Ethernet over SDH技术的原理及应用

EOS结合了SDH和以太网两大技术的优势,在全世界通信网向IP网络统一的过程中,即可以保护现有网络投资,又可以扩展以太网的传输距离。详细阐述了EOS技术的原理,分析了EOS技术的优势,并给出了采用EOS设备组网的例子。     

信息速览

新品|支持8K 60P RAW机内记录佳能发布数字电影摄影机EOS R5 C2022年2月24日,佳能(中国)有限公司宣布推出数字电影摄影机新品EOS R5 C。佳能EOS R5 C数字电影摄影机是佳能Cinema EOS系统家族新成员,融合了Cinema EOS数字电影机和EOS R全画幅专微系列的优势功能。EOS R5 C沿用了EOS R5高达约4500万像素的全画幅CMOS图像感应器和DIGIC X影像处理器,不仅具有与EOS R5几乎相同的高规格拍照性能。     

观察世界的眼睛：佳能数码相机系列发展史——EOS D

EOS D系列是可换镜头的单镜头反光数码相机．该系列相机采用传统单反相机的机身．支持EF型镜头．支持专业EX系列外置闪光灯。目前有六位成员，它们是EOS D2000、EOS D30、EOS lD、EOS D60、ECS lDs以及EOS 10D。其中EOS D30、EOS D60、EOS 10D是“亲父子”的关系，生产主旨是：性能一流，价格低廉，面对的是专业里的低端用户。EOS 1D和EOS 1Ds主旨思想是：最好，是专业级里的专业级。     

新品|支持8K 60P RAW机内记录佳能发布数字电影摄影机EOS R5 C

2022年2月24日,佳能(中国)有限公司宣布推出数字电影摄影机新品EOS R5 C.佳能EOS R5 C数字电影摄影机是佳能Cinema EOS系统家族新成员,融合了Cinema EOS数字电影机和EOS R全画幅专微系列的优势功能.EOS R5 C沿用了EOS R5高达约4500万像素的全画幅CMOS图像感应器和D...     

MAPOS协议在EOS组网中的应用

对实现 SDH上传送以太网数据的相关协议进行了探讨 ,提出现有 EOS设备在组网能力上的不足 ,并通过对 MAPOS协议的研究 ,阐明 MAPOS协议实现 EOS组网的原理 ;最后针对 EOS的现状提出如何利用 MA-POS扩展现有 EOS设备组网能力的方法     

CANON EOS 30D——单反新主角

每18个月推出一款新的单反已经不是什么秘密了。从年初开始，EOS20D就开始清仓甩卖，此时关于EOS20D的升级产品也被各种猜测炒得沸沸扬扬。EOS30D的指标到底是什么样子的。是不是能超越之前Nikon推出的D200，成了许多用户和摄髟爱好者最为关注的事情。2月21日，佳能在全球发布了这款被命名为EOS30D的产品。但出乎我们预料的是，这款产品只是EOS20D的小升级版本，在性能指标方面也仅仅是略有改善。那么这款相机的意义是什么呢？是单纯取代EOS20D的市场空间，还是另有图谋？     

MAPOS协议在EOS组网中的应用

对实现SDH上传送以太网数据的相关协议进行了探讨，提出现有EOS设备在组网能力上的不足，并通过对MAPOS协议的研究，阐明MAPOS协议实现EOS组网的原理；最后针对EOS的现状提出如何利用MAPOS扩展现有EOS设备组网能力的方法。     

SDH系统上以太网传送技术的研究

研究了SDH系统上的以太网传送技术——EOS,阐述并分析了EOS的核心技术LAPS和GFP协议,详细描述了它的特点和应用并把它们与POS技术进行了对比。     

EOS业务的配置及原子功能模型研究

EOS(Ethernet Over SDH)是EOT(Ethernet Over Transport)中的一部分,是ITU-T对MSTP上的以太网业务进行描述时采用的术语。对于相同的EOS业务需求,可以有多种部署方式及实现方式。利用EOS设备的原子功能模型对典型集团专线业务的实现方式进行了描述,分析了相应的配置流程,并进行了简单的比较。     

克服放大器电气过应力问题（上）

当一个系统有多个电源时,可能出现运放电压输入高于电源轨的电气过应力(EOS)问题。通常工程师在考虑过应力时,常会想到静电放电(ESD),而EOS往往被忽略。本文介绍了EOS状态及解决此问题的方法。     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

