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International Conference on wireless communications and Signal Processing

作者： Yidan Zhuang Su Zhao Xiaorong Zhu Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education (Nanjing University of Posts & Telecommunications)

ISBN: (纸本)9781467358309

Femtocell networks which use femtocell access point (FAP) and existing networks as backhaul connectivity can meet the requirement of high data rate for wireless communication system as well as solve the indoor coverage problem. The handover from femtocell to femtocell is quite demanding and complicated because there are hundreds of possible target FAPs when mobile station (MS) moves out from the coverage of its serving FAP. In this paper, we propose a new mechanism for femtocell-to-femtocell handover which considers several factors such as received signal level, the hidden FAP problem and the access mode of femtocell. The simulation results show that our proposed scheme has a lower handover failure rate and a smaller neighbor femtocell list than the traditional scheme which is based on received signal level only.

关键词： handover femtocell received signal strength indicator femtocell access point

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Gossip-Based Indexing Ring Topology for 2-Dimension Spatial Data in Overlay networks

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Procedia Engineering 2012年 29卷 3727-3731页

作者： Z.Q. Zou Y. Wang B. Hu R.C. Wang College of Computer Nanjing University of Posts and TelecommunicationsNanjing 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 (Nanjing University of Posts and Telecommunications) Ministry of Education Jiangsu Province Nanjing Jiangsu 210003 China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210046 China

Overlay networks are used widely in the Internet, such as retrieval and share of files, multimedia games and so on. However, in distributed system, the retrieval and share of 2-dimension spatial data still have some difficult problems and can not solve the complex retrieval of 2-dimension spatial data efficiently. This article presents a new indexing overlay networks, named 2D-Ring, which is the ring topology based on gossip for 2-dimension spatial data. The peers in our overlay networks exchange the information periodically and update each local view by constructing algorithm. 2-dimension spatial data is divided by quad-tree and mapped into control points, which are hashed into 2D-Ring by SHA-1 hash function. In such way, the problem of 2-dimension spatial data indexing is converted to the problem of searching peers in the 2D-Ring. A large of extensive experiments show that the time complexity of constructing algorithm of 2D-Ring can reach convergence logarithmically as a function of the network size and hold higher hit rate and lower query delay.

关键词： Overlay networks 2-Dimension Spatial Data Indexing Gossip

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Resource Allocation Scheme for Device-to-Device communication Underlying LTE Downlink network

Resource Allocation Scheme for Device-to-Device Communicatio...

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International Conference on wireless communications and Signal Processing

作者： Ran An Jun Sun Su Zhao Shixiang Shao Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education (Nanjing University of Posts & Telecommunications)

ISBN: (纸本)9781467358309

Future cellular networks such as IMT-Advanced are expected to allow Device-to-Device (D2D) communication as an underlay. During the downlink period, both of the D2D receiver and cellular user will suffer from interference caused by radio resource sharing. In this paper, a joint resource allocation and resource reuse scheme is investigated, in which resource allocation to cellular users is employed on proportional fair algorithm and resource reuse to D2D users is employed on a greedy heuristic algorithm. The greedy heuristic algorithm determines the D2D mode is appropriate or not by path loss comparison, then decreases the interference to cellular user by selection of the minimum channel gain between cellular user and D2D transmitter each time. System simulations in two different scenarios demonstrate that sum throughput of cellular user and D2D pair is improved using the proposed scheme, and the interference to cellular user is under control.

关键词： Device-to-Device resource allocation mode selection resource reuse interference control

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An out-of-order data streams oriented BP algorithm for association rules of big data

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Xitong Gongcheng Lilun yu Shijian/System Engineering Theory and Practice 2014年 34卷 158-164页

作者： Zhuo, Lin-Chao Wang, Kun The MOE Key Lab of Broadband Wireless Communication and Sensor Network Nanjing University of Posts and Telecommunications Nanjing210003 China

Because of the difficulty of getting the association rules over out-of-order streams for big data, this paper presents an improved BP algorithm based on dynamical adjustment. In this algorithm, a dynamic adaptive structural is settled according to environmental requirements, which can automatically remove invalid training neurons, and optimize the iterative training process. Furthermore, the algorithm dynamically adjusts three factors (i.e. momentum factor, right learning index and threshold learning factor) during the learning process to speed up the response time and enhance the stability of the network. In the simulation, three factors are changed by a self-adapting adjusting mechanism. By comparing with the traditional BP algorithm, it gets more convergence times and convergence rate. Results also indicate that the proposed algorithm can obviously improve efficiency and finally obtain the association rules over out-of-order data streams.

关键词： Big data

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Efficient passive measurement-device-independent quantum key distribution

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Physical Review A 2019年第5期99卷 052325-052325页

作者： Chun-Hui Zhang Chun-Mei Zhang Qin Wang Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Broadband Wireless Communication and Sensor Network Technology Key Laboratory of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China Telecommunication and Networks National Engineering Research Center Nanjing University of Posts and Telecommunications Nanjing 210003 China

To date, only active-decoy-state methods have been adopted in current measurement-device-independent (MDI) quantum key distribution (QKD) protocols, causing security loopholes when modulating multiple light intensities with practical devices. To solve this problem, the passive-decoy-state method will be a good choice. Until today practical passive-decoy-state MDI QKD is still missing. In this paper, based on a recently discussed structure of heralded single-photon sources, we propose a passive-decoy-state MDI QKD protocol. In present work, one does not need to modulate light sources into different intensities, but utilizes the built-in local detection events to passively generate different decoy states. Furthermore, through carrying out an appropriate mathematical method, we are able to give very precise estimations for single-photon-pair contributions. As a result, our protocol can exhibit distinct advantages compared with state-of-the-art MDI QKD schemes even when the finite-key-size effect is taken into account. Therefore, our protocol seems a promising candidate to enhance both the security and performance of MDI QKD in practical implementation.

