最新刊期
卷 ， 期 6 ， 2014
- 摘要：Ultra-high-speed,ultra-large-capacity and ultra-long-haul（3U）are the forever pursuit of optical communication or even the whole communication industry.As a new mode of communication 3U transmission can greatly promote the next generation of optical internet and broadband mobile communication network development and technological progress,therefore 3U has become the focus of international high-tech intellectual property and competition ground.This paper introduces the scientific problems,key technologies,and important achievements that have been made in 3U transmission.关键词：ultra-high-speed;ultra-large-capacity;ultra-long-haul;optical transmission;high spectral efficiency;optical coding;optical modulation
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发布时间： - 摘要：This paper introduces the principles of unified switching and the key technologies for its implementation,including the cell switching technology and Segmentation And Reassembly（SAR）technology,gives the function block diagrams of the unified switching equipments and describes such issues to be considered in the design as switching efficiency,latency,redundant protection of the switching boards and switching capacity calculation.The results in this paper have been applied to optical transmission equipments with good effects.This technology has obvious technical superiority and it will be one of the key technologies for the next generation telecommunication networks.关键词：unified switching;SAR;service adaptation;multi-service;cell switching
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发布时间： - 摘要：In order to meet the requirements of optical communication systems for high code rate and low bit error rate of errorcorrection codes,we present a novel construction method for QC-LDPC codes on the basis of the nature of the field characteristics of Galois field,which is simple in structure,easy to be encoded and can effectively avoid the girth 4effectively,and use this method to construct an FC-QC-LDPC（3969,3729）code that is suitable for optical communication systems.The simulation results show that when the BER=10-7,the Net Coding Gain（NCG）of the constructed FC-QC-LDPC（3969,3729）code with the code rate of 0.937 is about 0.15 dB higher than that of the QC-LDPC（4288,4020）code,and about 0.35 dB and 2.1dB higher than those of the Linshu-QC-LDPC（3780,3542）code and the classical RS（255,239）code respectively.In addition,its performance is about the same as that of Mackay code but has stronger error-correcting performance.So it is more suitable for high-rate long-haul optical communication systems.关键词：optical communication system;Galois field;QC-LDPC code;NCG
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发布时间： - 摘要：In respect of the security routing in optical networks,this paper proposes a new attack-aware routing algorithm for optical networks based on artificial fish swarm optimization in compliance with the Maximum Light path Attack Radius（MaxLAR）criterion,using the fast search and global optimization ability of the artificial fish swarm algorithm.This algorithm can find out the smallest maximum attack radius in light paths under given conditions,enhance the attack prevention ability of optical networks and minimize the possible damage to light paths caused by the potential physical-layer attacks.Algorithm analysis and Benchmark test function experiments indicate that this algorithm is feasible and has good performance.关键词：optical network;routing;MaxLAR;artificial fish swarm
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发布时间： - 摘要：The conversing of intelligent optical networks with P2 MP technology will greatly promote the development of optical multicast services.This paper proposes a hierarchical Path Calculation Element（PCE）-based Multi-Domain Minimum-cost Path Heuristic（MDMPH）algorithm and conducts the related simulation and analysis.Compared with the traditional Per-Domain Based（PDB）algorithm,Extended-BRPC（E-BRPC）-based algorithm and Core Tree Based（CTB）algorithm,MDMPH algorithm can calculate a smaller cost P2 MP path tree.
