城市光传送网WDM环网技术要求

介绍了WDM环网的主要技术,以及WDM环网在城市应用时应考虑的一些因素。 宽带城市网;;城市光传送网;;WDM环网;;波长转换器保护倒换子速率复用     

PCI-Express与ASI：避免在2Gbps速率上的混乱

在高达每路2Gbps的数据速率上，几乎没有什么技术能使信号完整性有很大的不同。哪种技术能真正提高性能？或者是只能使性能更差？专家们意见不一。     

CMTS数据网的用户速率与容量

文章所提出"折合户数"这一新概念,可在绕开网络运行随机性的条件下,来对网络进行速率和容量分析;阐明了单台256QAM状态的CMTS注册用户数以不超过600户为限的理论和计算依据。文中的分析方法和结论也适用于其它共享式数据网。     

10GbE成为主流

数年来，具有10Gbps速度的下一代以太网一直处于即将成为主流的状况。一段时间以来，网络的某些区域已在使用光学技术，并且随着流量的增加，对10GbE数据速率的需求正在增长。但是，需要一种比上一代以太网复杂许多的技术，用于在100m长的铜缆上运行10GbE。这一要求导致了昂贵的MAC（媒体访问控制器）和交换芯片，以及昂贵而又不方便的PHY层接口芯片，由此限制了快速LAN用于那些覆盖数据中心内较短距离的高性能应用。     

Realization of Tapered Waveguide by Stretching the Rod Waveguide

By stretching the rod waveguide with different velocities in opposite directions, the tapered waveguide can be fabricated. In condition of taking no account of volume expansion caused by heating and under the assumptions of volume conservation,the rod waveguide can be stretched freely in the heated region without being stretched outside of the heated region. A model,which shows the relation of the transition shape and the two factors, that is the ratio of two velocity and the heated region length, is presented for the shape of the taper transition through mathematic deduction. Based on this model, a desired tapered waveguide can be fabricated. The tapered waveguide are widely used for fabricating tapered fiber couplers and sensors. In addition, the conclusion can be used for fabricating fused fiber coupler.     

使用非单调技术的不精确预条件牛顿类方法解非线性方程组

本文提供了预条件不精确牛顿型方法结合非单调技术解光滑的非线性方程组．在合理的条件下证明了算法的整体收敛性．进一步，基于预条件收敛的性质，获得了算法的局部收敛速率，并指出如何选择势序列保证预条件不精确牛顿型的算法局部超线性收敛速率．     

Longitudinal leaky surface acoustic wave on Y-rotated cut quartz substrates

The properties of Quasi-longitudinal leaky surface acoustic wave(QLLSAW) on Y-rotated cut quartz substrates were presented. The phase velocity of QLLSAW on the quartz substrate along some orientations can be up from 6200 m/s to 7100 m/s, circa 100% above that of regular SAW. Both theoretical and experimental results show that QLLSAW propagating along some promising orientations for SAW devices are of small power flow angle and low tem-perature coefficient, for example, along the Euler angle (0°155.25°? 42°?, the measurements of phase velocity and temperature coefficient of delay of QLLSAW are 6201 m/s and 12.9 ppm/℃. The experimental results show that QLLSAW had little absorption by liquid loading on the substrate surface, which proved that the direction of particle motion is the same as wave vector and parallel to the surface of the substrates, i.e., the wave is of the properties of longitudinal wave.     

配合物氧化还原反应中的电子迁移轨道

研究了配合物氧化还原反应中的过渡态配合物结构 ,电子迁移轨道及反应速率。     

华为LTE 100Mbps无线速率领跑北京通信展

在日前举行的第16届中国国际通信设备技术展览会上,华为技术有限公司("华为")展示了全IP移动通信解决方案,并现场展示了超过100Mbps速率的高清电视和互动游戏等LTE(Long Term Evolution)业务。据了解,华为LTE基于全球领先的下一代多制式基站平台设计,将帮助运营商网络     

烽火通信实现单波2．5G速率超长距离稳定传输

日前，在中国南方电网组织的骨干传输网超长距离嗣试中，烽火通信智能光网络设备FonsWeaver780B实现了单蔽2．5G速率超长距离稳定传输，在长期性能监测中，系统运行稳定，各项指标优异。[第一段]