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arXiv 2018年

作者： Feng, Youhong Yan, Shihao Yang, Zhen Yang, Nan Yuan, Jinhong Key Lab. of Ministry of Education in Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 College of Physics and Electronic Information Engineering Anhui Normal University Wuhu241000 China Research School of Engineering Australian National University CanberraACT Australia School of Engineering Macquarie University NSW2109 Australia Research School of Engineering Australian National University CanberraACT2600 Australia School of Electrical Engineering and Telecommunications University of New South Wales SydneyNSW2052 Australia

In this work, we propose a novel beamforming design to enhance physical layer security of a non-orthogonal multiple access (NOMA) system with the aid of artificial noise (AN). The proposed design uses two scalars to balance the useful signal strength and interference at the strong and weak users, which is a generalized version of the existing beamforming designs in the context of physical layer security for NOMA. We determine the optimal power allocation among useful signals and AN together with the two optimal beamforming scalars in order to maximize the secrecy sum rate (SSR). Our asymptotic analysis in the high signal-to-noise ratio regime provides an efficient and near-optimal solution to optimizing the beamforming scalars and power allocation coefficients. Our analysis indicates that it is not optimal to form a beam towards either the strong user or the weak user in NOMA systems for security enhancement. In addition, the asymptotically optimal power allocation informs that, as the transmit power increases, more power should be allocated to the weak user or AN signals, while the power allocated to the strong user keeps constant. Our examination shows that the proposed novel beamforming design can significantly outperform two benchmark schemes. Copyright © 2018, The Authors. All rights reserved.

关键词： Beamforming

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A high-resolution DOA estimation method with a family of nonconvex penalties

arXiv

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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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TA3C: Teaching-Oriented Adaptive Wi-Fi Authorized Access Control Based on CSI 12

TA3C: Teaching-Oriented Adaptive Wi-Fi Authorized Access Con...

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12th International Conference on Mobile Ad-Hoc and sensor networks, MSN 2016

作者： Xiao, Fu Chen, Jing Xie, Xiaohui Sun, Lijuan Wang, Ruchuan College of Computer Nanjing University of Posts and Telecommunications Jiangsu China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Jiangsu China Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Jiangsu China

ISBN: (纸本)9781509056965

Wi-Fi has been widely deployed with the rapid development of wireless communication technique. Wi-Fi hotspots are popular in campus, making convenient wireless network access possible. However, during class teaching, in order to avoid students browsing the web based on Wi-Fi hotspots and distracting, we hope Wi-Fi hotspots adaptively shield network access to students in the classroom, while grant access to users outside the classroom. In this work, we prototype TA3C system, a teaching-oriented adaptive Wi-Fi authorized access control scheme, using Channel State Information (CSI) to locate instead of coarse-grained and temporally unstable Received Signal Strength Indication (RSSI). CSI can distinguish multipath signals, stay stable in the same propagation environment, and show different characteristics in different propagation environments, based on which, we can distinguish outdoor and indoor environments, and identify user's location to decide whether to offer him wireless network access or not. Experiment results show that TA3C effectively achieve adaptive Wi-Fi authorized access control, which provides a guarantee for the quality of class teaching. Compared to traditional indoor localization techniques, TA3C does not need accurate location information but simply recognizes user's location indoors or outdoors, which means it does not need dedicated hardware, realizing the low-cost indoor localization technique. © 2016 IEEE.

关键词： Access control

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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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Quantum Secure Direct communication with Quantum Memory

引用

Physical Review Letters 2017年第22期118卷 220501-220501页

作者： Wei Zhang Dong-Sheng Ding Yu-Bo Sheng Lan Zhou Bao-Sen Shi Guang-Can Guo Key Laboratory of Quantum Information Chinese Academy of Sciences University of Science and Technology of China Hefei Anhui 230026 China Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei Anhui 230026 China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

Quantum communication provides an absolute security advantage, and it has been widely developed over the past 30 years. As an important branch of quantum communication, quantum secure direct communication (QSDC) promotes high security and instantaneousness in communication through directly transmitting messages over a quantum channel. The full implementation of a quantum protocol always requires the ability to control the transfer of a message effectively in the time domain; thus, it is essential to combine QSDC with quantum memory to accomplish the communication task. In this Letter, we report the experimental demonstration of QSDC with state-of-the-art atomic quantum memory for the first time in principle. We use the polarization degrees of freedom of photons as the information carrier, and the fidelity of entanglement decoding is verified as approximately 90%. Our work completes a fundamental step toward practical QSDC and demonstrates a potential application for long-distance quantum communication in a quantum network.

