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International Conference on Transparent optical networks

作者： Xuelin Yang Xiaonan Hu Zanwei Shen Hao He Weisheng Hu Chenglin Bai State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai P.R. China Shandong Key Laboratory of Optical Communication Science and Technology Liao Cheng University Liaocheng P.R. China

ISBN: (纸本)9781467378819

We propose and demonstrate physical layer security schemes via implementation of chaotic signal scrambling such as partial transmit sequence (PTS) and selected mapping (SLM) techniques in orthogonal frequency-division multiplexing passive optical network (OFDM-PON). The digital chaotic sequences are employed in PTS/SLM schemes to encrypt the OFDM data, which provides a huge key space to enhance the physical layer confidentiality. Transmission of 8.9Gb/s 16QAM encrypted OFDM signals is demonstrated over 20km standard single-mode fiber, which shows the security enhancement against malicious eavesdropping or exhaustive attacks. Moreover, the proposed secure schemes improve the OFDM transmission performance since the peak-to-average power ratio (PAPR) of the OFDM signals is significantly reduced by the signal scrambling.

关键词： Chaos Peak to average power ratio Encryption optical network units

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Three-Color Two-Photon Three-Axis Digital Scanned Light-Sheet Microscopy (3c2p3a-DSLM)

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Microscopy and Microanalysis 2015年第S3期21卷 719-720页

作者： Weijian Zong Zuosheng Liu Fuzeng Niu Shaowa Li Jia Zhao Aimin Wang Liangyi Chen The State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Molecular Medicine Peking University Beijing 100871 China Department of Cognitive Sciences Institute of Basic Medical Sciences Beijing 100850 State Key Laboratory of Advanced Optical Communication System and Networks School of Electronics Engineering and Computer Science Peking University Beijing 100871 China

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In vivo visualization of pancreatic X-cell function in zebrafish using dual-color two-photon three-axis digital scanned light-sheet microscopy

In vivo visualization of pancreatic X-cell function in zebra...

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第九届亚洲生物物理大会

作者： Jia Zhao Weijian Zong Fuzheng Niu Xuan Zheng Aiming Wang Yanmei Liu Liangyi Chen The State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Molecular Medicine Peking University China Department of Cognitive Sciences Institute of Basic Medical Sciences State Key Laboratory of Advanced Optical Communication System and Networks School of Electronics Engineering and Computer Science Peking University

Pancreatic beta-cell plays a central role in the body blood homeostasis by systematically activating glucose uptake after food intake. Diabetes arises when beta-cells are unable to meet insulin demand in the body, either due to a decrease in beta-cell mass or deterioration of beta-cell function [1]. A potential strategy is to generate massive functional beta-cells in vitro from stem cells before transplantation into patients to correct the glucose intolerance. Despite recent progresses, generation of fully functional pancreatic beta-cells in vitro is still not accomplished, which is due to the little understanding of functional maturation of pancreatic beta-cells during development in vivo. To address this question, we aim to study the functional maturation of islet beta-cells of transgenic zebrafish at different development stages in vivo. To achieve this goal, we have updated our previous two-photon three-axis digital scanned light-sheet microscopy(2P3A-DSLM)[3] in the following aspects: 1) two individual high-power femtosecond lasers with two fast Pockels cells for intensity modulation to compensate for the inhomogeneous excitation along the tunable acoustic grin(TAG) scanning range, 2) a system to scan the lightsheet in three dimensions 3) a three-axis movable sample stage coupled with a fast piezo-Z on the emission objective to collect three dimensional fluorescence signals rapidly. 4) an EMCCD cameras and a channel-split device to enable simultaneous dual-color detection of weak fluorescence *** further generated a ins:Rcamp1.07 transgenic zebrafish line, which could be used to monitor glucose-evoked Ca2+ oscillation in pancreatic beta-cells in vivo. Using this fish line, we show an important role of blood circulation per se in promoting insulin-positive cells into glucose responding, insulin-secreting matured beta-cells in vivo.

