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arXiv 2017年

作者： Wu, Xiaohuan Zhu, Wei-Ping Yan, Jun Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 China Department of Electrical and Computer Engineering Concordia University Montreal Canada School of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing China

The low-rank matrix reconstruction (LRMR) approach is widely used in direction-of-arrival (DOA) estimation. As the rank norm penalty in an LRMR is NP-hard to compute, the nuclear norm (or the trace norm for a positive semidefinite (PSD) matrix) has been often employed as a convex relaxation of the rank norm. However, solving a nuclear norm convex problem may lead to a suboptimal solution of the original rank norm problem. In this paper, we propose to apply a family of nonconvex penalties on the singular values of the covariance matrix as the sparsity metrics to approximate the rank norm. In particular, we formulate a nonconvex minimization problem and solve it by using a locally convergent iterative reweighted strategy in order to enhance the sparsity and resolution. The problem in each iteration is convex and hence can be solved by using the optimization toolbox. Convergence analysis shows that the new method is able to obtain a suboptimal solution. The connection between the proposed method and the sparse signal reconstruction (SSR) is explored showing that our method can be regarded as a sparsity-based method with the number of sampling grids approaching infinity. Two feasible implementation algorithms that are based on solving a duality problem and deducing a closed-form solution of the simplified problem are also provided for the convex problem at each iteration to expedite the convergence. Extensive simulation studies are conducted to show the superiority of the proposed methods. Copyright © 2017, The Authors. All rights reserved.

关键词： Covariance matrix

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CPC: A novel content popularity compensation algorithm for intelligent wireless router in user centric network

CPC: A novel content popularity compensation algorithm for i...

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International Conference on Intelligent System and Knowledge Engineering, ISKE

作者： Xiaoyong Lin Jie Ma Zeqiu Zhang Chao Chen Yun Xia Yang Yu Tingting Qiu Xiaoming Wang College of Tongda Nanjing University of Posts and Telecommunications Yangzhou China College of Communication & Information Engineering Nanjing University of Posts and Telecommunications Nanjing China Ministry of Education Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Nanjing China

User centric network (UCN) brought a new concept of all routers to be intelligent and definable, intelligent wireless terminals implement more video online service than general webpage exploring service, in the time of content is the king, how to provide a best user experience for the video content user under intelligent wireless routers(IWR) is a key focus in the current research of user centric network. This paper proposed a scheme of intelligent pipe between Policy server and IWR, and designed a novel content popularity compensation (CPC) algorithm in user centric network framework, the IWR obtained the user attributes and video content popularity, used the parameter of content popularity compensation index (CPI) to integrate the classified user weight (CUW) and content popularity level (CPL), the modified satisfaction degree (MSD) was designed to replace of the general index of user satisfaction degree, such as linear satisfaction degree (LSD) and simple logarithmic satisfaction (SLS). The scheduling rule was to get a maximized system MSD, and the measurement of user average satisfaction (UAS) was the evaluation standard of CPC. The simulations results showed that the CPC got the better performance than that of routine algorithms, such as max-min fairness (MMF) and Utility function (ULF), the CPC algorithm could push on the intelligent wireless router in smart home and bring a novel video content quality of experience (QoE) of future wireless video online users.

关键词： Bandwidth wireless communication Resource management Servers wireless sensor networks Telecommunications

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Measurement-Device-Independent Quantum Secure Direct communication

arXiv

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arXiv 2018年

作者： Zhou, Zeng-Rong Sheng, Yu-Bo Niu, Peng-Hao Yin, Liu-Guo Long, Gui-Lu State Key Laboratory of Low-dimensional Quantum Physics Beijing100084 China Department of Physics Tsinghua University Beijing100084 China Beijing National Research Center for Information Science and Technology Beijing100084 China School of Information and Technology Tsinghua University Beijing100084 China Collaborative Innovation Center of Quantum Matter Beijing100084 China Beijing Academy of Quantum Information Beijing100084 China Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing210003 China College of Telecommunications & Information Engineering Nanjing University of Posts and Telecommunications Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing210003 China

Quantum secure direct communication (QSDC) is the technology to transmit secret information directly through a quantum channel without neither key nor ciphertext. It provides us with a secure communication structure that is fundamentally different from the one that we use today. In this Letter, we report the first measurement-device-independent(MDI) QSDC protocol with sequences of entangled photon pairs and single photons. It eliminates security loopholes associated with the measurement device. In addition, the MDI technique doubles the communication distance compared to those without using the technique. We also give a protocol with linear optical Bell-basis measurement, where only two of the four Bell-basis states could be measured. When the number of qubit in a sequence reduces to 1, the MDI-QSDC protocol reduces to a deterministic MDI quantum key distribution protocol, which is also presented in the Letter. Copyright © 2018, The Authors. All rights reserved.

