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An efficient coverage control algorithm for three-dimensional underwater sensor networks

Advances in Information Sciences and Service Sciences 2012年第10期4卷 393-399页

作者： Xiao, Fu Yang, Yang Sun, Li Wang, Ruchuan Nanjing University of Posts and Telecommunications Nanjing 210003 China Provincial Key Laboratory for Computer Information Processing Technology Soochow University Suzhou 215006 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing 210003 China

Strategy of sensor nodes deployment is directly related to the cost and performance for underwater wireless sensor networks, which is largely determined the various service-quality improvement of wireless sensor networks. In order to improve the coverage of the target area, this paper presents a distributed algorithm of coverage control. Assume that nodes initially deployed on the surface of the water and can only move in vertical direction in 3-D space, the algorithm is first to control the nodes in-depth and relocate the nodes at different depths, then the nodes continue to adjust their depths until there is no augment for improving their coverage, and to achieve efficient coverage of the three-dimensional sensor networks ultimately. Experimental results show that compared with traditional random deployment method, the proposed coverage control algorithm can improve coverage of network effectively.

关键词： Quality control

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Dynamic configuration of physical carrier sensing threshold and throughput analysis

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Journal of Computational Information Systems 2012年第11期8卷 4561-4568页

作者： Ran, Wenwen Zhu, Qi Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab. on Wideband Wireless Communications and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

The choice of physical carrier sensing threshold affects the performance of the MAC layer protocol in multi-hop networks. This paper takes the effect of carrier sensing threshold on QoS into account, and develop an analytical model to dynamically achieve the carrier sensing threshold and analyse the impact on QoS. On the occasion of path loss only (a = 4), the paper proposes a method to get CST, which is to tradeoff the areas of hidden and exposed nodes, in other words, the numbers of both can reach compromise and the total number is least. In this way, we can get CST of every node that makes spatial reuse and throughput achieve balanced. It is found that the ratio of CST to the distance of sender and receiver has important effect on system throughput. At last, the paper compares the performance of the proposed method to that one of [1], and finds that this method improves the system throughput and spatial reuse. © 2012 Binary Information Press.

关键词： Packet loss

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Differential space-time block coding based cooperative spectrum sensing over fading environments in cognitive radio sensor networks

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Journal of Information and Computational Science 2012年第15期9卷 4599-4606页

作者： Chen, Zhi Yue, Wenjing College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

Incorporating cognitive radio capability in recource-constrainted multihop wireless sensor networks may help realize the deployment of multiple overlaid sensor networks, and eliminate collision and excessive contention delay incurred by dense node deployment. One of the main requirements of cognitive radio sensor networks is the ability to detect the presence of the primary user with fast speed and high accuracy in wireless environments. Cooperative spectrum sensing emerges as a promising candidate to meet these requirements. In practice, however, since the local sensing observations are forwarded to a sink through fading channels, the sensing performance of cooperative spectrum sensing is deteriorated due to the reporting errors introduced by the fading channels. To deal with this limitation, we propose a differential space-time block coding based cooperative spectrum sensing scheme to improve the sensing performance by decreasing the probability of reporting error. The sensing performance is also derived. Numerical results verify that better sensing performance can be achieved in proposed scheme compared to the conventional cooperative spectrum sensing. © 2012 by Binary Information Press.

关键词： Cognitive radio

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Decentralized waveform design for MIMO cognitive radio under interference temperature constraint

Decentralized waveform design for MIMO cognitive radio under...

