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1.
VLSIStructureforanAllDigitalReceiverforCDMAPABXHandsetZhouShidong;BiGuangguo(SoutheastUniversity,Nanjing210018)(Ph.Dstudentat...  相似文献   

2.
SPT推出CMOS单片高速A/D变换器系列SignalProcessingTechnologiesInc.(SPT)推出10位CMOS单片高速AD变换器系列。这一系列的速度从5MSPS到40MSPS。其中的5种产品分别是SPT7835(5MSPS),...  相似文献   

3.
ANovelVoiceCoderAt4800BPS(HSEV)WangXiaofengANDZhaoEryuan(DepartmentofTelecomrnunicationEngineering,BeijingUniversityofPosts&T...  相似文献   

4.
一、技求优势PACS(PersonalAccessCornmunicationSystem,个人接入通信系统)是由贝尔通讯研究室(Bellcore)基于美国WACS和日本PHS技术开发的数字微蜂窝个人移动通信系统。1996年PACS成为美国ANSI和ITU标准。美国联邦通信委员会也将PACS作为一种PCS系统加以推荐。与已成为地区标准的数字无绳电话系统DECT、PHS相比,PACS系统具有投资省、话音、数据质量好、服务功能全、系统容量大等特点。PACS充分利用了最新的DSP、计算机技术和信道编码…  相似文献   

5.
AXD4/1是爱立逊公司的传输网中新近投入使用的数字交叉连接系统(DXC-DigitalCrossConnect),是为满足同步数字系列(SDH-SynchronousDigitalHierarchy)和准同步数字系列(PDH-PiesiochronousDigitalHierarchy)传输网的多种需要而设计的。本文介绍AXD4/1系统的结构与组成。  相似文献   

6.
依靠技术革新PDP HDTV显示屏走向量产   总被引:1,自引:0,他引:1  
1998年开发出了新技术,1999年PDP(plasma display panel)的HD(high defini-tion)品种开始量产。富士通开发了新的驱动方法(ALIS(Alternate Lighting Surfaces Method)。这种方法将107cm(42″)显示屏的垂直象素由以往的480增加到1024,亮度也由300cd/m^2提高到500cd/m^2。这是PDP全彩色化以来  相似文献   

7.
ADI(Analog Devices)公司日前宣布将在中国举办“MotorintotheMillennium(新千年的电动机)”研讨会,介绍在电动机控制领域中,嵌入式DSP控制方案的优点。研讨会将介绍 ADI公司在电动机控制领域的技术专长,讨论嵌入式DSP电动机控制器的应用。研讨由Exdelpoint Systems)公司和AnalogDevices公司共同举办,日程安排如下: 北京2000年9月18日 上海 2000年9月 20日 深圳 2000年9月22日 研讨会将全面介绍AnalogDevices公…  相似文献   

8.
PECVDSiN及其在GaAsMESFET中的应用第Ⅱ部分:PECVDSiN的性质及其对GaAs器件性能的影响罗海云(电子部第13研究所,石家庄,050051)PECVDSiNandItsApplicationinGaAsMESFETPartⅡ:Pr...  相似文献   

9.
《电信科学》2001,17(1)
全创通讯的EasyAccessTMDSL接入系统由安装在局端或光纤远端模块(ONU)的AccessExpressTM1000DSLAM和安装于用户端的AccessLinkerTM系列DSLCPE组成,在一条电话双绞线上,除了能为用户提供普通电话业务外,还能为用户提供高容量的交互式多媒体应用,如高速Internet访问、远程局域网访问、视频点播、视频流应用等等。EasyAccessDSL接入系统集成了采用DMT调制方式的ADSL传输系统。DMTADSL传输系统由集成在AccessExpressTM10…  相似文献   

10.
《电信科学》2001,17(3):68-68
可编程逻辑器件(PLD)供应商Altera公司日前推出了业界首枚可编程ASSP ,即新型MercuryTM 系列器件 ,并开始供货。Mercury器件将高速收发器ASSP功能与高性能PLD内核集成在一起 ,可支持最基本和高带宽、高速数据传输速率的应用。Mercury器件内置的时钟数据恢复(CDR)收发器消除了源同步(sourcesynchronous)系统所面临的障碍 ,因此 ,信号传输速率高达1.25Gbit/s,总CDR带宽高达45Gbit/s。这种先进的CDR能力 ,再配合高性能内核和分布式倍增器(Di…  相似文献   

11.
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.  相似文献   

12.
电磁兼容测试结果与检测实验室可靠性程度直接相关,检测实验室自身质量是保证电磁兼容测试结果准确性先决条件,检测实验室测试系统相符性则成为电磁兼容系统性能评估中需要考虑的关键内容和重要指标。因此,检测实验室测试系统相符性比对是实现电磁兼容系统评估研究的基础工作之一。本文首先针对电磁兼容检测实验室测试系统相符性比对的特点,结合自己几年来的测试实践论述了电磁兼容检测实验室测试系统相符性对比方案,然后提出了具体的案例同时进行了详细的分析,最后总结出了影响电磁兼容检测实验室测试系统相符性因素,整个案例和分析过程及结果可作为电磁兼容检测实验室测试系统相符性比对的手段和依据,具有重要的现实指导意义。  相似文献   

13.
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.  相似文献   

14.
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。  相似文献   

15.
量化秩非参数CFAR检测器在杂波边缘中的性能分析   总被引:1,自引:0,他引:1       下载免费PDF全文
孟祥伟 《电子学报》2020,48(2):384-389
人们常用均匀背景、多目标和杂波边缘3种典型背景来衡量雷达目标检测器的性能,但在现有文献中缺乏量化秩(Rank Quantization,RQ)非参数检测器在杂波边缘中虚警概率的理论模型,缺乏RQ非参数检测器与经典的参量型检测器在杂波边缘中虚警控制能力的比较.本文给出了RQ检测器在杂波边缘中虚警概率的解析表达式,并比较了它与非相干积累CA (Cell Averaging),GO (Greatest Of),OS (Ordered Statistic)恒虚警方法在杂波边缘中的虚警控制能力.可以看出,采用高秩量化门限的RQ检测器的虚警控制能力要优于低秩量化门限的情况,在瑞利分布杂波边缘情况下,RQ检测器的虚警控制能力与非相干积累OS方法接近.但是当强杂波变为长拖尾分布的非高斯杂波时,非相干积累CA,GO和OS参量型检测方法的虚警概率产生了3个数量级以上的上升,且不能降回到原始设定的虚警概率.而RQ检测器显示出了非参量检测器的优势,即当杂波背景的分布类型发生变化后,它仍然可以保持虚警概率的恒定.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
五自由度混联机器人因为兼有串联机器人和并联机器人的优点而成为重要的研究方向。在对五自由度并串联雕刻机控制的过程中,求解其输入与末端位置之间的速度及加速度的传递是研究的重点和难点。文中先通过机构拓扑理论对雕刻机的自由度进行分析,再运用矢量法对雕刻机末端运动学进行正向分析,然后采用求导法对雕刻机滑块运动学进行逆向分析,最终通过MATLAB和ADAMS仿真分析验证了雕刻机速度运动学分析的合理性以及算法的有效性。该结果为五自由度混联机器人的实际控制编程提供了参考。  相似文献   

20.
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.  相似文献   

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