检索结果-内蒙古大学图书馆

Two-way denoise-and-forward network coding opportunistic relaying aiming at minimizing euclidean distance in multi-access phase

引用

Journal of Electronics 2011年第4期28卷 433-443页

作者： Jia, Xiangdong Yang, Longxiang Shao, Shixiang Wireless Communications Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Mathematics and Information Science Northwest Normal University Lanzhou 730070 China Nanjing University of Posts and Telecommunications Nanjing 210003 Box 188 No. 66 Xinmofan Road China

To exploit the effect of modulation schemes on the best relay selection, a novel Jointing Modulation schemes max-min criterion (JM-max-min) is proposed firstly for Two-Way De-Noise-and-Forward (DNF) Opportunistic Relaying systems (TW-DNF-OR) by aiming at minimizing the Pairwise Error Probability (PEP) of Multi-Access (MA) phase which dominates the error performance of TW-DNF-OR due to the presence of MA interference. The proposed JM-max-min criterion integrates perfectly the minimum distances of constellations and the relay links gains. Then, with the proposed JM-max-min criterion, we analyze the Symbol Error Probabilities (SEPs) of MA phase and BroadCast (BC) phase by using the approximated mathematics analysis, and present the corresponding closed-form expressions to SEPs. The numerical analysis shows, for a given modulations combination at both sources, the TW-DNF-OR systems with the proposed JM-max-min criterion outperform the one with the conventional max-min criterion. © 2011 Science Press, Institute of Electronics, CAS and Springer-Verlag Berlin Heidelberg.

关键词： Cooperative communications Max-min criterion network coding Opportunistic relaying

来源：评论

学校读者我要写书评

暂无评论

Performance analysis of data aggregation algorithms in wireless sensor networks

Performance analysis of data aggregation algorithms in wirel...

引用

International Conference on Electrical and Control Engineering (ICECE)

作者： Jian Xu Geng Yang Zheng-yu Chen Lei Chen Zhen Yang Key Laboratory of Broadband Wireless Communication & Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Nanjing University of Posts and Telecommunications Nanjing CN College of Computer Science & Technology Nanjing University of Posts and Telecommunications Nanjing Jiangsu China

Resource-constrained is a critical issue in wireless sensor networks (WSN) applications. Data aggregation (or data fusion) is one of the key techniques to solve the problem. Data aggregation can effectively reduce the data traffic, thereby reduce energy consumption, and extend the network's survival time. The research of data aggregation relates to many aspects of technology, so that the design of efficient data aggregation algorithm is a challenging task. In this paper, we investigate the effect of essential operations, scheduling algorithm and aggregation tree construction, has on data aggregation performance. The main performance such as end-to-end delay and energy-consumption of different aggregation schemes has been studied and measured by simulation experiment.

关键词： wireless sensor networks Delay Energy consumption Scheduling algorithm Algorithm design and analysis Approximation algorithms Distributed databases

来源：评论

学校读者我要写书评

暂无评论

An Expanding Ring Prediction and Location Aided AODV Routing Algorithm

An Expanding Ring Prediction and Location Aided AODV Routing...

引用

International Conference on Information technology, Computer Engineering and Management Sciences (ICM)

作者： Chunling Cheng Jingbo Hao Dengyin Zhang College of Computer Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Jiangsu Province Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Nanjing University of Posts and Telecommunications Nanjing CN

On the battlefield, the cooperative fighting and communication among combat vehicles require higher service level of real-time transmission. Combat vehicles, fast moving and the links, frequent disruption lead to the increase of packet loss rate, packet delay and routing control overhead ratio. This paper proposes an expanding ring prediction and location aided AODV routing algorithm. It improves AODV routing protocol from both routing discovery and maintenance phases. In the routing discovery phase, the algorithm limits the scope of sending RREQ through predicting the topology ring, and during the route maintenance phase, it predicts the motion range of destination node with the information provided by GPS to avoid blindness routing. The simulation results show that the proposed routing algorithm can greatly cut down the overload of combat vehicular network, improve the routing delay and reduce packet loss rate. It can meet the real-time requirements of the service transmission among combat vehicles and also improve the performance of the combat vehicular network.