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发布时间： - 摘要：This paper proposes a novel integrated broadband access network architecture on the basis of analyzing the relevant research status of the Software Defined Networks（SDN）at home and abroad.In compliance with the OpenFlow protocol,this architecture realizes the intelligent management and control of optical-wireless access networks,effectively implements the relevant resource allotment algorithm,routing selection protocol and energy-saving mechanism and enhance the network performances.关键词：SDN;optical-wireless access network;Openflow protocol;intelligent management and control
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发布时间： - 摘要：This paper first studies the impacts of extraction and interpolation on signal spectrum in multirate signal processing.Then it theoretically derives the signal spectrum after integer times extraction and integer times zero-value interpolation by using the Fourier Transformation（FT）,obtaining the regular pattern of signal spectrum after extraction and interpolation as well as the method for avoiding spectrum aliasing.In addition,it analyzes it in experimental simulation,verifying the correctness of the theoretical derivation.Finally it presents a few points for attention in multirate signal processing.关键词：multirate signal processing;extraction;interpolation;spectrum;FT
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发布时间： - 摘要：With the rapid development of communication technologies,how to realize a low-cost high-capacity transmission of information in limited bandwidth has caused widespread concern.This paper describes the design of an Intensity Modulation/Direct Detection（IM/DD）and Orthogonal Frequency Division Multiplexing（OFDM）-based transmission system over 40 km Standard Single-Mode Fibers（SSMF）,which uses a 10Gbit/s class Electro-absorption Modulated Laser（EML）and an Avalanche PhotoDiode（APD）.It realizes the related algorithms using MATLAB programming software,simulates the system by using VPI simulation software and analyzes the experimental results,which verify the feasibility of applications of the OFDM technology to future low-cost high-rate optical communication systems.关键词：OFDM;EML;APD;MATLAB software;VPI software
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发布时间： - 摘要：Fiber-optic communication is the most important transmission means for power line protection and signal control.By now there is not yet any case of the commercial operation of Remote Optical Pump Amplifier（ROPA）system in China’s electric power grids and so no design experience,therefore it is a research subject to be urgently enhanced to design a reliable ultralong-distance ROPA fiber-optic circuit for electric power system communication.This thesis introduces the basic principle of the ROPA technology,presents a ROPA system scheme adoptable in practical project and analyzes this scheme in connection with practical project cases.The proposed design method can be used as important reference for the discussed system design.关键词：ultra-long-distance transmission system;ROPA;RPU;Er-doped fiber;Raman amplifier
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发布时间： - 摘要：The intelligent Optical Distribution Network（ODN）technology applies the electronic tag technology to the traditional ODN and identifies the resources at the Optical Distribution Frame（ODF）device port by using the electronic tags.This paper presents a novel electronic tag-based fiber ring technology,which is used to identify the uniqueness of fibers and has the advantages of easy reading,stability and high efficiency.The system realizes automatic fiber information storage and uploading,correct fiber-MUMM connection monitoring and fiber resource information calibration,thus solving the technical problems of intelligent ODN.关键词：ODN;ring;electronic tags
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发布时间： - 摘要：<正>近日,烽火通信自主研制开发的"10Gbit/s EPON智能家庭网关设备",获得2014年度国家科技部重点新产品计划立项,这是东湖新技术开发区首推入选国家重点新产品的企业,也是近年来烽火通信第三次入选国家重点新产品计划。烽火通信始终坚持以市场为导向,以创新促发展,非常重视科技创新与技术引领,面对通信行业技术转型的趋势,烽火通信抓住机遇,集中优势资源投入到10Gbit/s EPON智能家庭网关设备设备的研发中,申
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发布时间： - 摘要：<正>随着光纤市场竞争的日趋激烈,光纤的单位产出效率越来越成为各大光纤厂商关注的焦点。以拉丝速度为例,如果拉丝速度从2 000m/min提升到2 500m/min,则单位产出效率将提升20%以上。这样不仅可以带来整体产能的提升,而且可以有效降低单位产出的分摊费用,从而降低光纤的成本,提升产品的竞争能力。因此,对于光纤厂商而言,通过进一步挖掘光纤技术潜力,提升光纤制造设备的性能,从而提升光纤产能
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发布时间： - 摘要：<正>7月28日中国企业联合会公布了2014年中国制造业500强的排名,武汉邮电科学研究院获得了第295名,较去年302位的排名前进了7位。中国制造业500强的排名主要依据企业的营收情况,武汉邮电科学研究院去年营业收入达到186亿元,较前年增长幅度较大。2013年三大运营商共进行四次100G干线招标,武汉邮科院（烽火科技集团）全部中标,市场份额超30%;光缆产品在三大运营商集采中均取得前三名,武汉邮科院（烽火科技集团）已成为三大运营商核心供应商。IPRAN产品成功跻身国内运营商主流供应商行列,PON系列产品在三大运营商集采中均处前两位,家