关键词： Quantum cryptography

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IOT platform-oriented Socket design and optimization

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Jilin Daxue Xuebao (Gongxueban)/Journal of Jilin University (Engineering and technology Edition) 2012年第SUPPL. 1期42卷 290-294页

作者： Wang, Kun Yu, Yue Zhang, Yu-Hua Guo, Huang Wang, Lin-Lin Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

An efficient design for a Socket server with buffer pool and a thread pool for concurrent request on the IOT platform is presented. This reduces the system overhead and buffer usage to the largest extent while faced with a large number of connections and digital requests. The simulation results show that a Socket server with a thread pool and buffer pool could lower the overhead on the context switch of threads as well as the I/O blocking.

关键词： Lakes

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Poster: Secret key generation from CFR for OFDM TDD systems over fading channels

Poster: Secret key generation from CFR for OFDM TDD systems ...

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International Conference on communications and networking in China (CHINACOM)

作者： Yuexing Peng George C. Alexandropoulos Peng Wang Yonghui Li Dac-Binh Ha Key Lab of Universal Wireless Communication Beijing University of Posts and Telecommunications Beijing China Broadband Wireless and Sensor Network Group Athens Information Technology Peania Greece Centre of Excellence in Telecommunications University of Sydney Sydney Australia Institute of Research and Development Duy Tan University Danang Vietnam

One of the basic problems in cryptography is the generation of a common secret key between two legitimate parties in order to prevent eavesdropping. In this paper, we develop an information-theoretic secret key generation method that exploits the physical layer properties of the multipath channel in orthogonal frequency division multiplexing (OFDM) systems with time division duplexing (TDD), and in particular the amplitude and phase of the estimated channel frequency response (CFR). Both the fast space decorrelation and the independency of the amplitude and phase of the multipath fading channel are used to generate the secret key, leading to increased secrecy bit rate and negligible secrecy leakage. The effect of the channel estimation error, delay and mobility are investigated for the presented method. Simulation results corroborate the increased performance of the proposed method over existing ones.

关键词： wireless communication Security OFDM Fading communication system security Indexes Channel estimation

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Bacterial foraging optimization algorithm based routing strategy for wireless sensor networks

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International Review on Computers and Software 2012年第6期7卷 2826-2830页

作者： Chen, Zhi Li, Shuai Yue, Wenjing Hu, Luoquan Sun, Wanxin College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing 210003 China Suzhou Entry-Exit Inspection and Quarantine Bureau Suzhou 215104 China

In order to improve energy efficiency, the bacterial foraging optimization algorithm (OBFOA) is applied into the routing strategy for wireless sensor networks. The proposed strategy makes proper improvements on bacteria's foraging operation to improve the performance of the algorithm, such as the adaptive step strategy in the swimming operation and the comprehensive selection mechanism in the tumbling operation. OBFOA builds optimized data transfer paths in wireless sensor networks through the processes of chemotaxis, global quorum sensing mechanisms, reproduction and elimination-dispersal. Simulation results show that the proposed strategy can balance the energy consumption of nodes effectively and prolong the overall network lifetime. © 2012 Praise Worthy Prize S.r.l. - All rights reserved.

关键词： wireless sensor networks

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Approaching the ideal quantum key distribution with two-intensity decoy states

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Physical Review A 2015年第2期92卷 022332-022332页

作者： Chun-Hui Zhang Sun-Long Luo Guang-Can Guo Qin Wang 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 University of Posts and Telecommunications Ministry of Education Nanjing 210003 China Academy of Mathematics and Systems Science Chinese Academy of Sciences 100190 Beijing China Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China

We present a scheme for the practical decoy-state quantum key distribution with heralded single-photon source. In this scheme, only two-intensity decoy states are employed. However, its performance can approach the asymptotic case of using infinite decoy states. We compare it with the standard three-intensity decoy-state method, and through numerical simulations, we demonstrate its significant improvement over the three-intensity method in both the final key rate and the secure transmission distance. Furthermore, when taking statistical fluctuations into account, a very high key generation rate can still be obtained even at a long transmission distance.

关键词： QUANTUM mechanics PHOTON number COMPUTER simulation DISTRIBUTION (Probability theory) PARAMETER estimation

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Packet sending algorithm based on bundle protocol in DTN networks

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Jilin Daxue Xuebao (Gongxueban)/Journal of Jilin University (Engineering and technology Edition) 2012年第SUPPL. 1期42卷 285-289页

作者： Wang, Kun Yu, Yue Zhang, Yu-Hua Guo, Huang Wang, Lin-Lin Key Lab. of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

Bundle and block were introduced into DTN transmission protocol, which shred data into bits to deal with frequent interruption in DTN network. Bundle and LTP protocol in DTN transmission layer were put forward, and the impact of block size on transmission efficiency was investigated when network environment probably vary dramatically in a short time. Finally we put forward a Bundle sending algorithm that dynamically changes its strategy in DTN network to achieve the best transmission efficiency and system performance. Simulation results show that selecting proper size of data block can increase the transmission effectiveness.

关键词： Efficiency

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