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THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR SIDELOBE SUPPRESSION IN MB-OFDM COGNITIVE RADIOS

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THE RELATIONSHIPS AMONG DATA SYMBOLS SATISFIED FOR SIDELOBE ...

On degrees of freedom of the cellular network

2009 IEEE International Conference on communication technology and Applications（ICCTA2009）

作者： Zhigang Xu Cheng Yang Weixia Zou Zheng Zhou key lab of Universal wireless communications MOE wireless network lab Beijing University of Posts and Telecommunications Beijing 100876 china

＜正＞From the mathematic expression,we can see that sidelobe power of multi-band orthogonal frequency-division multiplexing（MB-OFDM） signal is a function of the data symbols loaded on the *** the derivation of the minimum of the function,relationships among data symbols, which help to suppress sidelobes,are *** types of methods,referred as Sub-carrier Adding（SA） method and Sub-carrier Multiplying（SM） method, are proposed,which realize the relationships at the cost of small degradation in information transmission *** a result,with the proposed methods,the sidelobe power can be *** results also prove this.

关键词： OFDM sidelobe suppression data symbols relationships

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Science china(Information Sciences) 2010年第05期53卷 1034-1043页

作者： SUN Jun 1,2 , LIU YingZhuang 1,2 & ZHU GuangXi 1,2 1 Department of Electronics and Information Engineering, Huazhong University of Science and technology, Wuhan 430074, china 2 Division of Optical network and Intelligent communication, Wuhan National laboratory for Optoelectronics, Wuhan 430074, china 1. Department of Electronics and Information Engineering Huazhong University of Science and Technology Wuhan 430074 China2. Division of Optical Network and Intelligent Communication Wuhan National Laboratory for Optoelectronics Wuhan 430074 China

In this paper, we consider the capacity limits of the cellular network by modeling it as consisting of two mutually interfering multiple access channels with multiple antennas at each receiver (e.g., base station). By developing a tight outerbound as well as an achievable scheme which exploits the idea of interference alignment, we are able to exactly characterize the sum degrees of freedom (DoF) of the network when the channel coefficients are timeor frequency-varying, which equals KM K+min(M,K) (where M and K denote the number of receiver antennas and number of users in per cell, respectively) per cell. From the DoF result, it can be observed that in addition to the multi-user gain which has been reported for the network with single-antenna BSs, there also exists the multi-antenna gain in the cellular network. In particular, when the number of users is large, we can nearly achieve the interference-free DoF of a cellular network with multiple-antenna BSs, which is a somewhat surprising result.

关键词： capacity degrees of freedom cellular network interference alignment interference channel MIMO

Optimal power allocation for cognitive relay networks: amplify-and-forward versus selection relay

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Science china(Information Sciences) 2011年第4期54卷 861-872页

作者： YUE WenJing 1,2,ZHENG BaoYu 1,2,MENG QingMin 1,YUE WenJie 3 & CUI JingWu 1 1 Institute of Signal Processing and Transmission,nanjing University of Posts and Telecommunications,nanjing 210003,china 2 Department of Electronic Engineering,Shanghai Jiaotong University,Shanghai 200240,china 3 Shanxi Institute of educational Science,Taiyuan 030009,china 1. Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China2. Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China3. Shanxi Institute of Educational Science Taiyuan 030009 China

We consider a cognitive relay network which is defined by a source,a destination,and cognitive relay nodes and primary user *** this network,a source is assisted by cognitive relay nodes which allow coexisting with primary user nodes by imposing severe constraints on the transmission power so that they operate below the noise floor of primary user *** this paper,we mainly study the power allocation strategies of this system to minimize the outage probability subject to total and individual power constraints for cognitive relay nodes and subject to interference constraints for primary user nodes.A relay transmission scheme,namely amplify-and-forward (AF),is *** first present an optimal power allocation (OPA) scheme to minimize the system outage probability,based on instantaneous channel state information among the source,destination and relay nodes and mean channel gains between primary user nodes and cognitive ***,we propose a selection AF scheme (S-AF) where the single best relay is chosen to assist in the transmission and study power allocation strategy for S-AF to minimize outage *** analytical power allocation strategies have been validated through numerical *** results indicate that the AF with OPA and S-AF with OPA have significantly better outage behavior and average throughput than AF and S-AF schemes *** also find that S-AF with OPA achieves a higher throughput,and hence lower outage probability than AF with OPA.

关键词： cognitive radio (CR) relay networks power allocation outage probability

Residual Energy and Header Cost based Time Diversity Clustering for WSN

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Residual Energy and Header Cost based Time Diversity Cluster...

