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Hybrid CSI-RS Transmission Mechanism-Based 3D Beamforming Scheme for FDD Massive MIMO System

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china communications 2016年第S2期13卷 109-119页

作者： Fangchao Zhang Shaohui Sun Qiubin Gao Hui Li School of Electronic and Information Engineering Beihang University state key laboratory of wireless mobile communications China Academy of Telecommunications Technology

Massive multiple-input multipleoutput(MIMO) refers to the idea that equipping base station(BS) with a large number of antenna elements,and features the ability of three dimensional(3D) beamforming technique to enable improvement in system *** prior works on massive MIMO generally rely on a common assumption of the whole channel characteristics are perfectly known at both user equipment(UE) and BS,however,this is quite difficult to realize in practical frequency division duplexing(FDD) system since the channel state information reference signal(CSIRS) overhead and CSI feedback overhead are proportional to the number of antenna *** this paper,two hybrid CSI-RS transmission mechanism-based 3D beamforming schemes are proposed in FDD massive MIMO system,in which non-beamformed CSI-RS configuration is utilized in conjunction with beamformed CSIRS *** the proposed schemes,an angle quantization-based vertical codebook and a DFT-based horizontal codebook are designed,respectively,and an eigenvalue decompositionbased precoding matrix indicator(PMI)selection algorithm is also proposed for CSI *** results show that the proposed 3D beamforming schemes achieve significant improvement in system capacity without incurring excessive CSI-RS overhead.

关键词： massive MIMO 3D beamforming CSI-RS codebook feedback PMI

A Sensor-Service Collaboration Approach for Target Tracking in wireless Camera Networks

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china communications 2017年第7期14卷 44-56页

作者： Shuai Zhao Le Yu state key laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications china mobile Information Security Center

mobile target tracking is a necessary function of some emerging application domains, such as virtual reality, smart home and intelligent healthcare. However, existing portable devices for target tracking are resource intensive and high-cost. Camera tracking is an effective location tracking way for those emerging applications which can reuse the existing ubiquitous video monitoring system. This paper proposes a dynamic community-based camera collaboration(D3C) framework for target location and tracking. The contributions of D3C mainly include that(1) nonlinear perspective projection model is selected as the camera sensing model and sequential Monte Carlo is employed to predict the target location;(2) a dynamic collaboration scheme is proposed, it is based on the local community-detection theory deriving from social network analysis. The performance of proposed approach is validated by both synthetic datasets and real-world application. The experiment results show that D3C meets the versatility, real-time and fault tolerance requirements of target tracking applications.

关键词： service collaboration camera tracking community detection sequential monte carlo

A survey of next generation mobile communications researchin china

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Chinese Science Bulletin 2011年第5期56卷 2875-2888页

作者： TIAN JinFeng 1,2 , ZHENG XiaoYing 2,3 , HU HongLin 1,2 YOU XiaoHu 1,3 1 Shanghai Research Center for wireless communications (WiCO), Shanghai 200335, china 2 Shanghai Institute of Microsystem and Information technology (SIMIT), Chinese academy of Sciences (CAS), Shanghai 200050, china 3 National mobile communications Research laboratory, Southeast University (SEU), Nanjing 210096, china Shanghai Research Center for wireless communications (WiCO) Shanghai Institute of Microsystem and Information technology (SIMIT) Chinese Academy of Sciences (CAS) National mobile communications Research laboratory Southeast University (SEU)

With the rapid development of wireless communication networks, the fourth generation (4G) has emerged to move beyond the limitations of the third generation (3G), with increased bandwidth, enhanced quality of services, and reduced costs of resources. In this paper, we discuss the key technologies of 4G and focus on surveying the ongoing research in 4G communications in china. The 4G technologies under investigation include multicarrier transmission, multiple antenna techniques, carrier aggregation, relays, cognitive radio, distributed antenna systems, network convergence, and network self-optimization. These technologies are the building blocks of 4G and contribute largely to the requirements of International mobile telecommunications Advanced (IMT-Advanced). For each technology, its benefits, research topics, and some existing approaches are examined. Finally, we briefly discuss the challenges and future research issues in 4G systems.

关键词：下一代移动通信中国无线通信网络分布式天线系统 4G系统多载波传输国际移动通信认知无线电

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Asymptotic performance of amplify-and-forward MIMO relaying with transmit antenna selection

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Science china(Information Sciences) 2010年第12期53卷 2631-2641页

作者： CAO Lei ,YANG DaCheng,YANG HongWen,FENG Chao & ZHANG Xin School of Information and Communication,beijing University of Posts and telecommunications,beijing 100876,china School of Information and Communication Beijing University of Posts and Telecommunications

This paper proposes two schemes,TAS-SD&RD and TAS-SR&RD,in which transmit antenna selection(TAS) strategies are combined with amplify-and-forward(AF) protocol in MIMO relaying scenario considering the destination has only limited channel state information(CSI) of the source-to-relay channel,and analyzes asymptotic performance of the two *** source,destination,and relay are equipped with multiple antennas,denoted by N S,N D,and N R,***,the paper derives the asymptotic outage probability and symbol error rate(SER) of the proposed schemes in the cooperative AF MIMO relaying *** analyses in high SNR regime lead to the conclusion that TAS-SD&RD and TAS-SR&RD can achieve full diversity order,N S N D + N R min{N S,N D },in some antenna configurations of the cooperative *** results that confirm our analyses are also presented in the paper.

