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IEEE International Conference on Acoustics, Speech and Signal Processing

作者： Xiaohuan Wu Wei-Ping Zhu Jun Yan Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications China

ISBN: (纸本)9781509041183

In this paper, a new method for two-dimensional (2-D) direction-of-arrival (DOA) estimation is proposed. We first reconstruct the covariance matrix of the coarray with block-Toeplitz structure and then retrieve the DOAs. Our method is computationally efficient as supported by the derived closed-form expression for the estimated covariance matrix. Unlike other methods, which require fully loaded arrays, the proposed method can be applied in the case of common rectangular arrays with arbitrary geometries. The estimated azimuth and elevation angles are automatically paired. Moreover, our method is of high estimation accuracy and immune to the angle ambiguity effect. Numerical simulations are carried out to verify the effectiveness of the proposed method.

关键词： 2-D DOA estimation Toeplitz-block-Toeplitz structure generalized rectangular array (GRA)

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QoE-Driven Distributed Media Services in D2D communications Underlaying Cellular networks

QoE-Driven Distributed Media Services in D2D Communications ...

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IEEE International Conference on communications Workshops

作者： Mingkai Chen Lei Wang Jianxin Chen Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education

ISBN: (纸本)9781509015269

Device-to-device (D2D) communication has been widely studied to improve network performance and been considered as a potential technological component for the next generation communication. As Quality of Experience (QoE) is the major determining factor for the media service, we aim at promoting user's QoE Mean of Score (MOS) value for dynamic cellular networks. In this paper, we focus on the problem of heterogeneous media service distribution in D2D communications underlaying cellular networks. Firstly, we propose an innovative distributed media service scheme based on QoE models that jointly solve the massive media content dissemination issue for cellular networks. Moreover, our work maximizes users' QoE satisfaction by jointly considering media-aware, popularity function and priority function. Then, we propose a novel resource allocation algorithm based on the popularity function to optimize the total users' QoE satisfaction and avoid the influence of D2D interference. Numerical simulation results demonstrate the effectiveness of our proposed schemes.

关键词： Cellular networks communication Research Popularity

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Spatial Compression Scheme for Improving the Lifetime of wireless sensor networks

Spatial Compression Scheme for Improving the Lifetime of Wir...

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2017 17th IEEE International Conference on communication technology (ICCT 2017)

作者： Jiasheng Zhou Siguang Chen Yuting Wang Weifeng Lu Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications

How to reduce the number of transmissions or prolong the lifetime of wireless sensor networks（WSNs） has become a research focus. Based on the spatial correlation of sensor readings, in this paper, we propose a spatial compression scheme for improving the lifetime of wireless sensor network to address this issue. This scheme can prolong the lifetime of network significantly by combing LEACH protocol and spatial compression. Meanwhile, the reconstruction precision of original data is high for exploring the spatial correlation of sensor readings fully. Moreover, based on the layered network architecture, the proposed scheme can improve the network loading by selecting the cluster head randomly. Finally, the simulation results confirm that the lifetime of the proposed scheme is longer than other related schemes, and the original data can be reconstructed with high precision.

关键词： wireless sensor networks LEACH protocol compressed sensing spatial compression lifetime

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Thermal effects of the quantum states generated from the isomorphs of PPKTP crystal

arXiv

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arXiv 2018年

作者： Jin, Rui-Bo Chen, Guo-Qun Laudenbach, Fabian Zhao, Shengmei Lu, Pei-Xiang Laboratory of Optical Information Technology Wuhan Institute of Technology Wuhan430205 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Security & Communication Technologies Center for Digital Safety & Security AIT Austrian Institute of Technology GmbH Donau-City-Str. 1 Vienna1220 Austria Quantum Optics Quantum Nanophysics and Quantum Information Faculty of Physics University of Vienna Boltzmanngasse 5 Vienna1090 Austria

We theoretically and numerically investigate the temperature-dependent properties of the biphotons generated from four isomorphs of periodically poled KTiOPO4 (PPKTP): i.e., PPRTP, PPKTA, PPRTA and PPCTA. It is discovered that the first type of group-velocity-matched (GVM) wavelength is decreased by 6.4, 1.2, 8.9, 25.6 and 6.3 nm, while the phase-matched wavelength is decreased by 4.4, -0.4, -1.2, 29.1 and 59.5 nm for PPKTP, PPRTP, PPKTA, PPRTA and PPCTA, respectively, when the temperature is increased from 20 ◦C to 120 ◦C. Although the maximal spectral purity of the heralded single photons is not changed at different temperature, the Hong-Ou-Mandel (HOM) interference shows different patterns due to a shift of the joint spectral amplitude. These thermal effects are very important for precise control of the quantum state for the future applications in quantum information processing, for example, in quantum interference or spectroscopy. Copyright © 2018, The Authors. All rights reserved.

