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Enhanced solutions for resource conflict in GMPLS controlled optical network

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 123-127页

作者： HUANG Zhi-tong HUA Yi-qiang LU Yue-ming JI Yue-feng, xu da-xiong Key Laboratory of Optical Communications and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 China

This article discusses the issue of resource conflict in the generalized multi-protocol label switching （GMPLS） controlled optical network. Based on the analysis of the current random rebuilding mechanism and its drawbacks, this article presents two enhanced solutions for improvement, namely, the priority-based resource allocation mechanism and the network management system （NMS） based sequential resource allocation mechanism. Experimental results show that the presented mechanisms perform better than the original random rebuilding solution in terms of the connection setup/recovery time and successful rate.

关键词： GMPLS automatically switched optical network (ASON) resource reservation protocol (RSVP) control plane resource conflict

Performance analysis of broadband satellite communication system based on OFDM/TDM

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 37-42,77页

作者： TIAN Qing-hua ZHANG Qi TAO Ying LIU Nai-jin XIN Xiang-jun ZHANG Li-jia xu da-xiong Institute of Optical Communication and Optoelectronics Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications Institute of Telecommunication Satellite China Academy of Space Technology

Orthogonal frequency division multiplexing （OFDM） is attracting more attention for its capability of high speed transmission. However, the OFDM possesses an obvious shortage in its high ratio of the peak power to the average power （PAPR）, which has become the main issue holding it back to be applied to the broadband satellite communication system. OFDM combined with time division multiplexing （TDM）, dividing the subcarriers of OFDM into some blocks in time tune, can decrease the high PAPR of OFDM. Meanwhile, the advantages of OFDM can be preserved. In this paper, OFDM/TDM is applied to the broadband satellite communication system. This paper theoretically analyses OFDM/TDM system model as well as its restraining effect on PAPR, and proposes frequency domain multiplexing-pilot （FDM-Pilot） channel estimation algorithm. Simulation results show OFDM/TDM in broadband satellite communication system has approving performance and decreased the PAPR.

关键词： OFDM/TDM broadband satellite communication system PAPR channel estimation

Impact of polarization mode dispersion and nonlinear effect on 40 Gbit/s dense wavelength division multiplexing system

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Frontiers of Electrical and Electronic Engineering in China 2006年第3期1卷 361-366页

作者： SUN xue-ming ZHANG Hui-jian ZUO Meng GU Wan-yi xu da-xiong Optical Communications Center Beijing University of Posts and TelecommunicationsBeijing 100876China Department of Basic Courses Beijing Electronic and Science Technology InstituteBeijing 100070China Beijing Electronic and Science Technology Institute Beijing 100070China

Dense wavelength division multiplexing(DWDM)system is the ultimate selection as an optical communica-tion system because of its high speeds and ***,the fiber nonlinear effects and polarization mode dispersion severely limit the performance of the system when signal propagates at 40 Gbit/s in a single *** coupled nonlinear Schrödinger equations of a single channel in DWDM,which are all considered factors of group veloc-ity dispersion(GVD),self phase modulation(SPM),cross phase modulation(XPM),four wave mixing(FWM)and polarization mode dispersion(PMD),are derived,while their number results are obtained with extended split-step Fourier ***,to analyze the impacts of the fiber nonlinear effects and PMD on the optical communication system,the simulated results of an 8×40 Gbit/s DWDM system are discussed under different conditions respec-tively.

关键词： optical communication system DWDM nonlin-ear effect PMD

Impact of Reflection Induced Noise on AM-VSB CATV Lightwave Systems

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The Journal of China Universities of Posts and Telecommunications 2000年第Z1期 7-12页

作者： HAN Yu-guo , GU Wan-yi , xu da-xiong (Beijing University of Posts and Telecommunications, Beijing 100876, P. R. China)

The effect of reflection on the performance of AM-VSB CATV lightwave systems is analyzed. Usually, there are three kinds of reflection existing in the AM-VSB CATV lightwave systems: multipath interference (MPI), double Rayleigh backscattering (DRB) and external optical feedback. The MPI and external optical feedback can be neglected owing to using the FC/APC connectors and isolated DFB lasers in the system link. It is shown theoretically and experimentally that the DRB is the limitation of the noise induced by reflection.

