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Analysis and prediction of 100 km-scale atmo-spheric duct interference in TD-LTE networks

Journal of communications and Information networks 2017年第1期2卷 66-80页

作者： Ting Zhou Tianyu Sun Honglin Hu Hui Xu Yang Yang Ilkka Harjula Yevgeni Koucheryavy Key Lab of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 201800China School of Information Science and Technology ShanghaiTech UniversityShanghai 201204China Shanghai Research Center for Wireless Communication Shanghai 201204China VTT Technical Research Centre of Finland VTT FI-02044Finland Tampere University of Technology Korkeakoulunkatu 10Tampere FI-33720Finland

Atmospheric ducts are horizontal layers that occur under certain weather conditions in the lower *** signals guided in atmospheric ducts tend to experience less attenuation and spread much farther,i.e,hundreds of *** a large-scale deployed TD-LTE(Time Division Long Term Evolution)network,atmospheric ducts cause faraway downlink wireless signals to propagate beyond the designed protection distance and interfere with local uplink signals,thus resulting in a large outage *** this paper,we analyze the characteristics of ADI atmospheric duct interference(Atmospheric Duct Interference)by the use of real network-side big data from the current operated TD-LTE network owned by China *** analysis results yield the time varying and directional characteristics of *** addition,we proposed an SVM(Support Vector Machine)-classi er based spacial prediction method of ADI by machine learning over combination of real network-side big data and real meteorological ***,an implementation of ADMM(Alternating Direction Methods of Multipliers)framework is proposed to implement a distributed SVM prediction scheme,which reduces data exchange among di erent regions/cities,maintains similar prediction accuracy and is thus of a more practical use to operators.

关键词： TD-LTE interference map atmospheric duct machine learning wireless big data

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On the secrecy performance of Random VLC networks with imperfect CSI and protected zone

arXiv

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arXiv 2019年

作者： Wang, Jin-Yuan Qiu, Yu Lin, Sheng-Hong Wang, Jun-Bo Lin, Min Liu, Cheng 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 Vertical Industry Development Department Baidu China Co. Ltd. Shanghai201210 China

This paper investigates the physical-layer security for a random indoor visible light communication (VLC) network with imperfect channel state information (CSI) and a protected zone. The VLC network consists of three nodes, i.e., a transmitter (Alice), a legitimate receiver (Bob), and an eavesdropper (Eve). Alice is fixed in the center of the ceiling, and the emitted signal at Alice satisfies the non-negativity and the dimmable average optical intensity constraint. Bob and Eve are randomly deployed on the receiver plane. By employing the protected zone and considering the imperfect CSI, the stochastic characteristics of the channel gains for both the main and the eavesdropping channels is first analyzed. After that, the closed-form expressions of the average secrecy capacity and the lower bound of secrecy outage probability are derived, respectively. Finally, Monte-Carlo simulations are provided to verify the accuracy of the derived theoretical expressions. Moreover, the impacts of the nominal optical intensity, the dimming target, the protected zone and the imperfect CSI on secrecy performance are discussed, respectively. Copyright © 2019, The Authors. All rights reserved.

关键词： Visible light communication

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Complete hyperentangled Greenberger-Horne-Zeilinger state analysis for polarization and time-bin hyperentanglement

arXiv

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arXiv 2022年

作者： Zeng, Zhi Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing210003 China School of Physics and Astronomy Shanghai Jiao Tong University Shanghai200240 China

We present an efficient scheme for the complete analysis of hyperentangled Greenberger-Horne-Zeilinger (GHZ) state in polarization and time-bin degrees of freedom with two steps. First, the polarization GHZ state is distinguished completely and nondestructively, resorting to the controlled phase flip (CPF) gate constructed by the cavity-assisted interaction. Subsequently, the time-bin GHZ state is analyzed by using the preserved polarization entanglement. With the help of CPF gate and self-assisted mechanism, our scheme can be directly generalized to the complete Nphoton hyperentangled GHZ state analysis, and it may have potential applications in the hyperentanglement-based quantum communication. © 2022, CC BY.

关键词： Polarization

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An Expanding Ring Prediction and Location Aided AODV Routing Algorithm

An Expanding Ring Prediction and Location Aided AODV Routing...