关键词： Quantum communication Quantum entanglement Quantum information with atoms & light Quantum memories Atomic ensemble

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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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An anonymous ONS resolving model with trust mechanism

Boletin Tecnico/Technical Bulletin

引用

Boletin Tecnico/Technical Bulletin 2017年第3期55卷 111-118页

作者： Wang, Huqing Sun, Zhixin College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing210016 China College of Communication and Information Engineering Nanjing University of Posts and Telecommunications Nanjing210003 China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing Nanjing210003 China

Security of the Object Naming Service (ONS) resolving model is discussed in this paper and an anonymous ONS resolving model with trust mechanism is presented. This model has the following characteristics: firstly, the zero knowledge proof protocol based on elliptic curve is applied;secondly, only certifier and verifier are involved during certification, which can get rid of the bondage of trusted third-party platform;and thirdly, in order to improve efficiency, the concept of trust value is introduced. Once certified, many times of resolving services can be provided. The number of resolving service is determined by trust value. Through theoretical analysis and experimental simulation, the model has the advantages of creativity, anonymity, feasibility, and resistance against replay attack.

关键词： Internet of things

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Turbulence mitigation scheme based on multiple-user detection in an orbital-angular-momentum multiplexed system

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Chinese Physics B 2016年第11期25卷 316-323页

作者：邹丽王乐赵生妹陈汉武 Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications School of Electronics and Information Nantong University Key Laboratory of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications School of Computer Science and Engineering College of Software Engineering Southeast University

Atmospheric turbulence（AT） induced crosstalk can significantly impair the performance of a free-space optical（FSO）communication link using orbital angular momentum（OAM） *** this paper,we propose a multiple-user detection（MUD） turbulence mitigation scheme in an OAM-multiplexed FSO communication ***,we present a MUD equivalent communication model for an OAM-multiplexed FSO communication link under *** the equivalent model,each input bit stream represents one user＇s *** deformed OAM spatial modes caused by AT,instead of the pure OAM spatial modes,are used as information carriers,and the overlapping between the deformed OAM spatial modes are computed as the correlation coefficients between the ***,we present a turbulence mitigation scheme based on MUD idea to enhance AT tolerance of the OAM-multiplexed FSO communication *** the proposed scheme,the crosstalk caused by AT is used as a useful component to deduce users＇ *** numerical results show that the performance of the OAM-multiplexed communication link has greatly improved by the proposed *** the turbulence strength C_n^2 is 1 × 10^（-15） m^（-2/3）,the transmission distance is 1000 m and the channel signal-to-noise ratio（SNR）is 26 dB,the bit-error-rate（BER） performance of four spatial multiplexed OAM modes l_m = ＋ 1,＋2,＋3,＋4 are all close to 10-5,and there is a 2-3 fold increase in the BER performance in comparison with those results without the proposed *** addition,the proposed scheme is more effective for an OAM-multiplexed FSO communication link with a larger OAM mode topological charge *** proposed scheme is a promising direction for compensating the interference caused by AT in the OAM-multiplexed FSO communication link.

关键词： turbulence mitigation momentum angular deformed crosstalk topological multiplexing orbital turbulent

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Online energy management for a sustainable smart home with an HVAC load and random occupancy

arXiv

引用

arXiv 2017年

作者： Yu, Liang Jiang, Tao Zou, Yulong Key Laboratory of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing210003 China Wuhan National Laboratory for Optoelectronics School of Electronics Information and Communications Huazhong University of Science and Technology Wuhan430074

—In this paper, we investigate the problem of minimizing the sum of energy cost and thermal discomfort cost in a long-term time horizon for a sustainable smart home with a Heating, Ventilation, and Air Conditioning (HVAC) load. Specifically, we first formulate a stochastic program to minimize the time average expected total cost with the consideration of uncertainties in electricity price, outdoor temperature, renewable generation output, electrical demand, the most comfortable temperature level, and home occupancy state. Then, we propose an online energy management algorithm based on the framework of Lyapunov optimization techniques without the need to predict any system parameters. The key idea of the proposed algorithm is to construct and stabilize four queues associated with indoor temperature, electric vehicle charging, and energy storage. Moreover, we theoretically analyze the feasibility and performance guarantee of the proposed algorithm. Extensive simulations based on real-world traces show the effectiveness of the proposed algorithm. Copyright © 2017, The Authors. All rights reserved.

关键词： Stochastic systems

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Fog-assisted operational cost reduction for cloud data centers

arXiv

引用

arXiv 2017年

作者： Yu, Liang Jiang, Tao Zou, Yulong Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing210003 China Wuhan National Laboratory for Optoelectronics School of Electronics Information and Communications Huazhong University of Science and Technology Wuhan430074 China

In this paper, we intend to reduce the operational cost of cloud data centers with the help of fog devices, which can avoid the revenue loss due to wide-area network propagation delay and save network bandwidth cost by serving nearby cloud users. Since fog devices may not be owned by a cloud service provider, they should be compensated for serving the requests of cloud users. When taking economical compensation into consideration, the optimal number of requests processed locally by each fog device should be decided. As a result, existing load balancing schemes developed for cloud data centers can not be applied directly and it is very necessary to redesign a cost-ware load balancing algorithm for the fog-cloud system. To achieve the above aim, we first formulate a fog-assisted operational cost minimization problem for the cloud service provider. Then, we design a parallel and distributed load balancing algorithm with low computational complexity based on Proximal Jacobian Alternating Direction Method of Multipliers (PJ-ADMM). Finally, extensive simulation results show the effectiveness of the proposed algorithm. Copyright © 2017, The Authors. All rights reserved.

关键词： Fog

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