CSFB无线优化中面临的问题与解决方案

TD-LTE系统是纯IP网络,只提供PS业务,目前TD-LTE系统话音解决方案有单卡双待和话音回落两种,话音回落方案对终端电池的续航能力有较大提升。本文重点介绍了TD-LTE系统话音回落方式、附着流程和主被叫流程,对实际工作中CSFB遇到的典型问题如未开启CSFB功能、回落到2G失败、挂机后不能正常返回4G网络等问题进行细致的信令分析,并给出了优化解决建议。     

TD-LTE网络提升CSFB寻呼成功率的优化分析

介绍TD-LTE系统语音回落方案的指标及关键流程,分析了影响寻呼成功率的原因,并针对给出参数优化、功率优化的解决建议。     

MTRF技术在CSFB话音解决方案中的应用

CSFB是一种TD-LTE话音解决方案,其基本思想是TD-LTE用户通过从TD-LTE网络回落到GSM/TDSCDMA电路域以进行话音业务接续。本文首先介绍了CSFB话音解决方案的关键技术,重点分析了用户被叫流程时回落的重点和难点。其次介绍了MTRF关键技术及其应用场景。最后提出通过MTRF技术可解决CSFB方案的被叫回落异常问题,并分析部署MTRF技术对GSM/TD-SCDMA/TD-LTE融合网络影响。     

CSFB无线优化中面临的问题与解决方案

摘要：TD-LTE系统是纯IP网络,只提供PS业务,目前TD-LTE系统语音解决方案有单卡双待和语音回落两种,语音回落方案对终端电池的续航能力有较大提升。本文中重点介绍TD-LTE系统语音回落方式、附着流程、与主被叫流程,对实际工作中CSFB遇到的典型问题如未开启CSFB功能、回落到2G失败、挂机后不能正常返回4G网络等问题进行细致的信令分析,并给出了优化解决建议。     

TD-LTE系统TA及TAlist规划原则

本文首先介绍了TD-LTE系统位置区的管理机制,其次从TD-LTE系统能力以及目前TD-LTE设备性能等角度,分析了TD-LTE网络的寻呼机制和寻呼容量,最后通过预测LTE小区的用户数目以及单用户寻呼模型,给出了TA/TA list的规划原则和建议。     

基于TD-LTE集群系统的群组寻呼处理策略

在基于TD-LTE宽带多媒体集群系统的基础上,介绍了TD-LTE集群系统中的群组寻呼,提出了一种基于TD-LTE集群系统的群组寻呼的处理策略,该策略有效实现了TD-LTE集群系统中群组寻呼。     

TD-LTE网络CSFB话音方案部署研究

CSFB话音方案作为一种重要的过渡话音解决方案能够满足TD-LTE网络初期部分终端用户话音业务需求,同时解决国际漫游来访。基于试验网测试数据,本文分析了CSFB话音方案回落和返回过程中的关键技术,为CSFB话音方案部署提供建议及参考。     

TD—LTE话音解决方案分析

本文首先介绍了3种主要的TD-LTE话音解决方案,并从标准化情况、端到端产业链成熟情况、对网络的改造要求、对终端的要求、业务体验以及国际漫游环境等多个角度,对话音解决方案进行了对比分析,特别对电路域业务回落技术（CSFallBack,CSFB）的具体实现方式进行了对比分析,并给出TTD-LTE话音解决方案的应用建议。     

TD-LTE寻呼过程及寻呼流量分析

文章首先介绍了TD-LTE的寻呼过程;然后分析影响TD-LTE寻呼流量的参数,并给出了计算寻呼流量的公式;最后介绍TD-LTE跟踪区的计算方法,并指出了TD-LTE跟踪区列表所能容纳的小区建议值。     

TD-LTE高速铁路场景专网分析

本文首先对TD-LTE专网优化难点进行了介绍,随之基于海量数据对关键参数与下载速率的相关性进行了分析。同时,基于TD-LTE专网优化难点从站址选择、组网规划和邻区设置等方面提出了优化建议。并对高速铁路的CSFB优化邻区设置进行了总结,提出了提升回落精准性的策略。最后,对未来的高铁覆盖提出了两种覆盖模型展望,其中明确指出了基于载波聚合技术的车载分布系统将更能为终端用户提供较好的业务体验。     

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.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

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.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

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.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method 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.     

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.