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International Conference on Information technology, Computer Engineering and Management Sciences (ICM)

作者： Chunling Cheng Jingbo Hao Dengyin Zhang College of Computer Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Jiangsu Province Nanjing University of Posts and Telecommunications Nanjing Jiangsu China Nanjing University of Posts and Telecommunications Nanjing CN

On the battlefield, the cooperative fighting and communication among combat vehicles require higher service level of real-time transmission. Combat vehicles, fast moving and the links, frequent disruption lead to the increase of packet loss rate, packet delay and routing control overhead ratio. This paper proposes an expanding ring prediction and location aided AODV routing algorithm. It improves AODV routing protocol from both routing discovery and maintenance phases. In the routing discovery phase, the algorithm limits the scope of sending RREQ through predicting the topology ring, and during the route maintenance phase, it predicts the motion range of destination node with the information provided by GPS to avoid blindness routing. The simulation results show that the proposed routing algorithm can greatly cut down the overload of combat vehicular network, improve the routing delay and reduce packet loss rate. It can meet the real-time requirements of the service transmission among combat vehicles and also improve the performance of the combat vehicular network.

关键词： Routing Vehicles Delay Prediction algorithms Routing protocols Maintenance engineering Algorithm design and analysis

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Research on the Loading Method of Logistics Vehicle and Cargo Based on IPSO Algorithm

Research on the Loading Method of Logistics Vehicle and Carg...

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第42届中国控制会议

作者： Zewei Zhao Huqing Wang Zhe Sun Lei Xu Guangfu Gong Xiangpeng Xie Zhixin Sun Post Industry Technology Research and Development Center of the State Posts Bureau (Internet of Things Technology) Nanjing University of Posts and Telecommunications Post Big Data Technology and Application Engineering Research Center of Jiangsu Province Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and Telecommunications

Logistics vehicle and cargo matching problem is a typical combination optimization problem,which has important theoretical and application value in the field of logistics *** proved particle swarm optimization(PSO) algorithm is one of the most extensive optimization methods studied in recent years,with excellent global search ability and convergence *** on the IPSO algorithm,this paper proposes an effective IPSO algorithm model for the matching problem of logistics vehicles and goods,and conducts the corresponding comparative *** final experimental results show that the algorithm has good results in practical application and can provide a feasible optimization method for solving the problem of logistics vehicles and goods.

关键词：

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Unmanned Aerial Vehicle Path Planning Based on Improved Intelligent Water Drop Algorithm

Unmanned Aerial Vehicle Path Planning Based on Improved Inte...

引用

International Conference on Instrumentation, Measurement, Computer, communication and Control (IMCCC)

作者： Xixia Sun Su Pan Chao Cai Yanfang Chen Jie Chen Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing China State Key Laboratory for Multispectral Information Processing Technologies School of Automation Huazhong University of Science and Technology Wuhan China Tianjin Zhong Wei Aerospace Data System Technology Co.Ltd Tianjin China

ISBN: (数字)9781538682463

ISBN: (纸本)9781538682470

The unmanned aerial vehicle (UAV) has been a research focus in recent years and the path planner is a key element of the UAV autonomous control module. In this paper, a novel UAV path planning method based on intelligent water drop algorithm is proposed. Firstly, the mathematical model of the UAV path planning problem is presented. Secondly, an improved intelligent water drop algorithm is proposed to solve the UAV path planning model. In the proposed algorithm, a novel path construction mechanism is proposed and an adaptive global soli update mechanism is developed. The proposed algorithm can overcome some shortages of the original ITD algorithm, such as slow search speed, easily falling into local minima, and so on. Experimental results demonstrate that the proposed planner outperforms the original ITD planner in a statistical manner.

关键词： Path planning Heuristic algorithms Optimization Unmanned aerial vehicles Mathematical model Soil Classification algorithms

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Proof-of-Principle Demonstration of Passive Decoy-State Quantum Digital Signatures Over 200 km

引用

Physical Review Applied 2018年第3期10卷 034033-034033页

作者： Chun-Hui Zhang Xing-Yu Zhou Hua-Jian Ding Chun-Mei Zhang Guang-Can Guo Qin Wang Institute of Quantum Information and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Broadband Wireless Communication and Senser Network Technology Key Lab of Ministry of Education NUPT Nanjing 210003 China Telecommunication and Networks National Engineering Research Center NUPT Nanjing 210003 China Key Laboratory of Quantum Information CAS University of Science and Technology of China Hefei Anhui 230026 China

Quantum digital signatures (QDSs) offer the information-theoretic security verified by quantum mechanics to send a message that is robust against forging and repudiation. We report a proof-of-principle demonstration of a passive decoy-state QDS system that can avoid leaking the modulation information of decoy states. To realize this, four local detection events are generated from the idler light of a parametric down-conversion process, and are then used as decoy states to estimate channel parameters more accurately. As a result, we successfully sign a more-than-one-bit message within 7 s at 100 km. Besides, we achieve a transmission distance of 200 km, which represents a further step toward the practical application of QDSs.