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发布时间： - 摘要：To determine the value range of Brillouin shift in multimode fibers and evaluate the performances of Brillouin scattering-based distributed sensing system,this paper first describes the fiber structures and analyzes the Brillouin scattering process in them on the basis of ray optics theory.Then it proposes a method for determining the value range of Brillouin scattering angle.In this method,it determines that the Brillouin scattering angle in step-index and graded-index multimode fibers is in the range of twice of the critical angle of total reflection toπ,and that the Brillouin shift varies in the range of 10.97811.083 GHz.This conclusion provides a forceful theoretical basis for the design and optimization of the distributed Brillouin sensing system for multimode fibers.关键词：distributed sensing;Brillouin scattering;multimode fiber;scattering angle;Brillouin shift
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发布时间： - 摘要：In order to improve the magnetic detection technology for submarine optical fiber cables,this paper first analyzes the main structure of submarine cables and anchors and establishes a mathematical model of anchor hooked submarine cable.Then,it simulates the features of the magnetic field around the hooking point by using MATLAB,calculates the maximum magnetic induction intensity in different detection ranges and provides a theoretical basis for improving the efficiency in submarine cable detection.关键词：submarine optical fiber cable;anchor;detection
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发布时间： - 摘要：This paper studies the Brillouin shift variations of fibers in Optical Fiber Composite Overhead Ground Wire（OPGW）cables by using the BOTDR technology on the basis of the Brillouin scattering principle.The experimental results show that the temperature coefficients of Brillouin Scattering（BS）shifts of different fibers in the same cable are slightly different from those of the basic frequency shifts,while there is a fairly constant difference in temperature coefficients between fibers in the sunshine zones and those in the shadowy zones.关键词：OPGW;sensor;Brillouin frequency shift;temperature coefficient
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发布时间： - 摘要：This paper introduces the applications of parts of new technologies in OPGW in recent years,including optical fiber sensing technology in temperature measurement and in-line stress monitoring,new ice-melting technology and a new type of optical fiber with an external diameter of 200μm and OPGW with large excess-length optical fiber.In addition,,it predicts the trend of technological applications in OPGW cables.关键词：OPGW;optical fiber sensing;ground wire ice-melting;200μm-diameter optical fiber;large excess-fiber length OPGW cable
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发布时间： - 摘要：This paper studies in depth the losses resulted from the mechanical alignment errors in fiber-optic information transmissions at 1 550 nm and 1 310 nm.MATLAB simulation results show that attenuation in higher order modes is more serious than that in lower order modes and the lateral alignment error of single-mode fibers is the most serious factor for these losses,and that when the Numerical Aperture（NA）is large,the coupling loss caused by angle deviation is reduced,while when the NA remains the same,the higher the refractive index of matching fluid,the lower the coupling efficiency,which is opposite to the effect on losses arising from the end clearance.The study results in this paper have certain theoretical and practical significance for the stable development of fiber-optic information communication.关键词：fiber-optic transmission;infrared wavelength;propagation mode;mechanical error;loss
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发布时间： - 摘要：In the light of the rigorous coupled wave theory and equivalent medium theory,this paper presents the structure of and design method for GaN-based subwavelength guided-mode resonant grating filters for C band of optical communications and discusses in detail the effects of grating period and incident angle on the resonant wavelength of the filter reflectance spectrum under the actions of high duty cycle of strongly modulated grating.While keeping the filtering effects as high diffraction efficiency（resonant wavelength peak reflectivity above 99.5%）,low sideband reflection and narrow linewidth,it uses its sensitivity to the incident angle and in combination with the numerical simulation presents a method for tuning the incident angle（04.07°）by a MEWS planar reflector,thus linearly controlling the resonant wavelength output in a tuning range of 36 nm and realizing a tunable filter with FWHM lower than 0.8nm for C band of optical communication networks.关键词：guided-mode resonance;GaN;filter;MEMS
