华为Smart Test宽带线路测试解决方案

ADSL接入技术是目前发展最快的一种宽带技术,随着宽带网络规模的逐步扩大,在ADSL建设中线路测试和远端维护的重要性日渐突出。华为公司袁千先生的《华为Smart Test宽带线路测试解决方案》一文结合目前ADSL网络建设的实际问题,详细介绍了华为公司Smart Test宽带测试的方案、功能和测试方法,具有很强的实用性。本文提出的宽带测试方案已经获得了商业应用,缓解了ADSL运营中维护的压力,对各运营商开展ADSL接入,解决实际网络问题具有很高 的参考价值。     

非对称数字用户线路性能的在线测试方法

在各种宽带接入技术中,具有代表意义的一种技术就是在双绞线上开通的ADSL(非对称数字用户线路)。在宽带系统的运行和维护中,ADSL的在线测试技术是承担故障定位、故障诊断的关键环节。介绍影响双绞线性能的主要外界因素以及几种在线测试的方案并重点探讨测试模块嵌入DSLAM的方法。     

烽火通信宽带测试解决方案

当前，ADSL业务已经成为运营商发展宽带用户的一项主流技术，中国已经成为全球ADSL应用增长最快的市场之一。到2003年底，中国ADSL市场规模已经超过1000万线，占全球整个ADSL用户数的40％。同时，运营商DSLAM网络规模的扩大，给运营商带来了新的维护和管理压力。比如在ADSL开通时会面临如何选择线路，线路能否开通业务，开通的速率是多少等问题；在ADSL电路的日常维护中经常遇到障碍查找．判断和排除等问题。这些都需要对ADSL线路进行测试，而原有的112窄带测试系统却不能满足需求。本文在分析ADSL规模应用所面临的各种问题之后，着重介绍如何在烽火通信的FreeLink AN2200—01设备上快速．有效地实现宽带线路的测试。     

GTS通用112线路测试系统原理及常见问题分析

随着中国电信改革的不断深入,用户对电信服务质量提出了更高要求,其中112线路维护障碍检修是电信服务的重要一环。速度快、测试准、功能全的线路测试设备对提高电信公司的运行维护服务水平有着极大的帮助。最近,由上海欣泰通信技术公司提供的GTS通用112线路测试系统已在北京电信公司顺利开通。     

华为Smart Test宽带线路测试解决方案

第三届中国电信"宽带极速之旅"的启动,成为2003年宽带步入更高速度发展的标志.以中国电信集团为例,其宽带用户在2002年新增98.2万,同比增长247.4%,其中ADSL建设已经成为宽带接入的主流模式.随着DSLAM网络规模的扩大,由于缺乏完善的维测手段,网络维护管理的压力越来越大,急需解决宽带线路测试和终端管理维护等问题.     

英飞凌推出多信道线路测试解决方案

英飞凌科技股份公司近日在世界宽带论坛上展出专为XDSL接入设备提供综合线路测试的全新芯片组。这种设计独特、经济划算、性能可靠的多信道金属线路测试（MLT）解决方案，具备内置“湿性电流”功能，可提供先进的线路和回路测试功能，实时监控语音质量和网络的稳定性。     

一种新型的ADSL线路测试系统

随着Internet的商业应用和多媒体等服务的迅猛推广,能够为用户实现入网的数字化、宽带化的ADSL宽带接入技术得到了广泛应用,并在未来一段时间内仍将占主导地位。但是,在ADSL用户迅速增长的同时,用户故障申诉也在大幅度增加。在这些用户故障中,线路故障占了相当大的     

ADSL维护测试系统应用问题的探讨

近年来，随着ADSL用户数量的不断增加．接入网络快速扩大．运行设备和线路的维护与管理问题日渐突出。如何建立ADSL宽带维护测试与管理系统，形成建设、运营维护和管理相结合的ADSL宽带产业链．提高ADSL宽带业务的服务质量．已成为各地电信运营商关注的问题。     

数字电力线路传输综合信息网

数字电力线路(简称DPL)传输综合信息网是用电力线路传输电话、计算机数据、数字广播电视等的网络。数字电力线路是电力线路在传输电力能源的同时又传输数字信息,为一线两用技术。现代计算机网络发展,要求将宽带信息接入用户。采用光缆线路使宽带入户,技术上固然可以实现:但存在造价高、建设时间长等问题。于是出现了各种宽带接入网,如XDSL,Cable modem,宽带光缆,     

