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arXiv 2019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 National Laboratory of Solid State Microstructures Nanjing University Nanjing210093 China

The simplest single-photon entanglement is the entanglement of the vacuum state and the single-photon state between two path modes. The verification of the existence of single-photon entanglement has attracted extensive research interests. Here, based on the construction of Bell’s inequality in wave space, we propose a new method to verify single photon entanglement. Meanwhile, we define the wave state in two-dimensional space relative to the photon number state, and propose a method to measure it. Strong violation of Bell inequality based on joint measurement of wave states indicates the existence of single photon entanglement with certainty. Wave state entanglement obtained from Fourier transform of single photon entanglement and the corresponding measurement protocols will provide us with more information-carrying schemes in the field of quantum information. The difference in the representation in photon-number space and wave space implies the wave-particle duality of single photon entanglement. Copyright © 2019, The Authors. All rights reserved.

关键词： Particle beams

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Phase matching quantum key distribution based on single-photon entanglement

arXiv

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arXiv 2019年

作者： Li, Wei Wang, Le 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 National Laboratory of Solid State Microstructures Nanjing University Nanjing210093 China

Two time-reversal quantum key distribution (QKD) schemes are the quantum entanglement based device-independent (DI)-QKD and measurement-device-independent (MDI)-QKD. The recently proposed twin field (TF)-QKD, also known as phase-matching (PM)-QKD, has improved the key rate bound from O(η) to O(√η) with η the channel transmittance. In fact, TF-QKD is a kind of MDIQKD but based on single-photon detection. In this paper, we propose a different PM-QKD based on single-photon entanglement, referred to as SEPM-QKD, which can be viewed as a time-reversed version of the TF-QKD. Detection loopholes of the standard Bell test, which often occur in DI-QKD over long communication distances, are not present in this protocol because the measurement settings and key information are the same quantity which is encoded in the local weak coherent state. We give a security proof of SEPM-QKD and demonstrate in theory that it is secure against all collective attacks and beam-splitting attacks. The simulation results show that the key rate enjoys a bound of O (√η) with respect to the transmittance. SEPM-QKD not only helps us understand TF-QKD more deeply, but also hints at a feasible approach to eliminate detection loopholes in DI-QKD for long-distance communications. Copyright © 2019, The Authors. All rights reserved.

关键词： Quantum cryptography

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Dynamic Range Impact on 3D MIMO Channel Characteristics in Rural-Macro Scenario at 3.5 GHz

Dynamic Range Impact on 3D MIMO Channel Characteristics in R...

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European Conference on Antennas and Propagation

作者： Weite Zhang Lei Tian Zhongyuan Wu Jianhua Zhang Yi Zheng Jingmin Cao Key Lab of Universal Wireless Communications Ministry of Education State Key Lab of Networking and Switching Technology Beijing University of Posts and Telecommunications Mailbox NO.92 100876 Beijing China China Mobile Research Institude Beijing China National Key Laboratory of Science and Technology on Blind Signal Processing Chengdu Sichuan China

ISBN: (纸本)9781785618154;9781785618161

Rural-macro (RMa) is an important scenario for fifth generation (5G) deployment, and there is a strong diffraction in RMa making it difficult to distinguish between line-of-sight (LoS) and non-line-of-sight (NLoS) case. Since the environmental condition is closely related to the dynamic range of channel impulse response (CIR), this paper studies the dynamic range impact on characteristics of three dimensional (3D) multiple-input multiple-output (MIMO) channels based on 3.5 GHz measurement campaign in RMa. The space-alternating generalized expectation-maximization (SAGE) algorithm is employed to estimate multipath component parameters. The channel statistical characteristics, channel capacity and eigenvalues of CIR matrix are calculated for different CIR dynamic ranges. The results show that the delay spread, the angle spread, the channel capacity and the sub-channel correlation are linearly related to the dynamic range of CIR. Thus, the results give a new perspective to study channel characteristics based on CIR dynamic range in RMa scenario.

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Comparative Channel Study of Ray Tracing and Measurement for an Indoor Scenario at 28 GHz

Comparative Channel Study of Ray Tracing and Measurement for...