避免MOS管在测试时受EOS损坏的方法

由于MOS管是浅结系列产品,极有可能在测试时遭到静电击穿或过压过流而损坏。文中主要介绍MOS管在测试过程中,会造成实际测试时器件加上了允许的最大电压、电流或功率而导致器件损坏的情况。例如,在测试过程中电源连接不良,测试片与器件接触不良,管脚接错,在测试程序中未设置正确的电压和电流钳位或DUT板损坏等。然后,针对此类现象的发生,提出了在测试过程中应采取的相应措施,从而有效地保证产品质量。     

一种改善LED背光亮度均匀性的新型反射膜研究

在LCD的LED背光腔体的底面设计了新型曲面形状及性能的反光膜,将扩散膜反射回灯腔底部的光重新反射回出光口以改善亮度均匀性能;在侧面设计了镜面反射膜,将位于LED矩阵边缘区域由LED射向灯腔侧壁的光反射重新射向出光口,增加了LED背光边缘区域的亮度,从而改善了背光边缘区域较暗的亮度不均匀状况.根据此类反射膜的设计完成了反射膜的制备,并应用于38 cm LED背光源样品.测试结果显示,设置反射膜的LED背光的亮度均匀性值为10.2%,明显优于未设置反射膜的值16.8%,亮度提高了29%左右,表明该种新型反射膜可以提高亮度并改善亮度均匀性.     

圆球微腔对水蒸汽的敏感特性仿真实验研究

研究了圆球微腔在水蒸汽传感中应用的可行性。通过测试在有/无水蒸汽的气室环境下,圆球微腔透射光谱的变化来对气室水蒸汽浓度情况进行传感测试。仿真实验结果显示:在有无水蒸汽干扰的条件下系统输出光强有明显的变化,即研制基于圆球微腔的传感器是可行的。     

位屏蔽多叉树搜索射频识别防碰撞算法

针对RFID树型防碰撞算法中时隙数多、数据通行量大等问题,提出了一种改进的多叉树防碰撞算法,阅读器准确检测碰撞位并向标签反馈碰撞位信息,标签对阅读器已知的ID位进行屏蔽,把ID号转换成连续碰撞的序列号.阅读器利用屏蔽位信息和标签返回的碰撞位编码信息,对标签进行分层分类搜索.通过对标签ID进行屏蔽,阅读器和标签间仅发送对方不知道的碰撞位信息.该算法减少了碰撞时隙和识别时隙,避免了空闲时隙,减少了阅读器和标签间的数据通信量.理论分析和仿真结果表明,该算法减少了系统的时隙总数和数据通信量,提高了阅读器的识别效率.     

Design and nonlinearity compensation of Fabry-Perot type tunable optical filters for dynamic strain sensing systems

The collected spectrum of the fiber Bragg grating （FBG） and the loss of the detected optical power are discussed with respect to the 3-dB bandwidth of a Fabry-Perot （F-P） type tunable optical filter （TOF）, respectively. And the optimized parameters of the TOF are obtained consequently. It is demonstrated that the relationship between the transmission wave- length of the TOF and its drive voltage is nonlinear. A new method to compensate the nonlinearity of the TOF is proposed. The linear sweeping of the transmission wavelength of the TOF is achieved through modifying the drive voltage using interpolation algorithm. It is observed that the average error and the maximum error of the transmission wavelength are reduced sharply under linear fit. The dynamic strain sensing is realized by use of a reference FBG and moving averaging algorithm in this system.     

Characteristics of gradually doped LWIR diodes by hydrogenation

The hydrogenation effects on HgCdTe diode performance are presented and the mechanism of hydrogenation is revealed. By the hydrogenation, R₀A is increased by 30 times and photo-response is also improved. It is supposed that these are explained by the increased minority carrier lifetime by the hydrogenation. However, it is found from LBIC measurements that the minority carrier lifetime doesn’t increase by the hydrogenation. An important clue that explains the hydrogenation effects is found from Hall measurements. It is found that, after the hydrogenation, the doping concentration of Hg-vacancy doped substrate decreases and the mobility increases. For the heavily hydrogenated bulk substrate, it is also found that the hydrogen passivates the whole Hg-vacancy and reveals the residual impurity and p-type doping concentration is exponentially graded. From these measurements, the diffusion current model of gradually doped diode is proposed. This model shows that the diffusion current of the graded junction diode is 2 orders of magnitude smaller than that of the abrupt junction diode, which clearly explains the R₀A increase by the hydrogenation. Medicisimulation to investigate the change of LBIC signal by the doping grading also coincides with the measurements. From these measurements and model, the hydrogenation effects are attributed to the grading of Hg-vacancy doped p-type substrate by the diffused hydrogen.