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International Conference on network Computing and Information Security

作者： Jian, Zhang Qi, Zhu Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing China

ISBN: (纸本)9780769543550

Cognitive radio(CR) is a concept to improve the utilization of scarce spectrum resources in wireless communication, and orthogonal frequency division multiplexing (OFDM) is regarded as the best technology to match with the CR systems. In this paper, a new adaptive resource allocation algorithm for OFDM CR systems is presented. This algorithm solves the optimization problem based on maximize the total transmit bit rates of secondary users, on the one hand, the total transmit power of secondary users should below the transmit power constraint, on the other hand, the interference to primary users should under the maximum interference level, then allocate sub channels by an improved Hungarian Algorithm, and load bits and power by greedy algorithm. Simulation results show that the proposed algorithm can improve the system throughput comparing with some other sub optimal algorithms. © 2011 IEEE.

关键词： Cognitive radio

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BIPR: A new TCP variant over satellite networks

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Journal of China Universities of Posts and Telecommunications 2011年第SUPPL. 1期18卷 34-39页

作者： Xiao, Fu Sun, Li-Juan Wang, Ru-Chuan Fang, Yue-Chao College of Computer Science and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 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 Nanjing 210003 China

Standard TCP perform poorly in satellite networks since the long delay, high bit error ratio and other characters. A new TCP variant, called BIPR for satellite networks is presented in this paper. Using the binary increase of window growth function, long bandwidth-delay product can be overcome, while probe method is also adopted in BIPR for conquer the high bit error rates in satellite links. Simulation results show that good performances in terms of throughput, link utilization and RTT fairness can be achieved in satellite networks using our method. © 2011 The Journal of China Universities of Posts and Telecommunications.

关键词： Satellites

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Detecting selective forwarding attacks in WSNs using watermark

Detecting selective forwarding attacks in WSNs using waterma...

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2011 International Conference on wireless communications and Signal Processing, WCSP 2011

作者： Zhang, Deng-Yin Xu, Chao Siyuan, Lin Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

ISBN: (纸本)9781457710100

This paper studies the selective forwarding attacks in wireless sensor networks (WSNs) and proposes a method to detect selective forwarding attacks based on digital watermarking technology. This method embeds watermark into the source data packets, which will be extracted at the base station (BS). The BS will judge whether there are malicious nodes in the transmission path by analyzing the packet loss rate from received data. Simulation results show that this method can effectively detect whether malicious nodes have discarded or tampered the contents of the packets. © 2011 IEEE.

关键词： Digital watermarking

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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 improved game-theoretic spectrum sharing in cognitive radio systems

An improved game-theoretic spectrum sharing in cognitive rad...

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International Conference on communications and Mobile Computing

作者： Ma, Liang Zhu, Qi Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (纸本)9780769543574

In this paper, an improved game-theoretic spectrum sharing algorithm is proposed. Besides considering the available bandwidth, a reliance factor that represents how the primary users would like to lease the free spectrum to secondary users is introduced and the battery capacity of secondary users is taken into account. The simulation results show that the shared spectrum is in direct proportion to the reliance and battery capacity. The existence and uniqueness of Nash equilibrium are proved. © 2011 IEEE.

关键词： Cognitive radio

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The controlled-worm system designwork

The controlled-worm system designwork

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

作者： Zhang, Dengyin Li, Dacheng Wang, Ye Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

ISBN: (纸本)9780769545226

In order to solve the controllability problem of worm attack range and effect in network counterwork and achieve the precise attack on the target host, we propose a propagation control method based on lifetime and a damage control method based on atomic attack. Based on these, we design a kind of CWS (controlled-worm system) and implement the prototype system in the LAN. Implementation results show that CWS can not only control the survival time but also carry out targeted attacks on controlled hosts. Comparing with traditional controlled worms, the worm controlled by the CWS can attack targeted hosts with a certain degree of covertness and pertinence. © 2011 IEEE.

关键词： Atomic attack Attack control Controlled worm Propagation control survival time hosts

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A multi-path transmission algorithm for Layered scalable coding

A multi-path transmission algorithm for Layered scalable cod...

