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第十八届全国量子光学学术会议

作者：刘晨曦 Tong-Jun Liu Si Wang Xiao-Run Wang Jian Li Qin Wang 南京邮电大学 Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and TelecommunicationsMinistry of Education

Quantum random numbers are a fundamental resource to security and cryptography. Based on the intrinsically random processes, quantum random number generators（QRNGs） provides an opportunity to certify genuine random numbers. All implementations of QRNGs that invoke device-independent（DI）, the violation of Bell inequality are necessary to guarantee that the outcomes of the measurements cannot be determined in advance. For the single Clauser-Horne-Shimony-Holt（CHSH） inequality, it is not optimal with respect to randomness certification. Since local projective measurement are performed, one random bit can be certified from the maximally entangled two-qubit states. Recently, Andersson et al. [Phys. Rev. A 97, 012314（2018）] had proven that the device-independent certification can obtain two random bits through the maximum quantum violation of Gisin’s elegant Bell inequality. Here, we report a proof-of-principle realization of optimal randomness certification with practical photonic apparatus. In our experiment, we implement two kinds of qubit measurement, mutually unbiased bases（MUBs） and symmetric informationally complete positive operator-valued measures（SIC-POVM） of four-outcomes, respectively. Through randomness extractor, including Toeplitz-hashing extractor and an improved linear feedback shift register（LFSR）, we finally extracted random bit string which have good uniformity and pass all randomness tests of the NIST.

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Improving Q-factor of electromagnetically induced transparency based on mirrored metasurface

Improving Q-factor of electromagnetically induced transparen...

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IEEE Information technology and Mechatronics Engineering Conference (ITOEC)

作者： Haiming Li Youyun Xu College of Telecommunications & Information Engineering Nanjing University of Posts and Telecommunications Nanjing China Broadband Wireless Communication and Sensor Network Technology Key Lab of Ministry of Education Nanjing University of Posts and Telecommunications Jiangsu China

ISBN: (纸本)9781538653746

Improving Q-factor of analogy of electromagnetically induced transparency (EIT-like) based on the symmetric and asymmetric quasi-dark mode has been numerically demonstrated. The Q-factor of EIT-like based on the symmetric quasi-dark mode (mirrored metasurface) is an order of magnitude larger than the Q-factor of EIT-like based on the asymmetric quasi-dark mode. The low radiative loss of the symmetric quasi-dark mode causes the improved Q-factor. Furthermore, the proposed way of improving the Q-factor has important application in microwave, terahertz and optical metasurface.

关键词： Q-factor Metamaterials Couplings Wires Tomography Current distribution Telecommunications

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Adaptive spatial modulation for visible light communications with an arbitrary number of transmitters

arXiv

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arXiv 2018年

作者： Wang, Jin-Yuan Ge, Hong Zhu, Jian-Xia Wang, Jun-Bo Dai, Jianxin Lin, Min Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 China National Mobile Communications Research Laboratory Southeast University Nanjing210096 China School of Science Nanjing University of Posts and Telecommunications Nanjing210003 China

As a power and bandwidth efficient modulation scheme, the optical spatial modulation (SM) technique has recently drawn increased attention in the field of visible light communications (VLC). To guarantee the number of bits mapped by the transmitter's index at each timeslot is an integer, the number of transmitters (i.e., light-emitting diodes) in the SM based VLC system is often set be a power of two. To break the limitation on the required number of transmitters and provide more design flexibility, this paper investigates the SM based VLC with an arbitrary number of transmitters. Initially, a channel adaptive bit mapping (CABM) scheme is proposed, which includes three steps: Bit mapping in space domain, bit mapping in signal domain, and the channel adaptive mapping. The proposed CABM scheme allows operation with an arbitrary number of transmitters, and is verified to be an efficient scheme through numerical results. Based on the CABM scheme, the information-theoretical aspects of the SM based VLC are analyzed. The theoretical expression of the mutual information is first analyzed. However, it is very hard to evaluate system performance. To obtain more insights, a lower bound of the mutual information is derived, which is in closedform. Both theoretical analysis and numerical results show that the gap between the mutual information and its lower bound is small. Finally, to further improve the system performance, the precoding scheme is proposed for the SM based VLC. Numerical results show that the system performance improves dramatically when using the proposed precoding scheme. Copyright © 2018, The Authors. All rights reserved.

关键词： Visible light communication

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Simplification of I-Vector Extraction for Speaker Identification

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Chinese Journal of Electronics 2016年第6期25卷 1121-1126页

作者： XU Longting YANG Zhen SUN Linhui Broadband Wireless Communication and Sensor Network Technology Key Lab Nanjing University of Posts and Telecommunications

The identity vector(i-vector) approach has been the state-of-the-art for text-independent speaker recognition, both identification and verification in recent years. An i-vector is a low-dimensional vector in the socalled total variability space represented with a thin and tall rectangular matrix. This paper introduces a novel algorithm to improve the computational and memory requirements for the application. In our method, the series of symmetric matrices can be represented by diagonal expression,sharing the same dictionary, which to some extent is analogous to eigen decomposition, and we name this algorithm Eigen decomposition like factorization(EDLF). Similar algorithms are listed for comparison, in the same condition,our method shows no disadvantages in identification accuracy.