全球宽带接入市场发展分析分析

通过对目前宽带线路数最多的10个国家和地区、2003年上半年新增线路最多的10个国家、全球宽带业务普及率最高的10个国家和地区、部分运营商住宅DSL业务的第一年费用以及2000～2002年全球入门级住宅DSL业务价格的发展趋势等图表的分析,阐明了全球宽带接入市场的发展状况,指出了其市场规模继续扩大、经济发达国家宽带线路增长速度较快、普及率的差距逐渐缩小以及业务价格趋于稳定等特点.     

版图图形特征对铜化学研磨的影响

Copper chemical mechanical polishing （CMP） is influenced by geometric characteristics such as line width and pattern density, as well as by the more obvious parameters such as slurry chemistry, pad type, polishing pressure and rotational speed. Variations in the copper thickness across each die and across the wafer can impact the circuit performance and reduce the yield. In this paper, we propose a modeling method to simulate the polishing behavior as a function of layout pattern factors. Under the same process conditions, the pattern density, the line width and the line spacing have a strong influence on copper dishing, dielectric erosion and topography. The test results showed： the wider the copper line or the spacing, the higher the copper dishing; the higher the density, the higher the dielectric erosion; the dishing and erosion increase slowly as a function of increasing density and go into saturation when the density is more than 0.7.     

Effects of pattern characteristics on copper CMP

Copper chemical mechanical polishing(CMP)is influenced by geometric characteristics such as line width and pattern density,as well as by the more obvious parameters such as slurry chemistry,pad type,polishing pressure and rotational speed.Variadons in the copper thickness across each die and across the wafer Can impact the circuit performance and reduce the yield.In this paper,we propose a modeling method to simulate the polishing behavior as a function of layout pattern factors.Under the same process conditions,the pattern density,the line width and the line spacing have a strong influence on copper dishing,dielectric erosion and topography.The test results showed:the wider the copper line or the spacing,the higher the copper dishing;the higher the density,the higher the dielectric erosion;the dishing and erosion increase slowly as a function of increasing density and go into saturation when the density is more than 0.7.     

Spectral filtering criteria for U-band test light for in-service line monitoring in optical fiber networks

In the fiber-to-the-home era, thousands of optical fibers will have to be accommodated in the central offices of optical access networks. To reduce maintenance costs and improve the service reliability of optical fiber networks, the authors must develop an optical fiber line testing system with a function for in-service line monitoring that uses a test light with a wavelength different from the communication light wavelength. To monitor an in-service line in an optical network, the effective rejection ratio of the test light must be taken into account. This ratio depends on the spectrum of the test light from the optical time-domain reflectometer and the rejection band of the filter in front of the optical network unit. The dependence of the effective rejection ratio as a function of the sideband suppression ratio (SBSR) and of the ratio of the rejection band to the bandwidth of the sideband noise d/D is clarified. When d/D=0.1 and the target effective rejection ratio of the filter is -40 dB, the SBSR and the filter loss of the termination cable must be -70 and -43 dB, respectively, or the SBSR must be -80 dB. When d/D<0.5 and the target effective rejection ratio of the filter is -40 dB, the SBSR is also required to be -80 dB. In-service line monitoring for a 10-Gb/s transmission using a 1650-nm test light with an SBSR of -80 dB is also demonstrated.     

SMT焊管印刷质量自动光学检测

本文主要论述了自动光学检测（AOI）在SMT生产线的重要作用，以及焊膏印刷的检测技术和质量控制意义。通过焊膏印刷质量的检测，提高最终在线检测或功能检测的合格率，降低返修成本。     

星载高可靠裸芯片设计*

通过研究裸芯片的可靠性保证技术,提出了集成的已知良好芯片(KGD鄄确优裸片)的可靠性保证指南,并制定了完善的裸芯片设计、生产、过程控制和可靠性评估等技术流程。文章确定了KGD 的规范线,作为裸芯片可靠性测试的检验标准。根据KGD 规范线对裸芯片进行全频测试,并进行3MHz 老化试验。通过试验,可以确保KGD 的可靠性指标达到IC 封装的要求,最终实现使用裸芯片的星载电子装备小型化、轻量化、高可靠、多功能和低成本。     