关键词： Quantum optics

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Collusion detector based on G-N algorithm for trust model

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Journal of Systems Engineering and Electronics 2016年第4期27卷 926-935页

作者： Lin Zhang Na Yin Jingwen Liu Ruchuan Wang College of Computer Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nangjing University of Posts and TelecommunicationsNangjing 210003China

In the open network environment, malicious attacks to the trust model have become increasingly serious. Compared with single node attacks, collusion attacks do more harm to the trust model. To solve this problem, a collusion detector based on the GN algorithm for the trust evaluation model is proposed in the open Internet environment. By analyzing the behavioral characteristics of collusion groups, the concept of flatting is defined and the G-N community mining algorithm is used to divide suspicious communities. On this basis, a collusion community detector method is proposed based on the breaking strength of suspicious communities. Simulation results show that the model has high recognition accuracy in identifying collusion nodes, so as to effectively defend against malicious attacks of collusion nodes.

关键词： trust model collusion detector G-N algorithm

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An improved apriori algorithm with prejudging and screening

An improved apriori algorithm with prejudging and screening

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International Conference on Computer, communication and Computational Sciences, ICCCCS 2016

作者： Zhao, Xuejian Li, Dongjun Yuan, Yuan Sun, Zhixin Chen, Yong Key Lab of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China Jiangsu Posts & Telecommunications Planning and Designing Institute Co. LTD Nanjing China Nanjing Longyuan Microelectronic Co. LTD Nanjing China

ISBN: (纸本)9789811037696

Association rule analysis, as one of the significant means of data mining, plays an important role in discovering the implicit knowledge in massive transaction data. Aiming at the inherent defects of the classic Apriori algorithm, this paper proposes IAPS (Improved Apriori with Prejudging and Screening) algorithm. IAPS algorithm adds a prejudging and screening procedure on the basis of the self-join and pruning progress in Apriori algorithm which can reduce and optimize the k-frequent item sets using prior probability. IAPS algorithm simplifies the operation process of mining frequent item sets. Experimental results show that the improved algorithm can effectively reduce the number of scanning databases and reduce the running time of the algorithm. © Springer Nature Singapore Pte Ltd. 2017.

关键词： Association rules

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Users' Media Cloud Assisted D2D communications for Distributed Caching Underlaying Cellular network

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China communications 2016年第8期13卷 13-23页

作者： Mingkai Chen Lei Wang Jianxin Chen Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education The State Key Laboratory of Integrated Services Networks Xidian University

In cellular networks, the proximity devices may share files directly without going through the e NBs, which is called Device-to-Device communications(D2D). It has been considered as a potential technological component for the next generation of communication. In this paper, we investigate a novel framework to distribute video files from some other proximity devices through users' media cloud assisted D2 D communication. The main contributions of this work lie in: 1) Providing an efficient algorithm Media Cloud Cluster Selecting Scheme(MCCSS) to achieve the reasonable cluster; 2) Distributing the optimum updating files to the cluster heads, in order to minimize the expected D2 D communication transmission hop for files; 3) Proposing a minimum the hop method, which can ensure the user obtain required file as soon as possible. Extensive simulation results have demonstrated the efficiency of the proposed scheme.

