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A Single-Site Positioning Method Based on TOA and DOA Estimation Using Virtual Stations in NLOS Environment

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China Communications 2019年第2期16卷 146-159页

作者： Rui Zhang Weiwei Xia Feng Yan lianfeng shen National Mobile Communications Research Laboratory Southeast University

This paper presents a single-site positioning method based on the joint estimation of propagation time-of-arrival(TOA) and direction-of-arrival(DOA), with the assist of virtual stations in the typical non-line-of-sight(NLOS) environment. Consider the influence of multipath noise on the positioning performance, the proposed method firstly presents a modified high-resolution estimation technique called Multipath noise Limiting Matrix Pencil(MLMP) algorithm to achieve the TOA/DOA estimations, in which the matrix pencil and matrix enhancement process are implemented to deal with the measurements from the uniform linear array(ULA) receiver. Meanwhile, the subspace dimension estimation is improved via an adaptive threshold, for enhancing the performance of high-resolution techniques in low signal-noise-ration(SNR) situation. Next the proposed method generates virtual stations utilizing the known floor plan of surrounding reflectors, and adopts a weighted Least Square(WLS) position estimator to calculate the required position, combining the TOA/DOA estimations with the location of virtual stations. Simulations are conducted to evaluate the proposed method under NLOSconditions, and the results show that comparing with the multipath fingerprinting scheme, the proposed method has better performance in various simulation scenarios.

关键词： single-site positioning TOA DOA NLOS virtual station

Performance analysis of the periodic sequence DSSS system against CW interference

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Frontiers of Electrical and Electronic Engineering in China 2008年第1期3卷 79-85页

作者： Anquan WEI lianfeng shen National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Institute of Communications Engineering PLA University of Science and TechnologyNanjing 210007China

Based on the brief account of the performance analysis result of the direct sequence spread spectrum(DSSS)system against a single tone continuous wave(CW)interference obtained from the traditional standard Gaussian approximation(SGA)hypothesis,the mathematical expression of the interference component of the symbol decision variable in the periodic sequence DSSS system under CW interference was deduced and the actual performance of the periodic sequence DSSS system against CW interference was researched through theoretical analysis and numerical *** results indicate that the interference component of the symbol decision variable in the periodic sequence DSSS system under CW interference operates at a constant level or fluctuate monochromatically,which does not approach the standard Gaussian distribution,and the actual performance of the periodic sequence DSSS system against CW interference is completely different from the analytic result resorted to the standard Gaussian approximation(SGA).The bit error performance is correlative not only with the interference-signal ratio(ISR),the frequency offset and the phase of the CW interference sensitively,but also with the individual spread spectrum code sequence.

关键词： direct sequence spread spectrum performance analysis periodic sequence CW interference standard Gaussian approximation

A NOVEL CALL ADMISSION CONTROL SCHEME IN CELLULAR/WLAN INTEGRATION AND PERFORMANCE ANALYSIS

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Journal of Electronics(China) 2009年第2期26卷 168-178页

作者： Xia Weiwei shen lianfeng National Mobile Communications Research Lab Southeast University Nanjing 210096 China

In order to achieve the Quality of Service(QoS) provisioning and efficient resource utili-zation in cellular network and Wireless Local Area Network(WLAN) integration,an Integrated Ser-vice-Based Call Admission Control(ISB-CAC) scheme is proposed in this *** integrated network is modeled by using multi-dimensional Markov *** numerical analysis is presented to evaluate the important performance measures such as the blocking probability of originating calls,the dropping probability,and the average transfer time,*** steady-state probabilities of the multi-dimensional Markov chains are obtained by using an iterative approach,and the CAC pa-rameters are optimally *** analytical model is validated by the computer *** is shown that compared with the conventional WLAN-First Call Admission Control(WF-CAC) scheme,the proposed ISB-CAC scheme not only provides better QoS for mobile users but also utilizes the bandwidth resources more efficiently.

关键词： Cellular/WLAN integration Call Admission Control(CAC) Quality of Service(QoS) Vertical handoff Markov process

Corrosion kinetics and patina evolution of galvanized steel in a simulated coastal-industrial atmosphere

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Journal of Materials Science & Technology 2019年第10期35卷 2345-2356页

作者： Chuang Qiao lianfeng shen Long Hao Xin Mu Junhua Dong Wei Ke Jing Liu Bo Liu College of Forestry Henan Agricultural UniversityZhengzhou450002China Environmental Corrosion Centre of Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Electric Power Test and Research Institute Guangzhou Power Supply Co.Ltd.(GZPS)Guangzhou510410China School of Metallurgy Northeastern UniversityShenyang110819China

The corrosion kinetics and patina(corrosion products) layer evolution of galvanized steel submitted to wet/dry cyclic corrosion test in a simulated coastal-industrial atmosphere was investigated. The results show that zinc coating has a greater corrosion rate during the initial period and a lower corrosion rate during the subsequent period, and the patina composition and structure can greatly affect the corrosion kinetics evolution of zinc coating. Moreover, Zn5(OH)6(CO3)2 and Zn4(OH)6 SO4 are identified as the main stable composition and exhibit an increasing relative amount;while Zn12(OH)15Cl3(SO4)3 cannot stably exist and diminish in the patina layer as the corrosion develops.

