LTE寻呼优化方案研究

分析了LTE网络中的寻呼优化需求,针对固定位置或低移动性终端,提出2种解决方案,分别是基于网络侧的寻呼优化方案和基于终端的寻呼优化方案,并分析了对现有网元功能的影响,从而在保证一定的寻呼成功率的基础上,通过减小寻呼区域的方式来降低寻呼的信令负荷。     

缓解EV-DO智能终端信令风暴的方法

随着智能手机的普及,越来越多的手机用户习惯于直接点击手机桌面图标的方式来使用网络服务,导致移动网络信令负荷的迅猛增长,最终产生信令风暴。文章从EV-DO网络在无线侧信令风暴产生机制分析,结合EV-DO的寻呼策略原理提出解决方案,并以华为设备为例论证解决方案的可行性和有效性。     

移动IP网络中基于遗传算法的多步寻呼策略及性能分析

在移动IP网络中,层次移动IP协议可降低移动IP位置管理的信令消耗。该文研究支持寻呼的HMIPv6,提出了时延限制下的多步寻呼策略以及基于遗传算法的多步寻呼方案——根据移动节点的位置概率分布,采用遗传算法对寻呼区域内的所有子网进行分组,每步寻呼一个组,使平均寻呼信令开销达到或接近最优。此外,对HMIPv6、单步寻呼的HMIPv6以及基于遗传算法的多步HMIPv6寻呼方案的信令开销进行了比较分析,得出寻呼节省信令开销的必要条件。最后,给出一组数值结果以说明所提出的寻呼策略的有效性。     

中国移动应对信令风暴的风险体系

对运营商而言,巨量的在线业务必然会对收入带来益处,但是频繁的联网、待机的状态转换也正是产生信令风暴的根源。四网协同的时代,流量管控成为中国移动网络优化的重中之重。针对信令风暴,各大通信设备、终端厂商纷纷表示,要进一步升级、改进相关软件协议,以降低信令需求,更多的方法是增加设备处理能力,提供大容量的信令处理单元。     

一种应用位置预测的动态寻呼框架

移动通信系统里评估系统的一项重要指标是用户在移动过程产生的信令消耗。在现行4G网络中,当核心网向目标终端发送寻呼时,在跟踪区域列表里的所有小区都要发送寻呼信令,造成了不必要的信令浪费。为减少寻呼信令的消耗,提出了一种移动性管理的框架,此框架可以分为预测部分和回落部分,其中预测部分提供了移动性管理与预测算法有机结合的方案,回落部分则使用马尔科夫链对寻呼过程进行分析,在预测失败时采取动态寻呼的方式。对该框架进行建模和仿真可以看出,所用的寻呼方案能有效减少移动终端的非接入层处于空闲态时进行移动性管理中寻呼信令的开销。     

一种TD-SCDMA用户并发业务故障的分析

针对TD-SCDMA网络因为设备异常而导致PS业务中的用户无法被寻呼,造成来电漏接的问题,通过从无线侧/核心网侧分析与论证,探索问题成因及异常信令跟踪等解决方案,总结经验,重视用户投诉与现场测试,后台实时进行信令跟踪与分析等,给TD-SCDMA系统的维护和优化问题提供了一定的参考。     

LTE网络中的寻呼优化方法研究

现有LTE网络中,寻呼是基于TA list进行的.由于实际网络中为UE分配的TA list覆盖范围有限,TA list的作用得不到充分发挥.通过对LTE网络中的寻呼方法进行优化,可减少整个TA list的寻呼次数,减轻LTE网络的寻呼负荷,从而可以进一步扩大TA list的覆盖范围,这样可减少UE的位置更新次数和网络信令负荷,增加UE待机时间.     

LTE网络RRC重建性能提升三板斧

RRC重建(RRC connection re-establishment)是UE处于RRC_CONNECTED状态,因为一些移动性管理或底层链路故障,导致连接中断,UE发起的空口资源重新建立的过程,以继续空口的RRC连接.重建的意义在于快速恢复空口业务,提高业务的连续性.RRC重建是由终端发起,目前商用网络终端发起重建原因在信令里仅显示为重配置失败、切换失败、Other三种原因,详细是什么原因导致发生重建,在RRC重建请求消息里并没有更多信息.所以需要从多条基站侧信令中分析RRC重建根本原因,但是日常定位重建问题原因的方法需要逐条信令查看,并与多条切换信令相对比,不仅繁琐,且分析准确性低.     

移动互联网中的网络技术

从移动性管理、轻量级IP协议适配、多接口异构网络接入等方面入手,对传统IP网络的发展策略进行了探讨.针对造成移动通信网“信令风暴”的原因,提出了从移动终端、无线接入网、核心网等层面共同解决“信令风暴”的对策.     

智能手机产生的信令风暴解决方案研究

文章分析了WCDMA网络中智能手机信令风暴产生的原因,提出了一种通过增加系统控制参数来主动调控智能手机信令负荷的解决方案,并验证了此方案的可行性.该方案在不影响用户体验和KPI指标的前提下,通过软件功能减少了WCDMA网络智能手机产生的信令负荷,有效抑制了信令风暴的产生,并降低RNC信令处理模块CPU负荷10％左右,提高了主设备的利用率.     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.