关键词： cooperative amplify-and-forward(AF) multiple-input multiple-output(MIMO) relaying transmit antenna selection(TAS)

INTEGRATION OF OPTICAL AND wireless NETWORKS

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china communications 2014年第5期11卷 I0001-I0002页

作者：徐坤祝宁华 Hussein Mouftah the state key laboratory of Information Photonics and Optical communications at Beijing University of Posts and Telecommunications Department of Electrical and Computer Engineering University of Ottawa

For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth *** fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and ***,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated *** provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network

关键词：无线网络集成光学无线系统网络工程无线技术光纤

G-MER： Green Mobility Estimation- Based Routing Protocol in wireless Sensor Network

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china communications 2012年第5期9卷 10-21页

作者： Quan Wei Guan Jianfeng Xu Changqiao Zhang Hongke beijing Univ Posts & Telecommun State Key Lab Networking & Switching Technol Beijing 100876 Peoples R China beijing Univ Posts & Telecommun Inst Sensing Technol & Business Wuxi 214028 Peoples R China beijing Jiaotong Univ Natl Engn Lab Next Generat Internet Interconnect Beijing 100044 Peoples R China

As a core technology of Intemet of Things （loT）, wireless Sensor Network （WSN） has become a research hotspot recently. More and more WSNs are being deployed in highly mobile environments. The fast moving sensor nodes bring significant challenges for the routing decision. In this paper, we propose an efficient logical location method, and designe a mobility estimating metric and derive a novel Green Mobility Estirmtion- based Routing protocol （G-MER） for WSNs. We also set up a full framework to evaluate its per- formance. Simulation results illustrate that G-MER achieves a fairly better perforrmnce in terrm of broadcast times and link failures than AODV. What＇s more, it decreases the mean hops by about 0.25 and reduces energy consumption by about 10% during the whole experiment. All the results show that G-MER can be effectively used in fast- moving and limited resource scenarios.

关键词： IoT WSN green routing protocol rmbility estimation dynamic window energy con-suming model

mobile HTc SQUID MCG Measurement System

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Mobile HTc SQUID MCG Measurement System

2011 IEEE International Conference on Information Theory and Information Security(ICITIS 2011)

作者： Tao Wei 1) 2) Gao Jun 1) Zhang Fan 3) Cai Wenyan 4) Deng Peng 4) 1) Electronic College of Engineering Naval University of Engineering Wuhan china 2) Naval academy of Armament beijing china 3) New Star Institute of Applied technology Hefei china 4) state key laboratory for Artificial Microstructure and Mesoscopic Physics Peking University beijing china

With system integration technology,a commercial high-temperature superconducting SQUID magnetometer,a commercial Fiberglass-Reinforced Plastics （FRP） nonmagnetic liquid nitrogen container,and a commercial data acquisition system were constructed and installed on a stainless steel cart to form a simple and inexpensive mobile MCG *** this system,MCG measurements were successfully implemented in un-shield environment.

关键词： mobile HTc SQUID MCG measurement un-shield environments

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基于移动代理的入侵检测系统模型的研究

通信学报 2004年第1期25卷 22-29页

作者：王汝传王华徐小龙南京邮电学院计算机科学与技术系

阐述了基于移动代理的入侵检测系统的优势,提出了一个使用移动代理技术的入侵检测系统MAAFID。首先由数据收集代理(DCA)在网络中随机移动并收集信息,然后将收集到的信息传递给数据分析代理(DAA)来评估入侵发生的可能性。本文重点讨论了... 详细信息

阐述了基于移动代理的入侵检测系统的优势,提出了一个使用移动代理技术的入侵检测系统MAAFID。首先由数据收集代理(DCA)在网络中随机移动并收集信息,然后将收集到的信息传递给数据分析代理(DAA)来评估入侵发生的可能性。本文重点讨论了系统中数据收集代理的数目与检测出入侵发生的可能性二者之间的定量关系,最后还给出了一个仿真结果。

关键词：入侵检测移动代理网络安全 MAAFID 数据收集代理数据分析代理

基于JavaCard的移动代理安全模型研究

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通信学报 2003年第11期24卷 27-33页

作者：王汝传孙开翠杨立扬郑晓燕南京邮电学院计算机科学与技术系中国科学院研究生院信息安全国家重点实验室北京100039

欲阻止恶意主机攻击移动代理,代理中的代码信息和数据信息必须被隐藏起来。同时,还要使它们对于执行环境来说是可访问和可执行的。现有措施大都采用软件方法(如密码技术),但并不足以解决恶意主机问题。一个完全不同的方法就是使用可信... 详细信息

欲阻止恶意主机攻击移动代理,代理中的代码信息和数据信息必须被隐藏起来。同时,还要使它们对于执行环境来说是可访问和可执行的。现有措施大都采用软件方法(如密码技术),但并不足以解决恶意主机问题。一个完全不同的方法就是使用可信赖的且可抵御攻击的JavaCard来保护移动代理。本文讨论用JavaCard保护移动代理的机理,同时给出我们所设计的一个JavaCard的安全模型。

关键词：移动代理 JavaCard 安全模型