关键词： Zinc Galvanized steel EIS Atmospheric corrosion Patina layer

VEHICULAR NODE POSITIONING BASED ON DOPPLER-SHIFTED FREQUENCY MEASUREMENT ON HIGHWAY

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Journal of Electronics(China) 2009年第2期26卷 265-269页

作者： Xu Bo shen lianfeng Yan Feng National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China Institute of Communications Engineering Nanjing 210007 China

Vehicular node positioning needs to be quick and precise on highway for safety *** this paper,we present a novel and practical vehicular node positioning method which can achieve a higher accuracy and more reliability than the existing global-positioning-system-based po-sitioning solutions by making use of Doppler-shifted frequency measurements taken by vehicular node *** positioning method uses infrastructure nodes which are placed on the roadside every several kilometers as radiation sources to estimate the relative distances of vehicle to the infrastructure *** coordinate conversion,we get the absolute coordinates of vehicular node based on known absolute coordinates of infrastructure *** also analyze the optimal distance of neighbor infra-structure nodes in order to ensure a high *** addition,simulation results demonstrate that the accuracy of our method with Extended Kalman Filtering(EKF) is superior to the method without EKF.

关键词： Positioning Doppler-shifted frequency Vehicular Ad Hoc Network(VANET)

Study and simulation of video communications under wireless environment based on blind source separation

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Frontiers of Electrical and Electronic Engineering in China 2008年第4期3卷 418-424页

作者： Jie GUO lianfeng shen Tiecheng SONG Zhihui YE Department of Electric Engineering Hohai UniversityNanjing 210098China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China

A new scheme is proposed to separate several compressed video signals transferred in multiple wireless channels using the blind source separation *** scheme selects IEEE 802.11b and XVID compression as the wireless communications channel and MPEG-4 video compression,respectively.A simulation model is then made for the video communications under a wireless *** model can separate several video sig-nals using blind source *** show that the normalized whiten plus cyclic whiten based on cyclo-stationary(NWCW-CS)algorithm based upon the cyclo-stationary characteristics of signals has the best separation performance and fast ***,the algorithm can solve the mixing of video *** image of the transferred video signals decompressed by XVID is nearly consistent with the source *** new method meets the requirement of real-time video communications.

关键词： blind source separation cyclostationary video MPEG-4 wireless local area network

NEAR OPTIMAL CLUSTER-HEAD SELECTION FOR WIRELESS SENSOR NETWORKS

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Journal of Electronics(China) 2007年第6期24卷 721-725页

作者： Zhu Xiaorong shen lianfeng National Mobile Comm. Research Lab Southeast University Nanjing 210096 China

Clustering in wireless sensor networks is an effective way to save energy and reuse bandwidth. To our best knowledge, most of the clustering protocols proposed in literature are of a dynamic type, where cluster heads are selected in each period, followed by cluster formation. In this paper, a new static type clustering method called Hausdorff clustering, which is based on the location of sensor nodes as well as communication efficiency and network connectivity, is proposed. The cluster head, however, is rotated within the cluster by a fuzzy logic algorithtn that optimizes the network lifetime. Simulation results show that this approach can significantly increase the lifetime of the sensor network.

关键词： Sensor networks Hausdorff clustering Fuzzy logic

AUTHENTICATED SYMMETRIC-KEY ESTABLISHMENT FOR MEDICAL BODY SENSOR NETWORKS

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Journal of Electronics(China) 2007年第3期24卷 421-427页

作者： Bao Shudi Poon Carmen C.Y. shen lianfeng Zha.ng Yuanting National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China Joint Research Centre for Biomedical Engineering The Chinese University of Hong Kong N.T. Hong Kong

This study concerns security issues of the emerging Wireless Body Sensor Network (WBSN) formed by biomedical sensors worn on or implanted in the human body for mobile healthcare appli-cations. A novel authenticated symmetric-key establishment scheme is proposed for WBSN,which fully exploits the physiological features obtained by network entities via the body channel available in WBSN but not other wireless networks. The self-defined Intrinsic Shared Secret (ISS) is used to replace the pre-deployment of secrets among network entities,which thus eliminates centralized services or au-thorities essential in existing protocols,and resolves the key transport problem in the pure symmet-ric-key cryptosystem for WBSN as well. The security properties of the proposed scheme are demon-strated in terms of its attack complexity and the types of attacks it can resist. Besides,the scheme can be implemented under a light-weight way in WBSN systems. Due to the importance of the ISS concept,the analysis on using false acceptance/false rejection method to evaluate the performance of ISS for its usage in the scheme is also demonstrated.

关键词： Wireless Body Sensor Network (WBSN) Network security Authenticated key estab-lishment Physiological feature

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基于博弈论的无线传感器网络分簇路由协议

东南大学学报（自然科学版） 2010年第3期40卷 441-445页

作者：胡静沈连丰东南大学移动通信国家重点实验室南京210096

针对基于无线传感器网络的大田农业智能灌溉系统,分析了灌溉控制子网的网络拓扑结构,设计了一种分布式二级路由协议(DTTR).该协议由簇内路由和簇间路由2个部分组成,前者采用基于TDMA的星型单跳组网方式,后者采用多跳Mesh组网方式.在簇... 详细信息

针对基于无线传感器网络的大田农业智能灌溉系统,分析了灌溉控制子网的网络拓扑结构,设计了一种分布式二级路由协议(DTTR).该协议由簇内路由和簇间路由2个部分组成,前者采用基于TDMA的星型单跳组网方式,后者采用多跳Mesh组网方式.在簇间多跳路由算法中引入博弈理论,利用多阶段有限次重复博弈及基于LQI的链路质量度量方法,较好地解决了网络在多种约束下的均衡问题.分析与仿真结果表明,与常用的MintRoute协议相比,DTTR协议能在保证数据传送可靠性的基础上平衡节点能量消耗,降低由于个别节点暂时能量耗尽而导致网络阶段性失效的危险,吞吐率提高约25%,剩余能量标准差降低约30%.

关键词：无线传感器网络博弈论分簇路由协议