宽带业务和FTTx的发展现状与前景

1 前言 宽带技术自问世以来一直保持着蓬勃的发展势头.目前全球的宽带连接用户数已经突破3亿大关(见图1).据预测,各种宽带技术的用户数还将呈现不同速度的增长.另外,随着服务的多元化,各种宽带技术提供的带宽也将呈现不同幅度的增长.     

亨通光电FTTx整体方案助力运营商宽带战略

当前世界各国及地区纷纷着手推进宽带战略,FTTx不可避免的成为主要的承载方式,各国运营商将FTTx的建设作为重中之重。在各国政府及运营商的大力推进下,光通信行业受到了前所未有的关注。在这样的背景下,2012年中国国际光电博览会于9月6日在深圳召开,亨通光电依靠其独特的FTTH整体解决方案吸引了众多业内同仁的关注。     

FTTx推动我国信息化建设

我国电信运营商从2007年底开始的“光进铜退”战略,使我国光纤宽带接入FTTx得到快速的发展,从而进一步推动了宽带增值业务的发展。本文首先介绍国内外光纤接入的发展情况,然后分析宽带业务发展的主要驱动因素,及其对我国信息化建设的推动作用。     

日本FTTx快速发展

据预测，日本的FTTH用户数在2009年3月底将达到1575万户；2010年3月底将会达到1980万户；2011年3月末将达到2430万户。     

7342 ISAM FTTU——引领FTTx宽带光接入发展潮流

1 FTTx宽带光接入网络的发展是大势所趋 随着互联网和宽带应用的进一步发展,以"铜缆"为基础的电信网络必须逐渐向宽带多媒体架构转变.近几年来,运营商虽然已经在核心网和IP承载网进行了大量投资,但是以DSL技术为主的接入层仍然存在带宽瓶颈,大力发展FTTx宽带光接入网络已经成为全球运营商的共识.     

面向宽带提速的FTTx组网技术与应用

介绍了当前我国用户对带宽需求的现状，以及EPON和GPON技术的应用情况，为了进一步提升宽带网络的速度和应用安全性，更好地适应宽带业务发展的需求，结合现有网络资源，提出了针对传统宽带网络应用XPON技术，用光纤接入方式替代铜线接入方式的提速改造建议。     

基于面向宽带提速的FTTx组网技术与应用的研究

随着互联网技术的飞速发展,人们对宽带的需求也逐渐增长,传统的铜缆接入方式已无法满足宽带的发展需求。文章主要对GPON技术以及EPON技术进行了分析,提出将xPON技术应用于网络宽带中,对宽带进行优化,并采用光纤接入方式,进一步提高宽带的网速,确保网络的安全性。     

雷震洲：“大宽带”应列入国家发展战略

在去年的“两会”上,全国政协委员、工业和信息化部电信研究院科技委副主任雷震洲提出了为我国信息化战略冠名“i-China”的提案,建议我国将信息化战略展现给世界;今年,雷震洲提出了要把发展宽带提升为国家战略的提案,建议从国家层面制定战略措施,规划和推动宽带发展。连续两年关注信息宽带领域,体现了雷震洲对我国宽带发展的重视。     

湖北宽带发展接应国家战略的思考和建议

国家宽带战略是对网络空间规则体系主导权的争夺,是实现我国“十二五”规划提出经济社会发展目标的重要保障.从湖北自身具备的现实条件出发,分析了湖北宽带市场的行业背景、发展现状,并对湖北宽带发展接应国家宽带战略进行了深入思考,提出了适合湖北省自身经济发展和社会水平的具体建议.     