关键词： Routing Vehicles Delay Prediction algorithms Routing protocols Maintenance engineering Algorithm design and analysis

来源：评论

学校读者我要写书评

暂无评论

AN IMPROVED HYBRID SEMANTIC MATCHING ALGORITHM WITH LEXICAL SIMILARITY

引用

Journal of Electronics(China) 2010年第6期27卷 838-847页

作者： Peng Rongqun Mi Zhengkun Wang Lingjiao Broadband Wireless Communication and Sensor Network Technology Key Lab of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

In this paper, we proposed an improved hybrid semantic matching algorithm combining Input/Output (I/O) semantic matching with text lexical similarity to overcome the disadvantage that the existing semantic matching algorithms were unable to distinguish those services with the same I/O by only performing I/O based service signature matching in semantic web service discovery techniques. The improved algorithm consists of two steps, the first is logic based I/O concept ontology matching, through which the candidate service set is obtained and the second is the service name matching with lexical similarity against the candidate service set, through which the final precise matching result is concluded. Using Ontology Web Language for Services (OWL-S) test collection, we tested our hybrid algorithm and compared it with OWL-S Matchmaker-X (OWLS-MX), the experimental results have shown that the proposed algorithm could pick out the most suitable advertised service corresponding to user's request from very similar ones and provide better matching precision and efficiency than OWLS-MX.

关键词： Hybrid matching algorithm Semantic matching Lexical similarity WordNet Ontology Web Language for Services (OWL-S)

来源：评论

学校读者我要写书评

暂无评论

Target moving path algorithm in wireless sensor networks

引用

Ruan Jian Xue Bao/Journal of Software 2011年第SUPPL. 1期22卷 32-39页

作者： Ma, Yin Wang, Ru-Chuan Sun, Li-Juan Huang, Hai-Ping College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

wireless sensor networks are widely used to monitor various kinds of events that happened in the sensing area. On the contrary, in order to avoid being detected, intelligent mobile targets are exerting themselves to seek paths with the least exposure passing the sensing area. Looking at the issue of intelligent moving targets seeking the appropriate moving path, the study analyzed the defects of existing moving path algorithms and proposed the AFMP (Angle First Moving Path) algorithm that generates a moving path via choosing the appropriate direction. Theoretical analysis and simulation results illustrate that the AFMP algorithm does not require global node information and isomorphic sensing radius of nodes. Also, it has a lower sensitivity when compared to the node deployment density and distribution. Therefore, the algorithm is especially suitable for the case when only local node information is known. Moreover, the complexity of the algorithm is lower than that of the Voronoi algorithm and the ideal grid algorithm. © Copyright 2011, Editorial Department of Journal of Software. All rights reserved.

关键词： Computational complexity

来源：评论

学校读者我要写书评

暂无评论

Multiuser MIMO User Selection Schemes Using Block Diagonalization

Multiuser MIMO User Selection Schemes Using Block Diagonaliz...

引用

The 2011 International Conference on Computer, communication, Control and Automation (3CA 2011)

作者： Zhang Chunfang Yang Long-xiang Ding Meiling Wu Zhihua Jiangsu Key Lab of Wireless Communications Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communications and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education China ZTE Corporation

ISBN: (纸本)9783642255403

Block diagonalization(BD)is a classical and practical interference cancelation precoding algorithm in MU-MIMO *** once BD is used,the user number can be supported simultaneously by the base station is limited by the ratio of the numbers of transmit and receive *** this paper,some existed lower complexity user selected schemes are *** schemes are all based on capacity as the performance ***,there is an inherent drawback in these *** the BS always selected the same users based on capacity or the correlation of the users in each time slot,it may not guarantee the quality-of-service of a single *** order to ensure fairness in some systems,we improve the existed algorithms and propose the round-robin user selection algorithms.