关键词： CATV lightwave systems double Rayleigh backscattering AM-VSB

Optimization of Key Parameters in 622-Mb/s Amplitude Shift Keying Labeled 40-Gb/s Return to Zero Differential Phase Shift Keying Optical Switching Network

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Semiconductor Photonics and Technology 2008年第1期14卷 17-21页

作者： ZHAO Jun-yan XIN Xiang-jun YU Chong-xiu xu da-xiong Key Laboratory of Optical Communication and Lightwave Technologies Beijing University of Posts and Telecommunications Beijing 100876 CHN

Optimized are the label extinction ratio and dispersion compensation of an optical label switching transmission system,which employs 40-Gb/s return to zero differential phase shift keying(RZ-DPSK)payload labeled with 622-Mb/s amplitude shift keying(ASK)control *** our scheme,the receiver sensitivities of payload and label achieves-27.8dBm and-33.5dBm,*** transmitted over 40km,60km and 80km single mode fiber(SMF)(with dispersion compensation)respectively,the payload can be recovered with no power penalty,while the label can be recovered with less than 2dB penalty.

关键词： optical label switching RZ-DPSK/ASK extinction ratio(ER) dispersion compensation orthogonal modulation

A New Anti-Collision Algorithm for Multi-Target Real Time Recognitionin RFID System

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The Journal of China Universities of Posts and Telecommunications 2000年第3期7卷 64-69页

作者： SHEN Yu chao, WANG Hai bo, SHEN Shu qun, xu da xiong (School of Electronic Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,P.R.China) School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

The problem of how to distinguish and recognize more than one target when they are entering the working area of the Radio Frequency Identification( RFID ) system should be considered in design of the system. To avoid signal interference with each other among all targets, an anti collision algorithm as well as the condition of working stability is proposed. The computer simulation shows that the new algorithm will be of advantages in the process of system design.

关键词： radio frequency radio frequency identification antenna anti collision algorithm

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OADM中同频串扰的数值模拟

北京邮电大学学报 2000年第4期23卷 1-5页

作者：程振杰余重秀徐大雄北京邮电大学电子工程学院北京100876

串扰是波分复用光网络中限制光分插复用器容量的一个重要因素 .文中分析了相干和非相干串扰对通过 OADM节点的光信号的影响 ,给出了固定和最佳判决门限两种情况下的光功率恶化 ,并仿真模拟了串扰引入的功率恶化随复用波长数、解复用器... 详细信息

串扰是波分复用光网络中限制光分插复用器容量的一个重要因素 .文中分析了相干和非相干串扰对通过 OADM节点的光信号的影响 ,给出了固定和最佳判决门限两种情况下的光功率恶化 ,并仿真模拟了串扰引入的功率恶化随复用波长数、解复用器隔离度和节点下路波长数的变化情况 ,结果表明相干串扰对系统的影响很大 .与固定判决相比 ,采用最佳判决可以降低串扰影响 .另外采用滤波器也可以抑制串扰 .

关键词：波分复用 OADM 数值模拟同频串扰光纤通信

A Complementary Antenna Array Used inRadio Frequency Identification

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The Journal of China Universities of Posts and Telecommunications 1999年第2期6卷 59-62页

作者： SHEN Yu-chao WANG Hai-bo SHEN Shu-qun xu da-xiong(Department of Electronic Engieering,Beijing University of posts and Telecommunications. Beijing, 100876, P. R. China) Department of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 P. R. China

Antenna array is often used in radio systems to obtain longer recognition distance and more *** forms of antenna array in RFID, with which the radiation Patterns are complemenary, are *** verify the theoretical anal... 详细信息

关键词： radio frequeny antenna radio frequency identthetion

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3相移DFB激光器的数值分析

半导体光电 1999年第5期20卷 337-340页

作者：沈丹勋顾畹仪徐大雄北京邮电大学通信工程学院北京100876

分析了３相移激光器的稳态特性。在分析中，考虑了空间烧孔（ＳＨＢ）及非线性增益等因素。在通用的传输矩阵法（ＴＭＭ）的基础上，通过对ＴＭＭ模型的输入进行向量处理来求解阈值及高于阈值条件下的主模及次模，进而求出单模稳定... 详细信息

分析了３相移激光器的稳态特性。在分析中，考虑了空间烧孔（ＳＨＢ）及非线性增益等因素。在通用的传输矩阵法（ＴＭＭ）的基础上，通过对ＴＭＭ模型的输入进行向量处理来求解阈值及高于阈值条件下的主模及次模，进而求出单模稳定性。这个方法也可用于其他ＤＦＢ

关键词：半导体激光器分布反馈激光器特性分析