3G传输网构建浅析

从传输网的角度而言，在三个3G主流标准WCDMA、CDMA2000和TD-SCDMA中，WCDMA的业务侧接口种类最多。另外，在全球已颁发的3G执照中．有接近甚至超过80％是基于WCDMA的执照．这样．对于WCDMA的技术及其组网研究最有典型意义．因此．本文主要分析WCDMA传输网络构建的解决方案．而相关的分析或结论也适用于CDMA2000和TD-SCDMA的传输网络。     

WCDMA系统及其关键技术探讨

本文讨论了CDMA的发展历程，分析了CDMA移动通信环境中面临的问题，分析了WCDMA系统中的关键技术，以及WCDMA技术的主要特点，最后在WCDMA的基础上，提出了增强网络性能的新方法。     

WCDMA系统及其关键技术探讨

本文讨论了CDMA的发展历程以及CDMA移动通信环境中面临的问题，分析了WCDMA系统中的关键技术，WCDMA技术的主要特点，最后在WCDMA的基础上，提出了增强网络性能的新方法。     

车载双模无线视频监控系统的设计与实现

设计并实现了一种基于WCDMA和CDMA2000 EVDO无线3G网络的车载式双模无线视频监控系统。介绍了车载式视频监控终端嵌入式设备的整体硬件结构,以及相应功能模块定义和说明。从系统总体结构、主要流程图和关键技术等方面详细描述了监控中心的软件实现。测试结果表明,该车载式监控系统充分利用WCDMA和CDMA2000 EVDO双模网络进行数据传输,相比于传统单模视频传输系统,有效提高了视频传输质量。     

车载式无线双模音视频传输监控系统设计与实现

基于CDMA2000和WCDMA的无线网络,设计并实现了车载式音视频监控系统,包括运行于后台的监控中心子系统和运行于终端的调用子系统.重点阐述了该监控系统中监控终端以及监控中心的软件设计和关键技术.系统在工程环境下进行了调用测试,测试结果表明,基于该设计的车载终端充分利用了CDMA2000和WCDMA网络的传输带宽,相对于单模的音视频传输,在传输效果上有较大的提高.     

手持式无线双模音视频传输软件设计与实现

设计与实现了一种基于WCDMA和CDMA20001X手持式双模音视频传输终端.重点针对终端系统软件体系架构、软件功能模块、双模传输调度关键技术等方面进行设计与实现.搭建双模音视频传输监控测试平台,测试结果表明相比于单模传输系统,利用WCDMA和CDMA20001X两个无线网络进行数据传输,有效提高了系统性能.     

WCDMA系统及其关键技术探讨

本文讨论了CDMA的发展历程,分析了CDMA移动通信环境中面临的问题,分析了WCDMA系统中的关键技术,以及WCDMA技术的主要特点,最后在WCDMA的基础上,提出了增强网络性能的新方法。     

WCDMA系统及其关键技术探讨

本文讨论了CDMA的发展历程,分析了CDMA移动通信环境中面临的问题,分析了WCDMA系统中的关键技术,以及WCDMA技术的主要特点,最后在WCDMA的基础上,提出了增强网络性能的新方法.     

CDMA2000 1x EV—DON络建网探讨

文章介绍了CDMA2000 1x EV—D0的技术特点，分析了CDMA2000与GSM、WCDMA网络规划的区别，最后对CDMA2000的网络规划进行了探讨，并提出建议。     

第三代无线接入网传输技术和解决方案浅析

对应于3G的网络结构,用于承载3G业务的传输网络分为核心传输网络和接入传输网络。文章重点分析适用于3G无线接入的传输网络技术,并给出适当的解决方案。同时,由于WCDMA、CDMA2000和TD-SCDMA在RAN部分网络结构非常相似,在RAN部分的组网也基本没有区别,所以这里将以WCDMA为例做进一步的讨论。     

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.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

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.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

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.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.