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2011 International Conference on wireless communications and Signal Processing, WCSP 2011

作者： Zhang, Deng-Yin Wen, Jun Siyuan, Lin Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

ISBN: (纸本)9781457710100

wireless Multimedia sensor network (WMSN) need to transfer large amounts of video streaming data, how to achieve efficient and reliable transmission becomes a research hotspot. Layered scalable coding techniques can reduce the amount of data to improve channel efficiency. The multi-path transmission technology can balance the network load to fully utilize network resources. This paper presents a multi-path transmission algorithm for Layered scalable coding. First, the source node divides the video source sequence into base layer and enhancement layers through scalable video coding. Second, the energy delay gradient and delay gradient are set up for each sensor node. Last, multiple paths with different service quality are set up according to node gradient, so that it can adapt to the transmission needs of different stream layers. Simulation results show that the algorithm has good bandwidth adaptation and can better meet the business requirements of different users. ©2011 IEEE.

关键词： Scalable video coding

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A handoff control algorithm based on services-priority and channel reservation

A handoff control algorithm based on services-priority and c...

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

作者： Zhang, Deng-Yin Cui, Lei Tong, Zhen-Yan Key Lab. of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

ISBN: (纸本)9780769545226

For some existing handoff control algorithms in Aerospace Information network, the success rate of their handoff calls is not high. This paper proposes a handoff control algorithm based on service priorities and channel reservation. The services are divided into different priorities, and reserve different number of channels for different businesses according to their priorities. Besides, the algorithm allows the emergency services to seize the channel resources. Simulation results show that when comparing with the traditional handoff algorithms, the algorithm we proposed can reduce the handoff failure rate. And ensure the handoff performance of emergency users. © 2011 IEEE.

关键词： Emergency services

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A camera self-calibration method based on dual constraints of multi-view images

A camera self-calibration method based on dual constraints o...

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2011 International Conference on wireless communications and Signal Processing, WCSP 2011

作者： Liu, Feng Han, Weiwei Xu, Qiong Lin, Qiongjie Fan, Jingjing Image Processing and Image Communication Jiangsu Key Laboratory Nanjing China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China

ISBN: (纸本)9781457710100

Camera calibration is the essential step of obtaining 3D information from 2D views in the field of computer vision, which is widely used in the area of 3D reconstruction, navigation, visual supervision, etc. A camera self-calibration method based on dual constraints of multi-view images is proposed to make calibration possible when there is no reference calibration block or the movement of camera is arbitrary. In this method, multi-view images are preprocessed first to select three images which are most suitable for camera self-calibration, then we use the method based on the genetic algorithm, the camera parameters are finally estimated by using epipolar geometry matching error and reprojection error as fitness functions as two steps. Experimental results show that the proposed camera self-calibration method is correct and effective. © 2011 IEEE.

关键词： Genetic algorithms

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Joint design of physical layer network coding and channel decoding based on trellis coded modulation in two-way relay channel

Joint design of physical layer network coding and channel de...

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2011 International Conference on wireless communications and Signal Processing, WCSP 2011

作者： Chen, Zhi-Cheng Zheng, Bao-Yu Ji, Xiao-Dong Zhang, Wei-Liang Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing 210003 China

ISBN: (纸本)9781457710100

In this paper we consider a two-way relaying system, where two users A and B wish to exchange information with the help of a common relay R., To decode the superimposed signal from A and B efficiently, we propose a new scheme of jointing physical layer network coding (PNC) and channel decoding for multiple-access channel based on trellis coded modulation (TCM). Since TCM combines channel coding with modulation, the scheme improves the free distance of the coding sequence, thus more encoding gain is achieved. In addition, taking advantage of the linearity of convolutional code and MAC-XOR NC code, the digital bits of network coding are estimated directly. In a word, we propose a novel scheme which considers channel coding, modulation and PNC at the same time, so that not only the information transmission rate is increased, but also the reliability is improved. © 2011 IEEE.

关键词： Channel coding

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