关键词： Speaker identification Closed-set I-vector Symmetric matrix factorization

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Cross-layer resource allocation based on equivalent bandwidth in OFDMA systems

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Journal of Systems Engineering and Electronics 2016年第4期27卷 754-762页

作者： Su Pan Cheng Li Sheng Zhang Danwei Chen Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts & Telecommunications

A quality of service（QoS） guaranteed cross-layer resource allocation algorithm with physical layer, medium access control（MAC） layer and call admission control（CAC） considered simultaneously is proposed for the full IP orthogonal frequency division multiple access（OFDMA） communication system, which can ensure the quality of multimedia services in full IP *** algorithm converts the physical layer resources such as subcarriers, transmission power, and the QoS metrics into equivalent bandwidth which can be distributed by the base station in all three layers. By this means, the QoS requirements in terms of bit error rate（BER）, transmission delay and dropping probability can be guaranteed by the cross-layer optimal equivalent bandwidth allocation. The numerical results show that the proposed algorithm has higher spectrum efficiency compared to the existing systems.

关键词： resource allocation equivalent bandwidth crosslayer optimization orthogonal frequency division multiple access（OFDMA）

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network Selection Algorithm Based on Group Decision Making for Heterogeneous wireless networks 9

Network Selection Algorithm Based on Group Decision Making f...

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2017 9th IEEE International Conference on Communication Software and networks (ICCSN 2017)

作者： Ran Luo Su Zhao Qi Zhu College of Telecommunications & Information Engineering Nanjing University of Posts and Telecommunications National Mobile Communications Research Laboratory Southeast University Jiangsu Key Lab of Wireless Communications Nanjing University of Posts and Telecommunications Key Lab on Wideband Wireless Communications and Sensor network Technology of Ministry of Education Nanjing University of Posts and Telecommunications

ISBN: (纸本)9781509038237;9781509038220

Multimode terminals running multiple services at the same time are increasingly common, in response to this phenomenon, a network selection algorithm based on group decision making for heterogeneous wireless networks is presented in this paper. The algorithm considers each service from the terminal as a decision-maker, and obtains the weight vector of all network attributes for each service by the analytic hierarchy process, then uses the group decision making to synthesize these weight vectors. At the same time, the utility function is used to normalize the network attributes. At last, the network selection is made according to the synthesized weight vector and attribute utility. The simulation results show that the proposed algorithm is far superior to the TOPSIS in satisfying the Qo S requirements of different class of services, and can solve the problem of network selection for a group of services from a multi-service terminal.

关键词： network selection multi-service terminal group decision making Qo S requirement

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High-dimensional measurement-device-independent quantum key distribution based on spatial basis

arXiv

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arXiv 2018年

作者： Li, Wei Zhao, Shengmei Nanjing University of Posts and Telecommunications Institute of Signal Processing and Transmission Nanjing210003 China Nanjing University of Posts and Telecommunications Key Lab Broadband Wireless Communication and Sensor Network Ministy of Education Nanjing210003 China Sunwave Communications Hangzhou310053

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Multichannel analysis for uplink heterogeneous cellular networks with flexible cell association 7

Multichannel analysis for uplink heterogeneous cellular netw...

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7th IET International Conference on wireless, Mobile and Multimedia networks, ICWMMN 2017

作者： Hu, Han Wang, Hong Yang, Jie Pan, Ziyu Jiangsu Key Lab of Wireless Communications Key Lab on Wideband Wireless Communications and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Jiangsu Nanjing210003 China Communication Engineering Department Nanjing Institute of Technology Jiangsu Nanjing211167 China

ISBN: (纸本)9781785615153

In this paper, an analytical framework is developed to evaluate the uplink outage and spatial blocking performance in a multichannel heterogeneous cellular network. A weighted uplink cell association criterion and random channel reuse scheme are integrated in the considered model. The spatial locations of base stations (BSs) per tier as well as the users (UEs) are modelled as independent Poisson point processes. Because of the maximum transmit power constraint, a UE is allowed to communicate with its serving BS only when it has sufficient transmit power to support full channel inversion. With the aid of stochastic geometry, uplink spatial blocking and outage probability are respectively derived, which are validated to be quite close to the true distributions by extensive simulations. Thus, the theoretical analysis developed in this paper is valid. Then, the effect of network parameters, such as weighted factor, power cut-off threshold, and channel reuse factor, can be evaluated by quickly closed-form expressions rather than error-prone system-level simulations. © Institution of Engineering and technology. All rights reserved.

关键词： Outages

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Voiceprint recognition based on BP Neural network and CNN

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Journal of Physics: Conference Series 2019年第3期1237卷

作者： Dong Zhipeng Wei Jingcheng Xu Yumin Meng Qingmin Wang Xiaoming Key Laboratory of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education College of Telecommunications & Information Engineering Nanjing 210003 China National Mobile Communications Research Lab Southeast University Nanjing 210096 China

At present, speech recognition has become a key technology of human-computer interaction, which can be used in semantic recognition and speaker identification and other related applications. This paper focuses on a speaker identification scene and the technical design. Because artificial neural network has the ability to distinguish complex classification boundaries, plenty of work on speech recognition had studied multi-layer perceptual networks to improve the accuracy of classification where back propagation method (BP algorithm) has been used. In the studied scheme, when the test objects (speakers) speak the same isolated word, the identification system can judge who the speaker is by identifying the voice voiceprint of different people. Our design not only considers the recognition based on BP as well as its variant, but also explores the voiceprint recognition based on convolution neural network (CNN). Secondly, the network structure and performance are also compared in detail.

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A fast covariance matrix reconstruction method for two-dimensional direction-of-arrival estimation

A fast covariance matrix reconstruction method for two-dimen...

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2017 IEEE International Conference on Acoustics, Speech, and Signal Processing, ICASSP 2017

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 Nanjing China Department of Electrical and Computer Engineering Concordia University Montreal Canada

ISBN: (纸本)9781509041176

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. © 2017 IEEE.

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

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