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2nd International Conference on networking and Distributed Computing, ICNDC 2011

作者： Wei, Fei Xia, Pengrui Yang, Zhen Tian, Feng Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing Jiangsu Province China

ISBN: (纸本)9780769544274

This paper addresses the information rate maximization problem under interference temperature constraint for a multiple-in multiple-out cognitive radio (MIMO-CR) network in which each CR user is equipped with multiple antennas. We formulate this as a Nash equilibrium problem where each CR tries to maximize its own utility by choosing appropriate wave-form. A decentralized iterative water-filling algorithm (IWFA) with pricing is proposed to solve it;the pricing mechanism is used to satisfy the interference temperature constraint while achieving the Nash equilibrium. Simulation results show that our algorithm can satisfy the interference temperature constraint perfectly and is fast convergent;we also show that the proposed IWFA with pricing can achieve a performance improvement in terms of sum-rate over the existed IWFA with power shaping. © 2011 IEEE.

关键词： Costs

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An expanding ring prediction and location aided AODV routing algorithm

An expanding ring prediction and location aided AODV routing...

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2011 International Conference on Information technology, Computer Engineering and Management Sciences, ICM 2011

作者： Cheng, Chunling Hao, Jingbo Zhang, Dengyin College of Computer Nanjing University of Posts and Telecommunications Nanjing Jiangsu 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing Jiangsu 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Jiangsu Province Nanjing Jiangsu 210003 China

ISBN: (纸本)9780769545226

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 rouing 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. © 2011 IEEE.

关键词： Forecasting

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Multiuser MIMO user selection schemes using block diagonalization

Multiuser MIMO user selection schemes using block diagonaliz...

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2011 International Conference on Computer, Communication, Control and Automation, 3CA 2011

作者： Chunfang, Zhang Long-Xiang, Yang Meiling, Ding Zhihua, Wu Jiangsu Key Lab. of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab. of Broadband Wireless Communications and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China ZTE Corporation China

ISBN: (纸本)9783642255403

Block diagonalization (BD) is a classical and practical interference cancelation precoding algorithm in MU-MIMO system. But 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 antennas. In this paper, some existed lower complexity user selected schemes are discussed. These schemes are all based on capacity as the performance measure. However, there is an inherent drawback in these algorithms. Since 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 user. In order to ensure fairness in some systems, we improve the existed algorithms and propose the round-robin user selection algorithms. © 2011 Springer-Verlag.

关键词： MIMO systems

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A symbol-joint resource allocation for OFDM systems with asymptotical fairness

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Journal of Information and Computational Science 2011年第12期8卷 2385-2393页

作者： Lv, Linshu Zhu, Qi Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab. on Wideband Wireless Communications and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

In general, the Marginal Adaptive (MA) algorithms are supposed to be fairness-oriented and the absolute fairness among users can be guaranteed in one symbol duration. In fact, the system performance is insensibly sacrificed to achieve such instantaneous fairness, which seems not very necessary or essential in practice for most applications. Instead, it is enough for users to get the same data rate after a period of a couple of symbols. This paper presents an asymptotically fair allocation algorithm named the Symbol- Joint Resource Allocation (J-SRA) based on the MA. It greatly exploits the time diversity by optimizing the subcarrier and power allocation for the successive N symbols in time-frequency two-dimensional domain. The simulation results show that the proposed scheme achieve a better performance than the original one. 1548-7741/Copyright © 2011 Binary Information Press.

关键词： Orthogonal frequency division multiplexing

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The wireless sensor network localization algorithm based on improved pattern genetic algorithm

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Journal of Computational Information Systems 2011年第9期7卷 3031-3038页

作者： Huang, Haiping Cai, Qiwang Wang, Ruchuan She, Baoyang Ma, Yujing 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 Lab. of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Localization is one of the important technical issues of wireless sensor networks. Based on the traditional genetic algorithm applied in node localization, this paper introduces pattern search algorithm for the selection of population, meanwhile, genetic operators are designed. The theoretical analysis and simulation results show that, even though the proportion of anchor nodes and network connectivity is poor, and distance measurements are corrupted by Gaussian noise, the improved algorithm achieves high accuracy. Thus, it can be applied to most large-scale wireless sensor networks for node localization. © 2005 by Binary Information Press.

关键词： Genetic algorithms

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