关键词： In vivo visualization of pancreatic X-cell function in zebrafish using dual-color two-photon three-axis digital scanned light-sheet microscopy

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Non-blocking 2×2 switching unit based on nested silicon microring resonators with high extinction ratios and low crosstalks

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Chinese Science Bulletin 2014年第22期59卷 2702-2708页

作者： Jiayang Wu Xinhong Jiang Ting Pan Pan Cao Liang Zhang Xiaofeng Hu Yikai Su State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong University

In this paper,we propose and demonstrate a2 9 2 optical Benes switching unit based on two nested silicon microring resonators(MRRs)monolithically integrated on a silicon-on-insulator(SOI)*** extinction ratios(ERs)of about 44.7/38.0 dB and low crosstalk values of about-37.5/-45.2 dB at cross/bar states are obtained with the fabricated *** operation principle is theoretically studied and the switching function is verified by system demonstration experiments with 10 and12.5 Gb/s non-return-to-zero(NRZ)*** switching speed on the order of gigahertz based on free carrier effect in silicon is also experimentally demonstrated.

关键词：切换功能消光比谐振器微环嵌套非阻塞串音器具

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Analyzing and Modeling Spatio-Temporal Dependence of Cellular Traffic at City Scale

Analyzing and Modeling Spatio-Temporal Dependence of Cellula...

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IEEE International Conference on communications

作者： Xiaming Chen Yaohui Jin Siwei Qiang Weisheng Hu Kaida Jiang State Key Lab of Advanced Optical Communication System and Network Shanghai Jiao Tong University Network and Information Center Shanghai Jiao Tong University

ISBN: (纸本)9781467364300

Traffic characteristics over space and time constitute an important aspect of cellular networks in consideration of resource provision, traffic engineering and system optimization. Despite recent progress in revealing temporal dynamics and spatial inhomogeneity of cellular traffic, limited knowledge about traffic dependence is gained. One of challenges comes from the absence of sustained observations at a network-wide scale. In this paper, we make an analysis on the week-long traffic generated by a large population of users in a city of China, and model traffic dependence along both space and time dimensions. The evaluation results suggest connections between spatio-temporal dependence of cellular traffic and the organization of human lives. Region differences are observed to impact traffic dependence to a great extent. Additionally, interactive knowledge between space and time enhances traffic prediction with a decrease in root-mean-square error of 2.8%～25.2%. We believe that these achievements will benefit multiple research and development areas such as network deploying and simulation researches.

关键词： Spatio-temporal dependence Traffic modeling Mobile measurement Correlation analysis Tide effects

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Five-partite entanglement generation in a high-Q microresonator

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Physical Review A 2015年第4期91卷 042311-042311页

作者： Yutian Wen Xufei Wu Rongyu Li Qiang Lin Guangqiang He State Key Lab of Advanced Optical Communication Systems and Networks Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China Department of Electrical and Computer Engineering University of Rochester New York 14627 USA

We propose to produce five-partite entanglement via cascaded four-wave mixing in a high-Q microresonator that may become a key to future one-way quantum computation on chip. A theoretical model is presented for the underlying continuous-variable entanglement among the generated comb modes that is expansible to more complicated scenarios. We analyze the entanglement condition when the van Loock and Furusawa criteria are violated and discuss the device parameters for potential experimental realization that may be utilized to build an integrated compact five-partite entanglement generator. The proposed approach exhibits great potential for future large-scale integrated full optical quantum computation on chip.

关键词： MICRORESONATORS (Optoelectronics) COMB filters QUANTUM computing QUANTUM systems QUANTUM states

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Simultaneous microwave frequency transfer and time synchronization based mode-locked pulse train over 120 km fiber

Simultaneous microwave frequency transfer and time synchroni...