关键词： MU-MIMO,Frobenius norm,QR,user fairness,round-robin(RR),sum capacity

来源：评论

学校读者我要写书评

暂无评论

Design and Performance Testing of a FPGA Based PTP System

Design and Performance Testing of a FPGA Based PTP System

引用

International Conference on wireless communications, networking and Mobile Computing (WiCom)

作者： Wen-Nai Wang Xing-Chao Li Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education Nanjing China School of Comm. and Inform. Engg. Nanjing Univ. Posts and Telecomm. Nanjing China School of Communication and Information Engineering Nanjing University Posts and Telecommunication Nanjing China School of Comm. and Inform. Engg. Nanjing Univ. Posts and Telecomm.

IEEE 1588 specifies the precision time protocol (PTP) to synchronize independent locks with high synchronization accuracy. In this paper, PTP is implemented based on embedded FPGA board with hardware based timestamp a... 详细信息

关键词： Synchronization Hardware Field programmable gate arrays Software Protocols wireless LAN wireless networks

来源：评论

学校读者我要写书评

暂无评论

An adaptive cross-layer mechanism of multi-channel multi-interface wireless networks for real-time video streaming

An adaptive cross-layer mechanism of multi-channel multi-int...

引用

International Conference on Autonomic and Trusted Computing

作者： Liu, Jian Li, Fangmin Dou, Fei He, Xu Luo, Zhigang Xiong, Hong Hubei Key Laboratory of Broadband Wireless Communication and Sensor Network School of Information Engineering Wuhan University of Technology Wuhan China

ISBN: (纸本)9780769542720

Real-time video streaming over wireless links imposes strong demands on video codecs and quality of networks. Many measures are made to design proper routing protocols and channel assignments (CAs) for multi-channel multi-interface (MCMI) wireless networks, since it can provide higher performance than single channel. However, there still has not been a well-studied proposal to guarantee real-time video quality in this situation. Hence, it motivates us to explore the potential synergies of exchanging information between different layers to support real-time video streaming over MCMI wireless networks. In this article we jointly consider three layers of the protocol stack: the application, data link and physical layers, and propose an adaptive cross-layer mechanism for real-time video streaming (ACMRV) used in this scenario, which includes both an efficient CA and an adaptive FEC mechanism. We analyze the performance of the proposed architecture and extensively evaluate it via NS-2. The results show that the real-time video quality can be greatly improved by our proposal. © 2010 IEEE.

关键词： Video streaming

来源：评论

学校读者我要写书评

暂无评论

QoS-guaranteed cross-layer resource allocation algorithm for multiclass services in downlink LTE system

QoS-guaranteed cross-layer resource allocation algorithm for...

引用

2010 International Conference on wireless communications and Signal Processing, WCSP 2010

作者： Ai, Qing Wang, Ping Liu, Fuqiang Wang, Yujin Yang, Feifei Xu, Jing Broadband Wireless Communication and Multimedia Laboratory Tongji University Shanghai China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Road Shanghai 200050 China Shanghai Research Center for Wireless Communications Information Building 280 Linhong Road Shanghai 200335 China

ISBN: (纸本)9781424475551

In this paper, a QoS-guaranteed cross-layer resource allocation algorithm for multiclass services in downlink LTE system is proposed, which takes EXP rule, channel quality variance, real-time services and non-real-time services and minimum transmission rate into account. The key features of the proposed algorithm are that all the users and resource blocks will be allocated step by step respectively. Numerical results demonstrate that the proposed algorithm effectively guarantees the user QoS requirement for multiclass services. At the same time, it mainly maintains the throughput and fairness performances in a high level. ©2010 IEEE.

关键词： Quality of service

来源：评论

学校读者我要写书评

暂无评论

An Adaptive Cross-Layer Mechanism of Multi-channel Multi-interface wireless networks for Real-Time Video Streaming

An Adaptive Cross-Layer Mechanism of Multi-channel Multi-int...

引用

Symposia and Workshops on Ubiquitous, Autonomic and Trusted Computing, UIC-ATC

作者： Jian Liu Fangmin Li Fei Dou Xu He Zhigang Luo Hong Xiong Hubei Key Laboratory of Broadband Wireless Communication and Sensor Network& School of Information Engineering Wuhan University of Technology Wuhan China

关键词： Streaming media wireless networks Forward error correction Delay Real time systems Throughput Switches

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：