2006 10th International Conference on communication technology（ICCT 2006）

作者： Tao Zhong Sheng Wang Shizhong Xu key lab of Optical communication School of communication and Information Engineering University of Electronic Science and technology of china Chengdu P. R. china

Recently wireless sensor networks （WSN） have received a lot of attention due to their wide applications both in military and civil fields. Generally sensors in such systems are small devices with limited on-board energy supply, thus efficient management of the network is crucial in extending the life of the system. In this paper we present a novel energyaware approach for clustering nodes in wireless sensor network. The main goal of our approach is to design a clustering algorithm which could guarantee fairly uniform and optimum cluster distribution, convergence in an acceptable time while incurring low overhead.

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一种容忍攻击的传感器网络节点定位算法

武汉理工大学学报 2008年第7期30卷 111-115页

作者：叶阿勇马建峰西安电子科技大学计算机网络与信息安全教育部重点实验室

针对无线传感器网络中定位系统存在脆弱性的问题,提出一种容忍攻击的安全定位算法AtLoc。以方差的无偏估计为安全性检验依据,采用随机方法找出一个最小安全参照集,在此基础上,利用基于最小安全参照集的预测残差为依据逐个检查剩余参照... 详细信息

针对无线传感器网络中定位系统存在脆弱性的问题,提出一种容忍攻击的安全定位算法AtLoc。以方差的无偏估计为安全性检验依据,采用随机方法找出一个最小安全参照集,在此基础上,利用基于最小安全参照集的预测残差为依据逐个检查剩余参照点是否异常,从而提高了定位系统容忍攻击的能力。对AtLoc算法进行了理论分析,并通过模拟实验验证了其容忍攻击的能力。

关键词：无线传感器网络安全定位

Dynamic Coverage with wireless sensor and Actor networks in Underwater Environment

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IEEE/CAA Journal of Automatica Sinica 2015年第3期2卷 274-281页

作者： Xiaoyuan Luo Liu Feng Jing Yan Xinping Guan the Institute of Electrical Engineering Yanshan University the Department of Automation Shanghai Jiao Tong Universityand Key Laboratory of System Control and Information ProcessingMinistry of Education of China

This paper studies the problem of dynamic coverage with wireless sensor and actor networks (WSANs) in underwater environment. Different from most existing works, the WSANs consist of two kinds of nodes, i.e., sensor nodes (SNs) which cannot move autonomously and actor nodes (ANs) which can move autonomously according to the performance requirement. The problem of how to coordinate two kinds of nodes to facilitate dynamic coverage in underwater environment is challenging due to their heterogeneous capabilities. To reduce redundancy of communication links and improve connectivity between ANs and SNs in underwater WSANs, a min-weighted rigid graph based topology optimization scheme is first developed, such that the underwater communication energy consumption can be saved. With the optimized topology, a dynamic coverage strategy is proposed to improve the coverage among SNs and ANs for underwater WSAN where underwater fluid motions are considered. Furthermore, it is proved that the network coverage area is connected by using the min-weighted rigid graph. Finally, simulation results are presented to show the effectiveness of the main results. © 2014 Chinese Association of Automation.

关键词： Energy utilization Graphic methods sensor nodes Topology

MOBILITY AIDED LOCALIZATION OF wireless sensor networkS WITH INACCURATE RANGE MEASUREMENTS

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Journal of Electronics(china) 2006年第3期23卷 413-416页

作者： Sun Guolin Guo Wei National key lab of communication UESTC Chengdu 610054 China

This paper studies the relationship between mobility, navigation and localization in the context of wireless sensor networks with mobile beacons. It is observed that mobility can aid in network node localization and that once localized, the network nodes can localize and track a mobile object and guide its navigation. A distributed kernel-based algorithm is proposed that enables the nodes to establish confident position estimates in the presence of ranging inaccuracies. The proposed approach features robustness with respect to range measurement inaccuracies, low complexity and distributed implementation, using only local information. Simulation validates our approach viable.

关键词： wireless sensor network Localization Range inaccuracy

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

A Power Line-delivered and Lamp-based Broadband Mobile communication System

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ZTE communications 2007年第3期5卷 28-31页

作者： Tang Youxi Shao Shihai (National key lab of communications,UESTC,Chengdu 610054,china)

A new mobile communications network architecture is proposed to solve four existing bottlenecks that restrict the rapid development of mobile communications,as well as to meet the development demands of future broadband mobile communications. The architecture introduces the Information Lamp (IL),a novel device carrying out transceiver function,as the access point,besides providing light. It fulfills information interaction between the access points and radio access network through the power line (or fiber). The new system,supported by core technologies such as multi-antenna based distributed space-time signal processing and distributed radio resource management,integrates the wired and wireless networks to provide high-speed and high-quality mobile communication services.

关键词： MIMO line A Power Line-delivered and Lamp-based Broadband Mobile communication System Access