technology University Key Laboratory of Modern Measurement and Control Technology Beijing100101 China School of Information and Communication Engineering Beijing Information Science and Technology University Beijing100101 China

ISBN: (纸本)9781665405829

Orthogonal frequency division multiplexing (OFDM) is very sensitive to frequency offset. Although the existence of integer frequency offset in OFDM will not destroy the orthogonality between subcarriers, it will cause a cyclic shift of the frequency domain data after FFT transformation at the receiving end, which will affect the demodulation of data. In this paper, we propose a novel integer frequency offset estimation method based on the similarity property of adjacent subcarriers of the preamble. This method not only guarantees the original accuracy and performance of the conventional method but also achieves less resource consumption and lower computational complexity. © 2021 IEEE.

关键词： Orthogonal frequency division multiplexing

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Two Enhanced-rate Power Allocation Strategies for Active IRS-assisted Wireless Network

arXiv

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arXiv 2023年

作者： Cheng, Qiankun Dong, Rongen Cai, Wenlong Liu, Ruiqi Shu, Feng Wang, Jiangzhou The School of Information and Communication Engineering Hainan University Haikou570228 China The School of Information and Communication Engineering Collaborative Innovation Center of Information Technology Hainan University Haikou570228 China The School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing210094 China National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing Aerospace Automatic Control Institute Beijing China The Wireless and Computing Research Institute ZTE Corporation Beijing100029 China The School of Engineering University of Kent CanterburyCT2 7NT United Kingdom

Due to its ability of overcoming the impact of double-fading effect, active intelligent reflecting surface (IRS) has attracted a lot of attention. Unlike passive IRS, active IRS should be supplied by power, thus adjusting power between base station (BS) and IRS having a direct impact on the system rate performance. In this paper, the active IRS-aided network under a total power constraint is modeled with an ability of adjusting power between BS and IRS. Given the transmit beamforming at BS and reflecting beamforming at IRS, the SNR expression is derived to be a function of power allocation (PA) factor, and the optimization of maximizing the SNR is given. Subsequently, two high-performance PA strategies, enhanced multiple random initialization Newton's (EMRIN) and Taylor polynomial approximation (TPA), are proposed. The former is to improve the rate performance of classic Netwon's method to avoid involving a local optimal point by using multiple random initializations. To reduce its high computational complexity, the latter provides a closed-form solution by making use of the first-order Taylor polynomial approximation to the original SNR function. Actually, using TPA, the original optimization problem is transformed into a problem of finding a root for a third-order polynomial. Simulation results are as follows: the first-order TPA of SNR fit its exact expression well, the proposed two PA methods performs much better than fixed PA in accordance with rate, and appoaches exhaustive search as the number of IRS reflecting elements goes to large-scale. Copyright © 2023, The Authors. All rights reserved.

关键词： Polynomial approximation

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Adaptive neural network output-feedback tracking control for switched nonlinear ship maneuvering systems with time delays under arbitrary switching

Adaptive neural network output-feedback tracking control for...

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2022 Chinese Automation Congress, CAC 2022

作者： Li, Zhenhua Ren, Xiangxuan Dong, Botao Chen, Hong Zhang, Weidong SJTU Sanya Yazhou Bay Institute of Deepsea Science and Technology Sanya572024 China Department of Automation Shanghai Jiao Tong University Shanghai200240 China College of Mechatronics and Control Engineering Shenzhen University Shenzhen518061 China School of Information and Communication Engineering Hainan University Haikou570228 China

ISBN: (纸本)9781665465335

This paper focuses on the tracking control problem for switched nonlinear ship maneuvering time-delay systems with only a heading angle available by adaptive neural network (NN) output feedback. Using the backstepping method, an adaptive NN control mechanism is designed to solve the problem cooperated with the state observer. The uncertain terms of the system are approximated by NNs, and the state observer is designed to estimate the yaw rate and rudder angle. The unknown time delays are overcome by exploiting the common Lyapunov-Krasovskii functionals (CLKFs). Combined with error transformation, the proposed control method guarantees that i) all of the signals for the system are semi-global uniformly ultimately boundedness (SGUUB) under arbitrary switching;and, ii) the tracking error of system output keeps within a small neighborhood around the origin. The results of simulation results are shown to demonstrate the feasibility of the control strategy. © 2022 IEEE.

