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Ad-Hoc and Sensor networks Symposium

作者： Rongqing Zhang Xiang Cheng Liuqing Yang Department of Electrical & Computer Engineering Colorado State University State Key Laboratory of Advanced Optical Communication Systems & Networks School of Electronics Engineering and Computer Science Peking University

ISBN: (纸本)9781479966653

In this paper, we investigate the physical layer security issue in Device-to-Device (D2D) communications underlaying cellular networks. In order to optimize the system secrecy rate of the cellular secure communication, we derive the optimal joint power control solutions of both the cellular communication links and D2D pairs in terms of the secrecy capacity. Furthermore, we propose a secrecy-based joint power and access control (JPAC) scheme with optimum D2D pair selection mechanism that can achieve an improved network secrecy performance with very low computational complexity. Simulation results validate the efficiency of the proposed secrecy-based JPAC scheme.

关键词： Cellular networks Physical layer access control Privacy communication system security communication Research Joints Joints Device-to-device communication System Failure Rate

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SWARM - Strategies for Providing Frequency Containment Reserve Power with a Distributed Battery Storage System

SWARM - Strategies for Providing Frequency Containment Reser...

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IEEE International Energy Conference

作者： David Steber Peter Bazan Reinhard German Computer Science 7 - Chair for Computer Networks and Communication Systems Friedrich-Alexander University Erlangen-Nurnberg

ISBN: (纸本)9781467384643

Virtual power plants can participate in energy markets. This paper presents the modeling approach used in the current research project SWARM for simulating the frequency containment reserve (FCR) power provision with a virtual mass storage. It participates in the German FCR market since July 2015 and is composed of battery energy storage systems (ESSs), which are in fact installed in households with roof-top PV plants and by this means increase the household's internal PV-converted power consumption and offer FCR power at the same time. The paper investigates the effects of more sever restrictions on FCR power provision as have recently been required by the German TSOs. These restrictions translate to relatively small bounds for the state of charge (SOC) of the batteries and have a significant influence on the household's profitability of installing an ESS.

关键词： Central controlled distributed batteries Frequency containment reserve power Internal PV-converted power consumption

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Spontaneous emission rate and optical amplification of Er3+ in double slot waveguide

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science China(Physics,Mechanics & Astronomy) 2015年第12期58卷 166-172页

作者： WANG XingJun JIANG LingJun GUO RuiMin YE Rui ZHOU ZhiPing State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer SciencePeking University Division of Biological Energy and Environmental Measurement National Institute of Metrology

The spontaneous emission(SE) of Er3+ embedded in a double slot dielectric structure was studied by a quantum-electrodynamical formalism. The study shows that the slot width and the position of Er3+ in slot structure have a significant effect on the SE. The double slot waveguides were fabricated by embedding two low-index Er/Yb silicate material layers into high-index silicon. The radiative efficiency of Er3+ in the double slot waveguides is found to be higher than that of the single slot waveguide, which is consistent with the theory simulation. The 0.67 d B signal enhancement at 1.53 ?m in a 4.6-mm-long slot waveguide was observed pumped by 1476 nm laser. These results show the relevance of our model to study the SE processes in multilayer structures and are important for future realization of silicon-compatible active optical devices.

关键词： slot waveguide spontaneous emission rate quantum efficiency

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Energy-Efficient Beamforming for Two-Tier Massive MIMO Downlink

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China communications 2015年第10期12卷 64-75页

作者： XU Guozhen LIU An JIANG Wei XIANG Haige LUO Wu China Mobile Research Institute & The State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Department of Electrical and Computer Engineering Hong Kong University of Science and Technology The State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University

Heterogeneous networks(HetNets)consisting of macro cells with very large antenna arrays and a secondary tier of small cells with a few antennas each can well tackle the contradiction of large coverage of the network and high data rate at the hot ***,it is not permissible to assign orthogonal pilot sequences for all the supported users due to the large ***,we propose a pilot reduction scheme based on the heterogeneous system configurations and the unique topology of this *** reusing of pilot sequences causes the presence of the contaminated channel state information(CSI) and results in receivers' Quality of Service(QoS) *** the contaminated CSI,we provide an energy-efficient beamforming based on minimizing the total power consumption while keeping the QoS constraints satisfied and restricting the QoS outage probability below a given *** applying the approach of Bernstein approximation and semi-definite relaxation,we transform the original intractable chance constrained program to a convex problem *** results show that the average power consumption of the proposed beamforming for our pilot reduction scheme is close to that of the perfect CSI *** our scheme will greatly compress the length of pilot sequence especially for those highly densified network with large number of small cells,it will be crucially helpful to put such two-tier massive multiple-input and multiple-output(MIMO) systems into practice.