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Pacific Rim Conference on Lasers and Electro-Optics (CLEO/Pacific Rim)

作者： Xing Chen Jinlong Lu Jian Zhang Yifan Cui Xing Lu Xusheng Tian Cheng Ci Bo Liu Hong Wu Tingsong Tang Kebin Shi Zhigang Zhang State Key Laboratory of Advanced Optical Communication System and Networks Peking University Beijing P. R. China State Key Laboratory for Mesosconic Physics Peking University Beijing China School of Electronic Information and Optical Engineering Nankai University Tianjin China Beijing Satellite Navigation Center Beijing China

We demonstrate feed-forward digital compensation technique applied in both precise frequency transfer and time synchronization. The fractional frequency instability was 6.18×10 -20 at 2000 s and RMS variation of... 详细信息

ISBN: (纸本)9781467371100

关键词： Synchronization Time-frequency analysis Frequency synchronization optical fiber networks optical fiber amplifiers

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Decentralized Dynamic Spectrum Access in Full-Duplex Cognitive Radio networks

Decentralized Dynamic Spectrum Access in Full-Duplex Cogniti...

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IEEE International Conference on communications

作者： Yun Liao Tianyu Wang Kaigui Bian Lingyang Song Zhu Han State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Beijingh China Electrical and Computer Engineering Department University of Houston Houston TX USA

In the dynamic spectrum access (DSA) paradigm for cognitive radio networks (CRNs), one of the commonly used Medium Access Control (MAC) schemes is designed on basis of the popular carrier sensing multiple access with collision avoidance. However, this proposal suffers from two major problems that may significantly decrease the system performance: (1) collision among the secondary users (SUs) can hardly be detected, thus leading to the secondary transmission failures, and (2) SUs cannot abort transmission when collision occurs, making the long collision duration possible. In this paper, we propose a new cognitive MAC protocol for efficient DSA based on full-duplex CRNs (FD-CRNs), where SUs are able to perform simultaneous spectrum sensing and data transmission owing to full-duplex techniques. Specifically, SUs can detect the collision during transmission, so as to reduce the collision time and improve secondary network performance. Analytical results include the derivations of key design parameters such as the collision ratio with the PU, spectrum usage ratio, optimal contention window size, and the performance comparisons with the conventional DSA in half-duplex CRNs (HD-CRNs), which are further confirmed by simulation results.

关键词： Sensors Cognitive radio Media Access Protocol Simulation Dynamic spectrum access High definition video

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Simultaneously mitigating self-heating induced distortion and chirp effect of DML in TWDM-PON system using nonlinear modulation curve of EAM

Simultaneously mitigating self-heating induced distortion an...

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International Conference on Transparent optical networks

作者： Hanlin Feng Shilin Xiao Mable P. Fok The State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai China College of Engineering The University of Georgia Athens Georgia USA

ISBN: (纸本)9781467378819

In this paper, we propose an upstream receiver for time and wavelength division multiplexed passive optical network (TWDM-PON) system to simultaneously mitigate self-heating induced distortion and chirp effect of directly modulated laser (DML). Using the nonlinear modulation curve of electro-absorption modulator (EAM), signal distortion is easily suppressed after aligning to the zero-slope region of nonlinear modulation curve. Thus, the dilemma between chirp management filtering and large wavelength shift generated by self-heating effect can be solved. We experimentally validate signal distortion compensation of 1 μs burst length with 10 Gb/s data rate and chirp management performance of 25 km, 45 km and 65 km single mode fiber (SMF) is also analysed.

关键词： Chirp Modulation Nonlinear distortion optical distortion Passive optical networks Receivers

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optical single-sideband WDM nyquist 32-QAM SC-FDE transmission system with direct detection

Optical single-sideband WDM nyquist 32-QAM SC-FDE transmissi...

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Asia communications and Photonics Conference, ACPC 2014

作者： Wang, Rongshan Zou, Kaiheng Wang, Dan Zhang, Fan Chen, Zhangyuan State Key Laboratory of Advanced Optical Communication System and Networks Peking University Beijing100871 China

125 Gbit/s optical single side band (OSSB) Square-32QAM wavelength-divisionmultiplexed direct detection over 75.1km SSMF transmission has been successfully demonstrated with a subcarrier frequency band of 2.9 GHz and ... 详细信息

ISBN: (纸本)9781557528520

关键词： Photonics

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