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European Conference on Antennas and Propagation

作者： Jinnan Zhan Jianhua Zhang Lei Tian Xinzhuang Zhang Pan Tang Jianwu Dou Hewen Wei Key Lab of Universal Wireless Communications Ministry of Education State Key Lab of Networking and Switching Technology Beijing University of Posts and Telecommunications Mailbox NO.92 100876 Beijing China Wireless Algorithm Department Product R&D system ZTE Corp. Ltd. 201210 Shanghai China National Key Laboratory of Science and Technology on Blind Signal Processing 610041 Chengdu Sichuan China

The millimeter wave communication is important for future wireless systems. In this paper, the channel characteristics at 28 GHz in an indoor scenario are researched based on ray tracing (RT) simulation and measurement. In the RT simulation, various configurations, such as different number of reflections, diffractions and penetrations are used. As for the measurement, two setups are implemented in order to analyze more parameters. Setup one is that biconical antennas are used at both the transmitter (TX) and receiver (RX). The other setup is that horn antenna at RX is rotated 360° in azimuth with a step of 5° when an omni-directional antenna located at TX. Meanwhile, antenna is rotated one circle with an elevation angle of 10°, 0° and -10°, respectively. Path loss and K-factor are analyzed firstly, and analysis results indicate the RT result with 1 or 2 reflections, 1 diffractions and 5 penetrations in this conference room is closest to the measurement result and channel models in 3GPP TR 38.901. Then, the root mean square (RMS) delay spread and RMS angular spread are investigated, which shows the value of measurement is a bit larger than RT because of the limitation of azimuth and elevation step. According to all the results, 1-2 reflections, 1 diffraction and 5 penetrations can be used in RT for future analysis of indoor scenario at 28 GHz.

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A Novel Clustering Method Based on Density Peaks and Its Validation by Channel Measurement

A Novel Clustering Method Based on Density Peaks and Its Val...

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European Conference on Antennas and Propagation

作者： Hanqing Xue Lei Tian Yuxiang Zhang Chao Wang Jianhua Zhang Wei Li Hewen Wei Key Lab of Universal Wireless Communications Ministry of Education State Key Lab of Networking and Switching Technology Beijing University of Posts and Telecommunications P. O. Box 92 Beijing 100876 China Department of Electrical Engineering Northern Illinois University DeKalb IL 60115 National key laboratory of science and technology on blind signal processing Chengdu Sichuan 610041 China

ISBN: (纸本)9781785618154;9781785618161

In this paper, cluster centers are defined as local maxima in the density which is called density peaks. We use an algorithm based on density peaks to cluster multipath components (MPCs) whose parameters are estimated by the space-alternating generalized expectation-maximization (SAGE) algorithm. To validate its performance, we apply it to the data from a channel measurement in an indoor scenario at 28 GHz and compare it to the widely used KPowerMeans algorithm with the same distance metric of multiple component distance (MCD). Through the results, we find it can cluster MPCs more accurately validated by Calinski-Harabasz (CH) and Davies-Bouldin (DB) indices. More importantly, it overcomes the shortcoming of setting the number of clusters manually because we can determine the cluster centers automatically. Besides, the efficiency of DP clustering is far superior to KPowerMeans because what it needs is only a distance matrix and we only need to compute it once. At the end, statistical analysis of clusters are presented to provide insights in channel modeling of millimeter wave.

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An Enhanced LMMSE Channel Estimation under High Speed Railway Scenarios

An Enhanced LMMSE Channel Estimation under High Speed Railwa...

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IEEE International Conference on communications Workshops

作者： Qing Tang Hang Long Haojun Yang Yuli Li Wireless Signal Processing and Network (WSPN) Lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications (BUPT) 100876 China

ISBN: (纸本)9781509015269

With the rapid deployment of the high speed railway (HSR), the wireless communication in HSR has been one of the indispensable scenarios in the fifth generation (5G) communications. In order to improve the performance of the orthogonal frequency division multiplexing (OFDM) system in the HSR scenarios, we propose an enhanced linear minimum mean square error channel estimation scheme based on multi-path Doppler frequency offset (DFO) estimation in this paper. The proposed scheme can estimate DFO of each path, and generate the frequency and time channel correlation more accurately, which can improve the accuracy of channel estimation in the HSR scenarios. Simulation results show that the proposed scheme can reduce the channel estimation error and achieve attractive gain in the HSR scenarios.