关键词： massive MIMO small cell Het-Net energy efficiency

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Hybrid optical pumping of K and Rb atoms in a paraffin coated vapor cell

arXiv

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arXiv 2017年

作者： Li, Wenhao Peng, Xiang Budker, Dmitry Wickenbrock, Arne Pang, Bo Zhang, Rui Guo, Hong State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Center for Quantum Information Technology Peking University Beijing100871 China Helmholtz Institute Mainz Mainz55099 Germany Department of Physics University of California BerkeleyCA94720-7300 United States Nuclear Science Division Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Johannes Gutenberg-University Mainz Mainz55128 Germany College of Science Interdisciplinary Center for Quantum Information National University of Defense Technology Changsha410073 China

Dynamic hybrid optical pumping effects with a radio-frequency-field-driven nonlinear magneto-optical rotation (RF NMOR) scheme are studied in a dual-species paraffin coated vapor cell. By pumping K atoms and probing 87Rb atoms, we achieve an intrinsic magnetic resonance linewidth of 3 Hz and the observed resonance is immune to power broadening and light-shift effects. Such operation scheme shows favorable prospects for atomic magnetometry applications. Copyright © 2017, The Authors. All rights reserved.

关键词： Optical pumping

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Continuous-variable QKD over 50km commercial fiber

arXiv

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arXiv 2017年

作者： Zhang, Yichen Li, Zhengyu Chen, Ziyang Weedbrook, Christian Zhao, Yijia Wang, Xiangyu Huang, Yundi Xu, Chunchao Zhang, Xiaoxiong Wang, Zhenya Li, Mei Zhang, Xueying Zheng, Ziyong Chu, Binjie Gao, Xinyu Meng, Nan Cai, Weiwen Wang, Zheng Wang, Gan Yu, Song Guo, Hong State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Center for Quantum Information Technology Center for Computational Science and Engineering Peking University Beijing100871 China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing100876 China Xanadu 372 Richmond St W TorontoM5V 2L7 Canada China Mobile Group Guangdong Co. Ltd. Guangzhou510623 China Xi’an Uotocom Network Technology Co. Ltd. Xi’an710075 China

The continuous-variable version of quantum key distribution (QKD) offers the advantages (over discrete-variable systems) of higher secret key rates in metropolitan areas, as well as the use of standard telecom components that can operate at room temperature. An important step in the real-world adoption of continuous-variable QKD is the deployment of field tests over commercial fibers. Here we report two different field tests of a continuous-variable QKD system through commercial fiber networks in Xi’an and Guangzhou over distances of 30.02 km (12.48 dB) and 49.85 km (11.62 dB), respectively. We achieve secure key rates two orders-of-magnitude higher than previous field test demonstrations by employing an efficient calibration model with one-time evaluation. This accomplishment is also realized by developing a fully automatic control system which stabilizes system noise, and by applying a rate-adaptive reconciliation method which maintains high reconciliation efficiency with high success probability in fluctuated environments. Our results pave the way to deploy continuous-variable QKD in metropolitan settings. Copyright © 2017, The Authors. All rights reserved.

关键词： Quantum cryptography

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Non-Gaussian postselection and virtual photon subtraction in continuous-variable quantum key distribution

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Physical Review A 2016年第1期93卷 012310-012310页

作者： Zhengyu Li Yichen Zhang Xiangyu Wang Bingjie Xu Xiang Peng Hong Guo State Key Laboratory of Advanced Optical Communication Systems and Networks Center for Computational Science and Engineering and Center for Quantum Information Technology School of Electronics Engineering and Computer Science Peking University Beijing 100871 China Science and Technology on Security Communication Laboratory Institute of Southwestern Communication Chengdu 610041 China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing 100876 China

Photon subtraction can enhance the performance of continuous-variable quantum key distribution (CV QKD). However, the enhancement effect will be reduced by the imperfections of practical devices, especially the limited efficiency of a single-photon detector. In this paper, we propose a non-Gaussian postselection method to emulate the photon substraction used in coherent-state CV QKD protocols. The virtual photon subtraction not only can avoid the complexity and imperfections of a practical photon-subtraction operation, which extends the secure transmission distance as the ideal case does, but also can be adjusted flexibly according to the channel parameters to optimize the performance. Furthermore, our preliminary tests on the information reconciliation suggest that in the low signal-to-noise ratio regime, the performance of reconciliating the postselected non-Gaussian data is better than that of the Gaussian data, which implies the feasibility of implementing this method practically.