面向城镇的FTTx测算方法

通过建立合理的测算模型,利用家庭宽带现有接入数、现有FTTx端口储量、目标发展客户数和目标端口利用率和末端端口配比等参数,推算出家庭宽带新建端口规模以及覆盖家庭数。     

以FTTX实现三网融合的探讨

介绍了我国目前三网融合工作的计划和安排,分析了广电和电信运营商各自的现状和发展方向．提出了采用PON技术部署FTTx以实现三网融合的技术方案。     

ECU的功率管理,快速前进到42 V Powernet

本文将讨论汽车控制系统负载提供点(POL)调节功率所采用的技术，以及这些技术的优缺点。     

明确思路开拓创新全面推进海南无线电管理工作

无线电管理要适应社会主义市场经济的发展和我国加入WTO的新形势,与时俱进,开拓创新,坚持无线电管理服务于经济建设和社会信息化的大局。转变思想观念,改进管理方式,严格依法行政、依法管理频谱资源,充分发挥市场在配置频率和卫星轨道资源中的基础性作用,着力于建立公正、透明的法制环境,规范、高效的运行机制,先进、科学的管理手段。强化促进发展、保障安全、优化服务的意识,坚持有所为,有所不为,不断提高无线电     

Fast,Self‐Driven,Air‐Stable,and Broadband Photodetector Based on Vertically Aligned PtSe2/GaAs Heterojunction

Group‐10 layered transitional metal dichalcogenides including PtS₂, PtSe₂, and PtTe₂ are excellent potential candidates for optoelectronic devices due to their unique properties such as high carrier mobility, tunable bandgap, stability, and flexibility. Large‐area platinum diselenide (PtSe₂) with semiconducting characteristics is far scarcely investigated. Here, the development of a high‐performance photodetector based on vertically aligned PtSe₂‐GaAs heterojunction which exhibits a broadband sensitivity from deep ultraviolet to near‐infrared light, with peak sensitivity from 650 to 810 nm, is reported. The I_light/I_dark ratio and responsivity of photodetector are 3 × 10⁴ and 262 mA W^?1 measured at 808 nm under zero bias voltage. The response speed of τ_r/τ_f is 5.5/6.5 µs, which represents the best result achieved for Group‐10 TMDs based optoelectronic device thus far. According to first‐principle density functional theory, the broad photoresponse ranging from visible to near‐infrared region is associated with the semiconducting characteristics of PtSe₂ which has interstitial Se atoms within the PtSe₂ layers. It is also revealed that the PtSe₂/GaAs photodetector does not exhibit performance degradation after six weeks in air. The generality of the above good results suggests that the vertically aligned PtSe₂ is an ideal material for high‐performance optoelectronic systems in the future.     

Facet‐Dependent,Fast Response,and Broadband Photodetector Based on Highly Stable All‐Inorganic CsCu2I3 Single Crystal with 1D Electronic Structure

Low‐dimensional metal halides at molecular level, which feature strong quantum confinement effects from intrinsic structure, are emerging as ideal candidates in optoelectronic fields. However, developing stable and nontoxic metal halides still remains a great challenge. Herein, for the first time, high‐crystalline and highly stable CsCu₂I₃ single crystal, which is acquired by a low‐cost antisolvent vapor assisted method, is successfully developed to construct high‐speed (t_rise/t_decay = 0.19 ms/14.7 ms) and UV‐to‐visible broadband (300–700 nm) photodetector, outperforming most reported photodetectors based on individual all‐inorganic lead‐free metal halides. Intriguingly, facet‐dependent photoresponse is observed for CsCu₂I₃ single crystal, whose morphology consists of {010}, {110}, and {021} crystal planes. The on–off ratio of {010} crystal plane is higher than that of {110} crystal plane, mainly owing to lower dark current. Furthermore, photogenerated electrons are localized in twofold chains created by [CuI₄] tetrahedra, leading to relatively small effective mass and fast transport mobility along the 1D transport pathway. Anisotropic carrier transport characteristic is related to stronger confinement and higher electron density for {110} crystal planes. This work not only demonstrates the great potential of CsCu₂I₃ single crystal in high‐performance optoelectronics, but also gives insights into 1D electronic structure associated with fast photoresponse and high anisotropy.