关键词： Quantum communication

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Biased decoy-state reference-frame-independent quantum key distribution

arXiv

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arXiv 2017年

作者： Zhu, Jian-Rong Zhang, Chun-Mei Guo, Guang-Can Wang, Qin Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing210003 China Key Laboratory of Quantum Information CAS University of Science and Technology of China Hefei230026 China

Without actively aligning the reference frames, the reference-frame-independent quantum key distribution (RFI-QKD) can generate secure keys even when the reference frames drift slowly. Here, we propose a new scheme on the decoy-state RFI-QKD, where the basis assignments of two legitimate parties are biased, reducing the fraction of mismatched-basis data. When accounting for statistical fluctuations under different misalignments of reference frames, we investigate the performance of biased decoy-state RFI-QKD with full parameter optimization. We also make a clear comparison between the new scheme with other practical schemes, e.g., unbiased decoy-state RFI-QKD and biased decoy-state BB84-QKD. Simulation results demonstrate that the new proposed biased decoy-state RFI-QKD can significantly improve the performance (secret key rate and secure transmission distance) of practical QKD systems. Copyright © 2017, The Authors. All rights reserved.

关键词： Quantum cryptography

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An Expressive, Lightweight and Secure Construction of key Policy Attribute-Based Cloud Data Sharing Access Control

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Journal of Physics: Conference Series 2017年第1期910卷

作者： Guofen Lin Hanshu Hong Yunhao Xia Zhixin Sun The Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing China

Attribute-based encryption (ABE) is an interesting cryptographic technique for flexible cloud data sharing access control. However, some open challenges hinder its practical application. In previous schemes, all attributes are considered as in the same status while they are not in most of practical scenarios. Meanwhile, the size of access policy increases dramatically with the raise of its expressiveness complexity. In addition, current research hardly notices that mobile front-end devices, such as smartphones, are poor in computational performance while too much bilinear pairing computation is needed for ABE. In this paper, we propose a key-policy weighted attribute-based encryption without bilinear pairing computation (KP-WABE-WB) for secure cloud data sharing access control. A simple weighted mechanism is presented to describe different importance of each attribute. We introduce a novel construction of ABE without executing any bilinear pairing computation. Compared to previous schemes, our scheme has a better performance in expressiveness of access policy and computational efficiency.

关键词：

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PRIVACY-PRESERVING K-NN COMPUTATION OVER ENCRYPTED CLOUD DATA WITHOUT key SHARING

PRIVACY-PRESERVING K-NN COMPUTATION OVER ENCRYPTED CLOUD DAT...

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2016 4th IEEE International Conference on Cloud Computing and Intelligence Systems（IEEE CCIS2016）

作者： ShaoHui Wang Tian Liu Fu Xiao Ruchuan Wang College of Computer Nanjing University of Posts and Telecommunications Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Key Lab of Broadband Wireless Communication and Sensor Network Technology

ISBN: (纸本)9781509012572

As a frequently used query operation for online applications,secure k-nearest neighbors(k-NN)computation on encrypted cloud data has received much *** this paper,we focus on the problem of supporting efficient k-NN computation over encrypted cloud data while data owner cannot share his secret keys with query *** give a security analysis of the scheme proposed by Zhu et al.[16],and the analysis shows the scheme cannot provide query privacy at *** we design a new efficient construction to support efficient k-NN computation over encrypted cloud data without key ***,security analysis is presented to demonstrate the new scheme can provide data privacy and query privacy in the Known Ciphertext Model.

关键词： cloud computing k-nearest neighbors computation privacy Known Ciphertext Model

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Effective Prediction Mode Decision Scheme Concerning Scene Switch

Effective Prediction Mode Decision Scheme Concerning Scene S...

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International Conference on wireless communications and Signal Processing

作者： Wei Pu Dong Hu Education Ministry's Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications

ISBN: (纸本)9781509028610

In HEVC, prediction mode decision is essential for efficient coding in applications. While many fast algorithms have been designed to reduce the candidate modes, the features of scene switch frames have seldom been considered. These frames usually have no relationship with the previous frames. Thus, intra modes should be used. In this paper, we propose a simple and efficient Hash-based algorithm. It evaluates the motion intensity of videos and can detect the occurrence of scene switch efficiently. Then chooses the best prediction modes among intra ones directly for CUs in these frames. Experimental results show that it achieves 42% to 53% time saving of the switch frame prediction. Meanwhile, as the prediction time of a switch frame is about 5 to 13 times over that of a normal continuous frame, the algorithm can achieve an outstanding improvement in the prediction of the whole video, especially when dealing with multi-scene videos.