关键词： Photon pairs & parametric down-conversion Quantum communication Quantum cryptography

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Practical phase-modulation stabilization in quantum key distribution via machine learning

arXiv

引用

arXiv 2019年

作者： Liu, Jing-Yang Ding, Hua-Jian Zhang, Chun-Mei Xie, Shi-Peng Wang, Qin Institute of quantum information and technology Nanjing University of Posts and Telecommunications Nanjing210003 China Broadband Wireless Communication and Sensor Network TechnologyKey Lab of Ministry of Education Ministry of Education Nanjing210003 China Telecommunication and NetworksNational Engineering Research Center NUPT Nanjing210003 China

In practical implementation of quantum key distributions (QKD), it requires efficient, real-time feedback control to maintain system stability when facing disturbance from either external environment or imperfect internal components. Usually, a"scanning-and-transmitting" program is adopted to compensate physical parameter variations of devices, which can provide accurate compensation but may cost plenty of time in stopping and calibrating processes, resulting in reduced efficiency in key transmission. Here we for the first propose to employ a well known machine learning model, i.e., the Long Short-Term Memory network (LSTM), to predict those physical parameter variations in advance and actively perform real-time control on corresponding QKD devices. Experimentally, we take the phase-coding scheme as an example and run the LSTM model based QKD system for more than 10 days. Experimental results show that we can keep the same level of quantum-bit error rate as the traditional"scanning-and-transmitting" program by employing our new machine learning method, but dramatically reducing the scanning time and resulting in significantly enhanced key transmission efficiency. Furthermore, our present machine learning model should also be applicable to any other QKD systems using any coding scheme or QKD protocols, and thus seems a very promising candidate in large-scale application of quantum communication network in the near future. Copyright © 2019, The Authors. All rights reserved.

关键词： Efficiency

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Manipulating orbital angular momentum entanglement by using the Heisenberg Uncertainty principle

arXiv

引用

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 CO. Hangzhou Zhejiang310053 China

Orbital angular momentum entanglement is one of the most intriguing topics in quantum physics. A broad range of research have been dedicated either to unravel its underlying physics or to expand the entanglement dimensions and degrees. In this paper, we present a theoretical study on the orbital angular momentum entanglement by employing the Heisenberg uncertainty principle to quantum position correlation within the azimuthal region. In this study, we decompose the pump light into a set of pump cone states characterized by their radii. The OAM entanglement can be manipulated by controlling the radius of the pump cone state, the length of the nonlinear crystal and the OAM carried by the pump field,which is followed by a detailed discussion. We expect that our research will bring us a deeper understanding of the OAM entanglement, and will do help to the high-dimensional quantum information tasks based on OAM entanglement. Copyright © 2018, The Authors. All rights reserved.

关键词： Pumps

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Transmit Power Minimization for STAR-RIS Empowered Symbiotic Radio communications

arXiv

引用

arXiv 2023年

作者： Zhou, Chao Lyu, Bin Feng, Youhong Hoang, Dinh Thai The Key Laboratory of Ministry of Education in Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210003 China School of Physics and Electronic Information Anhui Normal University Wuhu241000 China School of Electrical and Data Engineering University of Technology Sydney SydneyNSW2007 Australia

In this paper, we propose a simultaneously transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) empowered transmission scheme for symbiotic radio (SR) systems to make more flexibility for network deployment and enhance system performance. The STAR-RIS is utilized to not only beam the primary signals from the base station (BS) towards multiple primary users on the same side of the STAR-RIS, but also achieve the secondary transmission to the secondary users on another side. We consider both the broadcasting signal model and unicasting signal model at the BS. For each model, we aim for minimizing the transmit power of the BS by designing the active beamforming and simultaneous reflection and transmission coefficients under the practical phase correlation constraint. To address the challenge of solving the formulated problem, we propose a block coordinate descent based algorithm with the semidefinite relaxation, penalty dual decomposition and successive convex approximation methods, which decomposes the original problem into one sub-problem about active beamforming and the other sub-problem about simultaneous reflection and transmission coefficients, and iteratively solve them until the convergence is achieved. Numerical results indicate that the proposed scheme can reduce up to 150.6% transmit power compared to the backscattering device enabled scheme. © 2023, CC BY.

关键词： Iterative methods

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