关键词： device-to-device communication users’ media cloud cache content delivery

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3D shape segmentation via shape fully convolutional networks

arXiv

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arXiv 2017年

作者： Wang, Pengyu Gan, Yuan Shui, Panpan Yu, Fenggen Zhang, Yan Chen, Songle Sun, Zhengxing State Key Lab for Novel Software Technology Nanjing University Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications

We design a novel fully convolutional network architecture for shapes, denoted by Shape Fully Convolutional networks (SFCN). 3D shapes are represented as graph structures in the SFCN architecture, based on novel graph convolution and pooling operations, which are similar to convolution and pooling operations used on images. Meanwhile, to build our SFCN architecture in the original image segmentation fully convolutional network (FCN) architecture, we also design and implement a generating operation with bridging function. This ensures that the convolution and pooling operation we have designed can be successfully applied in the original FCN architecture. In this paper, we also present a new shape segmentation approach based on SFCN. Furthermore, we allow more general and challenging input, such as mixed datasets of different categories of shapes which can prove the ability of our generalisation. In our approach, SFCNs are trained triangles-to-triangles by using three low-level geometric features as input. Finally, the feature voting-based multi-label graph cuts is adopted to optimise the segmentation results obtained by SFCN prediction. The experiment results show that our method can effectively learn and predict mixed shape datasets of either similar or different characteristics, and achieve excellent segmentation results. . Copyright © 2017, The Authors. All rights reserved.

关键词： network architecture

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Channel measurement and modeling for the 15-GHz radio band in an indoor corridor environment

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Journal of communications and Information networks 2017年第2期1卷 102-108页

作者： Hui Xu Wuxiong Zhang Yang Yang Key Lab of Wireless Sensor Network and Communication Chinese Academy of Sciences Shanghai China Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China Shanghai Research Center for Wireless Communications Shanghai China

Traditional mobile communication systems mainly work on the licensed frequency band near or below 3 GHz; however, this band is becoming increasingly crowded. On the other hand, there are abundant unlicensed spectrum resources in higher frequency bands, e.g., 6 GHz, 15 GHz, and 28 GHz, and if those bands are applied, the current spectrum shortage problem could be effectively alleviated. However, the wireless channel characteristics and models are important but still unknown, and thus in this study, extensive measurements and modeling have been conducted to study the characteristics of the high-frequency 15-GHz band. Specifically, a PN(Pseudo Noise) sequence based time-domain measurement system was built and applied to measure the propagation characteristics of the LOS (Line-of-Sight) and NLOS (Non-Line-of-Sight) scenarios in an indoor corridor at 15 GHz. Then, in-depth analysis and modeling on the large-scale characteristics of wireless channels, the relationship between distance and path loss, the path loss exponent, and the shadow fading standard variance are provided. Moreover, the relationship between received power and different elevation angles was studied. In the measurement, two 25-dBi horn antennas with a 10 half-power beam width are used to change elevation angles in the transmitting terminal and azimuth angles in the receiving terminal for all measurement points. The findings and results in this work will serve as a reference and basis for future theoretical studies of the 15-GHz band.

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MPLB: A Load Balance Scheme of Joint Resource Scheduling in Heterogeneous wireless network

MPLB: A Load Balance Scheme of Joint Resource Scheduling in ...

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International Conference on Cyber-Enabled Distributed Computing and Knowledge Discovery, CyberC

作者： Xiaoyong Lin Pengwei Yin Yun Xia Yang Yu Tingting Qiu Xiaoming Wang Lixiang Li Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing China College of Communication & Information Engineering Nanjing University of Posts and Telecommunications Nanjing China

A user terminal with multi-mode wireless interface is always located its position in the covered area of heterogeneous wireless network (HWN), there are too many algorithms about vertical handover (VHO) of multiple attributes decision making (MADM) network selections about HWN. According the analysis of current applications of wireless service, regular service has been classified into four kinds, including voice, video, small data and big data, and the proportions of wireless video and big data service may acquire an unavailable bandwidth for each individual wireless station, which will lead to a heavy load and a lower satisfaction rate. A multiple properties load balance (MPLB) scheme is proposed to solve this joint resource scheduling(JRS) problem properly, MPLB scheme first gave an enhanced architecture including the JSR sub-layer, then model of MPLB is established from the candidate wireless network, five aggregated network performance properties have been defined mathematically, the candidate of best grey relational coefficients (GRC) of grey relational analysis(GRA) algorithm is optimally selected as the final executable scheme, after the description of a general flowchart of MPLB scheme. The simulation results proved the MPLB scheme has a more stable load balance effects than those of VHO, so did most users of MPLB gain higher satisfaction rate, slightly different with the four kinds of service. It can be concluded theoretically that the MPLB scheduling scheme could achieve both the load balance on the service providers side and the increased quality of experience of satisfaction rate on the wireless user side, which would bring out some new thoughts in the future user centric network.

关键词： Distributed computing Knowledge discovery

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