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发布时间： - 摘要：This paper proposes and studies a linear-cavity-structured passively Q-switched Bragg fiber grating Er-doped fiber laser using a Semiconductor Saturable Absorber Mirror（SESAM）.This laser controls the polarization state of laser without the need to use a polarization controller,thus simplifying its structure.Its central wavelength is 1 549.975 nm,threshold power143 mW and slope efficiency 1.2%.When the pump power is increased from 149 mW to 180 mW,the pulse repetition frequency obtained can be increased from 5.431 kHz to 9.778 kHz.When the pump power is 155 mW,the fiber pulse energy is 5.6nJ and the pulse width is 40μs with a repetition frequency of 6.538 kHz.关键词：fiber laser;passively Q-switching;SESAM;Bragg fiber grating
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发布时间： - 摘要：In the smart grid,current measurement is the key to relay protection,energy metering,monitoring and system analysis in the electric power system and the measurement accuracy and reliability are directly related to its safe,reliable and economical operation.This paper compares the performances of the electromagnetic current sensors and fiber-optic current sensors and introduces the measuring principles of 3kinds of major ones and points out their advantages and existing problems.Then,it summarizes their latest research status and advances at home and abroad.Finally,it forecasts the prospects of their applications and researches.关键词：fiber-optic current sensor;Rogowski coil;fiber Bragg grating;Sagnac interferometer;birefringence effect
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发布时间： - 摘要：In video transmissions over Ad Hoc networks,packet loss rate of the video stream is a key factor affecting the video transmission quality.The traditional AODV routing protocol depends itself solely on such information as the number of hops in RREP messages for routing updates,easily leading to network load imbalance,increasing the packet loss rate of video frames and causing unclear video images.The proposed V-AODV protocol select the routes on the basis of the load status and hop number to avoid heavy load nodes,enabling balanced load in the entire video network.This paper simulates the video stream transmissions under the V-AODV and AODV protocols respectively using NS2 and compares them thereafter.The results indicate that V-AODV reduces the packet loss rate of video frames and effectively realizes load balance in video transmissions.关键词：Ad Hoc;video transmission;load balancing;AODV
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发布时间： - 摘要：This article introduces a multi-point cooperation-based uplink resource scheduling method in four aspects:decision of cell edge users and cell center users;selection of radio resource allocation modes,antenna setting and received data processing and system simulation.It emphatically analyzes the user division standard setting,and resource allocation,frequency selection measure setting of frequency selection mode and joint received data processing in the multi-point cooperation mode.Simulation results show that by rationally setting and adjusting the system control parameters,multi-point cooperation can effectively reduce the system bite error rate and improve the system throughput.
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发布时间： - 摘要：This paper adopts Turbo code that has excellent error-correction performance in UV communications and simulates the atmospheric turbulences in the channels by using agamma-gamma turbulence model.Considering the Pulse Position Modulation（PPM）mode commonly used in UV communications and the effects of turbulence,it analyzes the variations of such factors as the refractive rate structural constant and wavelength on Turbo code performances.Simulation results reveal that under the same conditions,the smaller the structural constant and the longer the wavelength,the better performance the Turbo code will achieve.This conclusion provides a theoretical reference for its practical implementation.关键词：UV;atmospheric turbulence;Turbo code
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发布时间： - 摘要：<正>科技论文的引言是简要说明研究的主要目的、范围,即为什么写这篇论文以及要解决什么问题;前人在本课题相关领域内所做的工作和尚存的知识空白,作简要的历史回顾和现在国内外情况的横向比较;研究的理论基础、技术路线、实验方法和手段,以及选择特定意见方法的理由;预期研究结果及意义。引言部分一般分为三到四个层次:（1）由研究背景、意义、发展状况等内容组成,其中还包
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发布时间： -
- 摘要：<正>企业概况成都新易盛通信技术股份有限公司成立于2008年,是拥有多型号产品的专业光模块制造商和技术服务提供商,自设立以来一直专注于光模块的研发、生产和销售。目前,公司产品型号超过2,800种,产品覆盖数据宽带、电信通讯、FTTx、数据屮心、云计算、安防监控和智能电网等多个行业领域,产品销往全球超过60个国家和地区。公司高度重视新技术和新产品研发,坚持以市场为导向的研发理
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