关键词： Time delay

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Dynamic Tracking of Ship Course with Limited Input Based on ZG control and Bivariate S-Function

Dynamic Tracking of Ship Course with Limited Input Based on ...

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第34届中国控制与决策会议

作者： Shengmian Xie Yunong Zhang Jinjin Guo Mengling Xiao School of Information and Communication Engineering Guangzhou Maritime University Guangdong Key Laboratory of Modern Control Technology School of Computer Science and Engineering Sun Yat-sen University

The nonlinear control system of ship is complex,which is a focus of research and key core of dynamic *** the input of the actual system is often restricted by the physical constraints of the actuator and energysaving control,the feasible region of the control input is often constrained by these ***,by combining Zhang-gradient(ZG) dynamics with S-function,in this paper,a novel controller for the limited input system is *** the fact that dynamic systems are generally nonlinear in practical applications,the nonlinear system study has more practical ***,this paper extends the ZG control method based on gradient dynamics and the bivariate S-function to the tracking control of nonlinear ship system,and designs a ship course tracking controller with a limited input,which can control the rudder angle within a certain feasible region while successfully tracking the ship course.

关键词： Dynamic tracking Zhang-gradient(ZG) dynamics Bivariate S-function Limited input Nonlinear ship system

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Joint Optimization of UAV Deployment and Directional Antenna Orientation for Multi-UAV Cooperative Sensing

Joint Optimization of UAV Deployment and Directional Antenna...

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IEEE Conference on Wireless communications and Networking

作者： Lingyun Zhou Wenqiang Pu Ming-yi You Rongqing Zhang Qingjiang Shi School of Software Engineering Tongji University Shanghai China Shenzhen Research Institute of Big Data Shenzhen China Science and Technology on Communication Information Security Control Laboratory Jiaxing China

In this paper, we consider the problem of cooperative sensing via a system of multi-unmanned aerial vehicles (UAVs), where each UAV is equipped with a directional antenna to cooperatively perform detection tasks for several targets of interest. To measure the perception ability of the system, we choose the detection probability as the metric, aiming to maximize the sum detection probability of targets by jointly optimizing UAVs’ deployment and directional antenna orientations. To tackle the inherent nonconvexity of the formulated problem, we first decompose it into two sub-problems, i.e., a slave problem for optimizing the antenna orientations with a given UAVs’ deployment, and a master problem for optimizing the UAVs’ deployment. By virtue of the slave problem structure, an efficient block coordinate descent (BCD) algorithm is developed. Meanwhile, to deal with the lack of the closed expression of the sum detection probability with respect to the UAVs’ deployment, we further develop an iterative algorithm to acquire an efficient solution with the aid of Gibbs Sampling (GS) approach. Extensive simulations demonstrate the efficacy of the proposed algorithm.

关键词： Antenna measurements Directional antennas Autonomous aerial vehicles Sensors Iterative methods Task analysis Optimization

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A Robust Two-Dimensional DOA Estimation Approach Based on Convolutional Attention Network

A Robust Two-Dimensional DOA Estimation Approach Based on Co...

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International Joint Conference on Neural Networks (IJCNN)

作者： Rui Xiao Ming–Yi You Rui Zhou Qingjiang Shi School of Software Engineering Tongji University Shanghai China Science and Technology on Communication Information Security Control Laboratory Jiaxing China Shenzhen Research Institute of Big Data Shenzhen China

The direction of arrival (DOA) estimation of the signal is an important task in radio signal positioning. Various methods have been investigated to cope with the DOA task. However, since the imperfect interference factors are often present in practical antenna arrays, the performance of DOA estimation is often significantly degraded. Besides, few methods deal with the DOA estimation for signals of multiple frequencies. In this paper, we consider the problem of two-dimensional DOA estimation in the presence of imperfect factors, and propose a novel approach where the convolutional attention network is used for DOA estimation. The frequency information is introduced as a token added to the network, which improves the network robustness while taking into account the case of the signal of multiple frequencies. Besides, we extend the mean square error (MSE) to the design of a new loss function for training to improve the accuracy of the model. The advantages of the proposed DOA estimation scheme are demonstrated through numerical experiments.