关键词： Channel estimation OFDM Estimation Correlation 5G mobile communication Frequency-domain analysis wireless communication

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Realization of remote sensing image segmentation based on K-means clustering

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IOP Conference Series: Materials Science and Engineering 2019年第7期490卷

作者： Yanhong Wang Denghui Li Yuying Wang Guangxi Key Lab of Wireless Wideband Communication & Signal Processing Guilin China Institute Of Information Technology of Guilin University of Electronic Technology Key Laboratory of Cognitive Radio and Information Processing Ministry of Education (Guilin University of Electronic Technology) GUET Guilin China School of Computer Science and Information Security of GUET

Segmentation of remote sensing image is the key technology of positioning system. Firstly, we transform the remote sensing image from RGB pace to lab space. Then, three centres are iterated by using K- means algorithm. Finally, in order to eliminate the influence, the closed operation of mathematical morphology is used to correct the segmented image. The results show that it can segment the road from the remote sensing image in lab mode, by using K-means clustering algorithm. Moreover, lab mode is more suitable for k-mean than other modes.

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A Two-Stage Allocation Scheme for Delay-Sensitive Services in Dense Vehicular Networks

A Two-Stage Allocation Scheme for Delay-Sensitive Services i...

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IEEE International Conference on communications Workshops

作者： Haojun Yang Long Zhao Lei Lei Kan Zheng Wireless Signal Processing and Network (WSPN) Lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications (BUPT) State Key Lab of Rail Traffic Control and Safety Beijing Jiaotong University

ISBN: (纸本)9781509015269

Driven by the rapid development of wireless communication system, more and more vehicular services can be efficiently supported via vehicle-to-everything (V2X) communications. In order to allocate radio resource with the reasonable implementation complexity in dense urban intersection, a two-stage allocation algorithm is proposed in this paper, whose main objective is to minimize delay and ensure reliability. In particular, as for the first stage, the allocation policy is based on traffic density information (TDI), which is different from utilizing channel state information (CSI) and queue state information (QSI) in the second stage. Moreover, in order to reflect the influence of TDI on delay, a macroscopic vehicular mobility model is employed in this paper. Simulation results show that the proposed algorithm can acquire an asymptotically optimal performance with the acceptable complexity.

关键词： Low latency and high reliability Radio resource allocation Dense urban intersection Macroscopic mobility model Resource utilization TLX1NB gene Tolylene Diisocyanate wireless communication systems Legal Services Dense Allocation Algorithm order Traffic density

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USER INTEREST BASED DISTRIBUTED COOPERATIVE CACHING AND SHARING IN wireless NETWORKS 5

USER INTEREST BASED DISTRIBUTED COOPERATIVE CACHING AND SHAR...

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2016 5th IEEE International Conference on Network Infrastructure and Digital Content(IC-NIDC 2016)

作者： Zheng Guo Hao Jin Chenglin Zhao Dong Liang Wireless Signal Processing and Network Lab Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

ISBN: (纸本)9781509012473

Distributed cache is considered to be one of the key solutions to meet the explosively increasing demand for mobile data *** plenty of related research is burgeoning,most of them mainly focus on caching at routing nodes or base stations,leaving the potential caching ability of the users’ smart devices *** paper proposes a cooperative caching and sharing scheme of users’ smart devices,where the smart devices would prefer to cache contents the user is interested in and share their cached contents through D2 D *** provide both the analytical and simulation results to show our scheme’s efficiency.

关键词： User cooperation Caching and sharing D2D

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Traffic scenario recognition and analysis for wireless cellular system: From social network perspective

Traffic scenario recognition and analysis for wireless cellu...

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2016 IEEE Canadian Conference on Electrical and Computer Engineering, CCECE 2016

作者： Yi, Zhenglei Peng, Yiran Wang, Tong Zhang, Xing Wang, Wenbo Key Laboratory of Universal Wireless Communication Ministry of Education Wireless Signal Processing and Network Lab Beijing University of Posts and Telecommunications Beijing100876 China

ISBN: (纸本)9781467387217

In wireless cellular system, due to the convergence of user behavior, there usually exists some typical scenarios which exhibit different traffic patterns, e.g. stadium, campus and central business district (CBD). Accurate traffic scenario recognition and analysis will lead to more efficient resource management and better QoS (quality-of-service) provision. In this paper, with the idea of social network analysis, a base station social network (BSSN) based method is proposed to recognize and analyze the typical traffic scenarios in wireless cellular system. Firstly, we construct a BSSN to visualize the hidden relationship between base stations (BSs) by using previously measured spatial-temporal wireless traffic data. Then, a modularity optimization based method is used to discover community structure in BSSN. Analytical results show that each community in BSSN corresponds to a typical wireless scenario with a unique traffic pattern in cellular system. Experimental results illustrate that our proposed BSSN based method is general enough and achieves satisfactory performance in traffic scenario recognition and analysis. © 2016 IEEE.

关键词： Base stations

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