关键词： Quantum cryptography

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Towards Dual-functional Radar-communication systems: Optimal Waveform Design

arXiv

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arXiv 2017年

作者： Student, Fan Liu Zhou, Longfei Masouros, Christos Li, Ang Luo, Wu Petropulu, Athina IEEE School of Information and Electronics Beijing Institute of Technology Beijing100081 China Department of Electronic and Electrical Engineering University College London LondonWC1E 7JE United Kingdom State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Beijing100871 China Department of Electronic and Electrical Engineering University College London LondonWC1E 7JE United Kingdom Department of Electrical and Computer Engineering Rutgers State University of New Jersey 94 Brett Road PiscatawayNJ08854 United States

We focus on a dual-functional multi-input-multioutput (MIMO) radar-communication (RadCom) system, where a single transmitter communicates with downlink cellular users and detects radar targets simultaneously. Several design criteria are considered for minimizing the downlink multi-user interference. First, we consider both the omnidirectional and directional beampattern design problems, where the closed-form globally optimal solutions are obtained. Based on these waveforms, we further consider a weighted optimization to enable a flexible trade-off between radar and communications performance and introduce a low-complexity algorithm. The computational costs of the above three designs are shown to be similar to the conventional zero-forcing (ZF) precoding. Moreover, to address the more practical constant modulus waveform design problem, we propose a branch-and-bound algorithm that obtains a globally optimal solution and derive its worst-case complexity as a function of the maximum iteration number. Finally, we assess the effectiveness of the proposed waveform design approaches by numerical results. Copyright © 2017, The Authors. All rights reserved.

关键词： Optimal systems

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Improving the signal-to-noise ratio of ghost imaging with thermal light background by narrow band optical filtering

Improving the signal-to-noise ratio of ghost imaging with th...

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Frontiers in Optics, FiO 2016

作者： Yang, Dongyue Li, Junhui Wu, Guohua Luo, Bin Yin, Longfei Guo, Hong School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing100876 China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Center for Quantum Information Technology Peking University Beijing100871 China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing100876 China

In ghost imaging with narrow-band pseudo-thermal signal embedded in thermal light background, signal-arm narrow band optical filters bring higher value and converging upper limit of the imaging signal-to-noise ratio (... 详细信息

ISBN: (纸本)9781943580194

关键词： Signal to noise ratio

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On-chip light sources for silicon photonics

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Light(science & Applications) 2015年第1期4卷 79-91页

作者： Zhiping Zhou Bing Yin Jurgen Michel State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer SciencePeking UniversityBeijing 100871China Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Serving as the electrical to optical converter,the on-chip silicon light source is an indispensable component of silicon photonic technologies and has long been ***,we briefly review the history and recent progress of a few promising contenders for on-chip light sources in terms of operating wavelength,pump condition,power consumption,and fabrication ***,the performance of each contender is also assessed with respect to thermal stability,which is a crucial parameter to consider in complex optoelectronic integrated circuits(OEICs)and optical ***,III-V-based silicon(Si)lasers formed via bonding techniques demonstrate the best performance and display the best opportunity for commercial usage in the near ***,in the long term,direct hetero-epitaxial growth of III–V materials on Si seems more promising for low-cost,high-yield *** demonstration of high-performance quantum dot(QD)lasers monolithically grown on Si strongly forecasts its feasibility and enormous potential for on-chip *** superior temperature-insensitive characteristics of the QD laser promote this design in large-scale high-density *** Germanium(Ge)-on-Si laser is also competitive for large-scale monolithic integration in the *** with a III-V-based Si laser,the biggest potential advantage of a Ge-on-Si laser lies in its material and processing compatibility with Si ***,the versatility of Ge facilitates photon emission,modulation,and detection simultaneously with a simple process complexity and low cost.

关键词： on-chip light sources optical interconnections optoelectronic integrated circuit silicon photonics

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