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Fault Diagnosis Method of Rolling Bearings Under Different Working Conditions Based on Federated Feature Transfer Learning

Fault Diagnosis Method of Rolling Bearings Under Different W...

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Sensing, measurement & Data Analytics in the era of Artificial Intelligence (ICSMD), International Conference on

作者： Shouqiang Kang Jiawei Yang Yulin Sun Yujing Wang Qingyan Wang V.I. Mikulovich School of Measurement-Control and Communication Engineering Harbin University of Science and Technology Harbin China Belarusian State University Minsk Belarus

A rolling bearing fault diagnosis method based on the federated feature transfer learning is proposed for the low accuracy of the diagnosis model in the presence of large differences in data distribution under different working conditions, difficulty in obtaining labeled data and non-sharing of data among different users. This method performs wavelet transformation on the time domain vibration data of rolling bearings to obtain a time-frequency diagram. The priori labeled public data and the multi-user island private data are regarded as the source domain and the target domain. The multi-representation feature extraction structure is introduced to improve the original residual network. Based on an improved residual network and multi-representation features in the source domain and the target domain, every local model and a federated global model are constructed. Through verification of bearing data, the proposed method can establish an effective fault diagnosis model with high fault diagnosis accuracy. It can integrate the knowledge of isolated island data without sharing data among multiple users.

关键词： Fault diagnosis Employee welfare Wavelet transforms Adaptation models Wavelet domain Transfer learning Rolling bearings

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A Collaborative Jamming Algorithm Based on Multi-UAV Scheduling

A Collaborative Jamming Algorithm Based on Multi-UAV Schedul...

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International Conference on communication technology (ICCT)

作者： Yixin Jiang Lingyun Zhou Yijia Tang Ya Tu Chunhong Liu Qingjiang Shi School of Software Engineering Tongji University Shanghai China Science and Technology on Communication Information Security Control Laboratory Jiaxing China Shenzhen Research Institute of Big Data Shenzhen China

In this paper, we consider the problem of multi-unmanned aerial vehicles' (UAVs), scheduling for cooperative jamming, where UAVs equipped with directional antennas perform collaborative jamming tasks against several targets of interest. To ensure effective jamming towards the targets, we formulate it as an non-convex optimization problem, aiming to minimize the communication performance of the targets by jointly optimizing UAVs' deployment and directional antenna orientations. Due to the unique structure of the problem, we derive an equivalent transformation by introducing a set of auxiliary matrices. Subsequently, we propose an efficient iterative algorithm based on the alternating direction method of multi-pliers (ADMM), which decomposes the problem into multiple tractable subproblems solved in closed-form or by gradient projection method. Extensive simulations validate the efficacy of the proposed algorithm.

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Characterizing Human Collective Behaviors During COVID-19 — Hong Kong SAR, China, 2020

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China CDC weekly 2023年第4期5卷 71-75,I0001-I0003页

作者： Zhanwei Du Xiao Zhang Lin Wang Sidan Yao Yuan Bai Qi Tan Xiaoke Xu Sen Pei Jingyi Xiao Tim K.Tsang Qiuyan Liao Eric H.YLau Peng Wu Chao Gao Benjamin J.Cowling WHO Collaborating Centre for Infectious Disease Epidemiology and Control School of Public HealthLi Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina Laboratory of Data Discovery for Health Hong Kong Science and Technology ParkNew TerritoriesHong Kong Special Administrative RegionChina Department of Genetics University of CambridgeCambridgeCB23EHUK Institute of High Performance Computing(IHPC) Agency for ScienceTechnology and Research(A*STAR)Singapore College of Information and Communication Engineering Dalian Minzu UniversityDalian CityLiaoning ProvinceChina Department of Environmental Health Sciences Mailman School of Public HealthColumbia UniversityNew York CityNYUSA School of Artificial Intelligence Opticsand Electronics(iOpen)Northwestern Polytechnical UniversityXi’an CityShaanxi ProvinceChina

Summary What is already known about this topic?People are likely to engage in collective behaviors online during extreme events,such as the coronavirus disease 2019(COVID-19)crisis,to express awareness,take action,and... 详细信息

关键词： collective likely extreme

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