Subscriber Line Equipment for an Elastic Carrier Switching System

This is the third of three papers [l], [2] dealing with an elastic carrier-concentrator system. The functioning of the subscriber line equipment is described herein. The system serves 256 telephone subscriber lines by digital concentration switching and transmission of multiplexed message channels over a singleT1transmission line. The concentration switching function is nonblocking. Message channels are the individual communication links between terminals and are created on demand at the request of active subscriber lines. They are not merely inactive without service requests; they do not exist unless service is requested. The created message channels serve for their normal communication function and, in addition, carry for each line the ancillary functions of dialing, ringing, and pay-station coin disposal. Message channels are coded by delta modulation, which permits flexible digital concentration and provides a smooth tradeoff of channel quality versus the instantaneous traffic load. Each of two complementary subscriber line interface units, one per line at each end, provides the delta-modulation encoding and decoding functions for the analog voice-band signal input and output and, by overriding the delta codec, provides the desired signaling functions of dialing, ringing, etc. The line interface units provide the major equipment interface between the subscriber line and the digitalT1line. An integral test facility permits remote loop-back of any selected subscriber line unit via a test channel to the office terminals and at the same time connects the subscriber loop to an auxiliary programmed test facility which may transmit pertinent loop-test results to the office terminal.     

安规测试系统的设计分析

介绍了安规测试系统的结构组成及功能实现。该系统的设计可减少测试工位以提高工作效率。使管理者实时了解生产状态,并能对生产线±：所有检测数据自动编码存储分析．数据自动上传公司服务器或商检局系统。     

A new test method for contactless quantitative current measurement via scanning magneto-resistive probe microscopy

The aim of this paper is to present a new test method for contactless quantitative current measurements via scanning magneto-resistive probe microscopy. Its basic principle is based on the detection of the magnetic field over a current-carrying conducting line by a magneto-resistive probe, which is fastened to a canning orce icroscope (SFM). The function and efficiency of this method is demonstrated by measuring the current flow through a conducting line with hundred kilohertz bandwidth. Regarding to the function and failure analysis of integrated circuits the size of the magneto-resistive probe is reduced, and the obtained experimental results are discussed.     

基于GL0816传感器的高速线阵CMOS相机系统设计

为了满足印刷等高端工业检测中物体快速运动,需要大幅面、高行频、高分辨率图像采集等要求,研发了一款微米级高分辨率、高速线阵工业相机。首先,介绍了高行频、高分辨率国产CMOS图像传感器GL0816的功能与特点。然后,基于该芯片设计了一套高速大幅面高分辨率线阵工业相机系统,该系统采用FPGA作为整个系统的控制核心,以DDR3LSDRAM作为图像缓存器,以GigE vision2.0协议为输出标准,以SFP+作为高速图像输出接口。最后,搭建相机系统测试环境,对所设计的相机进行系统测试。结果表明:该相机系统行分辨率为8 192,可连续采集2 000行作为一帧图像输出,行频为50kHz,动态范围为57.32dB,信噪比为40.95dB,具有实时图像采集功能。该相机系统具有大幅面、高帧频、高分辨率、高信噪比、宽动态范围等优点,适用于印刷检测行业快速运动目标捕获成像及图像实时显示。     

Automated Test Equipment for Phased-Array Modules

A computer-controlled production test system for air-borne phased-array microwave modules is described. In the transmit mode accurate measurements of module output power and phase as a function of input power and frequency are made automatically on a pulse basis, and with 4:1 frequency translation from module input to output. Module receiver gain, IF output phase, and noise figure are measured as a function of frequency and local oscillator input power in the receive mode. Other measurements under computer control include dc levels, input and output VSWRS, gain compression, output pulse characteristics, spurious levels, and spectral purity. All test parameters are automatically compared to unit-specification limits as well as reference-standard (unit-to-unit) limits. The system errors are measured periodically through use of calibration standards, stored in memory, and applied as corrections to the measured data on the module under test. Input power, derived from a coherent microwave synthesizer, is automatically adjusted to the required level prior to each test. All test data are recorded on magnetic tape and available to the operator by means of a line printer when desired. The module test fixture incorporates precision (APC)-7 to module adapters, dc connections, an array simulator, and temperature control.