窄带ISDN设备协议测试

使用惠普公司ＰＴ５００协议测试仪，可以有效地完成交换设备中窄带ＩＳＤＮ ＤＳＳ１协议的一致性测试。文章从用户侧和网络侧设备ＤＳＳ１协议测试，对分组接入能力的测度以及配置合物理层测试等几个方面介绍了ＰＴ５００协议测试仪的使用方式和不同配置情况。     

走在世界前列的测试设备制造商——ADVANTEST公司

走在世界前列的测试设备制造商——ＡＤＶＡＮＴＥＳＴ公司走在世界前列的测试设备制造商———ＡＤＶＡＮＴＥＳＴ公司１概况日本ＡＤＶＡＮＴＥＳＴ公司，原名ＴａｋｅｄａＲｉｋｅｎＩｎｄｕｓｔｒｙ有限公司，于１９５４年成立。创办人ＩｋｕｏＴａｋｅｄａ。１９８５...     

DAC和ADC精度校准与测试技术

文章从实践角度叙述了ＤＡＣ和ＡＤＣ的精度校准与测试技术。这种测试技术所需设备少，简便快速，实用性强。     

SDH虚拟实验在远程教学上的运用

介绍了虚拟实验在远程教学中的意义以及ＳＤＨ网络系统所包含的虚拟测试实验项目，重点以测试ＳＤＨ平均发送光功率为例详细介绍了ＳＤＨ设备虚拟实验在远程教学中的实现过程。     

DACSⅡ数字交叉连接设备

ＤＡＣＳⅡ数字交叉连接设备作为数字数据网主要组成部分的数字交叉连接设备，最近有ＤＡＣＳⅡ新产品面市。该设备采用单时隙交换结构，以高速局域网处理方式和分布处理方式，确保在极短时间内对任意数量６４ｋｂ／ｓ线路（ＤＳＯ）的处理均无阻塞，并为任一通道提供测试...     

红外扫描探测系统综合性能描述和测试方法的研究

以系统输出信噪比为判据，建立了系统的作用距离Ｒ，最小可分辩温差ＭＲＴＤ，最小可探测温差ＭＤＴＤ与系统的噪声等效温差ＮＥＴＤ和调制传递函数Ｈｓ之间的关系；并研究了这些性能参数的测量方法，为系统综合性能评估和性能测试提供了依据。     

GTEM辐射发射自动测试系统

本课题应用ＧＴＥＭ室作为ＤＵＴ辐射发射的测试设备，使本自动测试系统具有效率高，成本低，测试频率宽的特点。ＤＵＴ在ＧＴＥＭ室内的辐射发射测试结果经理论计算，可转化为开阔场地的场强值，本系统可完成基于ＧＪＢ１５１－１５２标准的有关测试。     

广播电视SDH光传输设备及其测试

ＳＤ贞步数字传输设备通常也称之为ＳＤＨ网元，包括终端复用器，再生中继器１、分插复用器和同步数字交叉连接设备等。设备测试包括光接口、电接口、拌动和源移特性、误码性能、定时与同步和设备功能以及网管系统配置、功能和接口。     

保持系统最佳性能的同时延长电池寿命并且降低功耗的设计难题

远离工作现场的测试系统既要求便携式测试设备高性能工作又要延长电池寿命。此外，数字式超声系 统有２５６～５１２个反射信号通道，每个通道的ＡＤＣ都要求功耗最低的同时保持最佳的动态性能。ＡＤＩ 公司提供的ＡＤＣ可以解决这项设计难题。     

光测试设备市场形势喜人

Ｆｒｏｓｔ＆Ｓｕｌｌｉｖａｎ公司最近出具的一份题为“世界光测试设备市场分析”的报告指出，由于消费者和业务交往对互联网快速、宽带连接需求的激增，通信公司将安装更多的光技术产品以应对这些挑战。因而，光测试设备市场将随之迅速膨胀，由２０００年１４．２亿美元的水平攀升到２００７年的６０亿美元。 Ｆｒｏｓｔ＆Ｓｕｌｌｉｖａｎ产业分析师Ｂａｌ Ｇａｎｊｏｏ认为，ＤＷＤＭ技术的广泛应用对光测试设备市场有着巨大的促进作用。 Ｇａｎｊｏｏ指出，测试设备供应商应该不断提供升级产品，以适应日渐复杂的新技术测试环境以及相…     

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.     

Quantum theory analysis of the action micromechanism exerted on bioparticles from laser microbeams

The effect of laser microbeam trapping the bioparticles has been appfied widely in the biology .However the micromechanism of the acting that realizes the laser-microbeam trapping bioparticles is still lacking. In this paper ,the act microchenism of the gradiant force of laser microbeam for the bioparticles is analysed by means of quantum theory ,The result accords with our experiment.