关键词： Mode decision Intra mode Motion intensity Scene switch

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A Normalization Model for Analyzing Multi-Tier Millimeter Wave Cellular networks

arXiv

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arXiv 2017年

作者： Xiong, Siqing Wang, Lijun Kwak, Kyung Sup Bai, Zhiquan Wang, Jiang Li, Qiang Han, Tao School of Electronic Information and Communications Huazhong University of Science and Technology Wuhan China School of Electronic Information Wuhan University Wuhan China Faculty of information science and technology Wenhua College Wuhan China Department of Information and Communication Inha university Incheon Korea Republic of School of Information Science and Engineering Shandong University Jinan China Shanghai Research Center for Wireless Communications Shanghai China Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China Key lab of wireless sensor network and communication Chinese Academy of Sciences Shanghai China

—Based on the distinguishing features of multi-tier millimeter wave (mmWave) networks such as different transmit powers, different directivity gains from directional beamforming alignment and path loss laws for line-of-sight (LOS) and non-line-of-sight (NLOS) links, we introduce a normalization model to simplify the analysis of multi-tier mmWave cellular networks. The highlight of the model is that we convert a multi-tier mmWave cellular network into a single-tier mmWave network, where all the base stations (BSs) have the same normalized transmit power 1 and the densities of BSs scaled by LOS or NLOS scaling factors respectively follow piecewise constant function which has multiple demarcation points. On this basis, expressions for computing the coverage probability are obtained in general case with beamforming alignment errors and the special case with perfect beamforming alignment in the communication. According to corresponding numerical exploration, we conclude that the normalization model for multi-tier mmWave cellular networks fully meets requirements of network performance analysis, and it is simpler and clearer than the untransformed model. Besides, an unexpected but sensible finding is that there is an optimal beam width that maximizes coverage probability in the case with beamforming alignment errors. Copyright © 2017, The Authors. All rights reserved.

关键词： wireless networks

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Load Balanced Coding Aware Multipath Routing for wireless Mesh networks

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Chinese Journal of Electronics 2015年第1期24卷 8-12页

作者： SHAO Xing WANG Ruchuan HUANG Haiping SUN Lijuan College of Computer Nanjing University of Posts and Telecommunications College of Information Engneering Yancheng Institutue of Technology Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Key Lab of Broadband Wireless Communication and Sensor Network Technology

The growth of network coding opportunities is considered the unique optimization goal by most current network coding based routing algorithms for wireless mesh networks. This usually results in flows aggregation problem in areas with coding opportunities, and degrades the network performance. This paper proposes a Load balanced coding aware multipath routing(LCMR)for wireless mesh networks. To facilitate the evaluation of discovered multiple paths and the tradeoffs between coding opportunity and load balancing, a novel routing metric, Load balanced coding aware routing metric(LCRM) is presented, which considers the load degree of nodes when detects coding opportunities. LCMR could spread traffic over multipath to further balance load. Simulation results demonstrate that LCMR could evenly spread the traffic over the network with increasing network throughput in a heavy load at the expense of some coding opportunities.

关键词： Load balanced Coding aware Multipath Routing wireless mesh networks.

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T-QoS-aware based parallel ant colony algorithm for services composition

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Journal of Systems Engineering and Electronics 2015年第5期26卷 1100-1106页

作者： Lin Zhang Kaili Rao Ruchuan Wang College of Computer Nanjing University of Posts and Telecommunications Institute of Computer Technology Nanjing University of Posts and Telecommunications Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Key Lab of Broadband Wireless Communication and Sensor Network Technology Nangjing University of Posts and Telecommunications

In order to make cloud users get credible, high-quality composition of services, the trust quality of service aware(TQoS-aware) based parallel ant colony algorithm is proposed. Our approach takes the service credibility as the weight of the quality of service, then calculates the trust service quality T-QoS for each service, making the service composition situated in a credible environment. Through the establishment on a per-service T-QoS initialization pheromone matrix, we can reduce the colony’s initial search time. By modifying the pheromone updating rules and introducing two ant colonies to search from different angles in parallel,we can avoid falling into the local optimal solution, and quickly find the optimal combination of global solutions. Experiments show that our approach can combine high-quality services and the improvement of the operational success rate. Also, the convergence rate and the accuracy of optimal combination are improved.

关键词： services composition trust service quality ant colony algorithm parallel

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