软交换信令网关中M3UA协议的实现技术(上)

本文介绍了软交换、信令网关和M3UA协议，提出了实现M3UA协议的软件模型。该模型采用模块化设计的思想和多进程机制，实现M3UA协议在信令网关中的功能。最后文中示范性地介绍了SCTP关联管理模块和ASP维护模块的实现要点。     

SigTran在3G组网中的应用

信令传输(SigTran)协议簇是由IETF的SigTran工作组制定的一系列协议,包括流控制传输协议(SCTP)和用户适配层(UAL)协议。SCTP协议弥补了传输控制(TCP)协议的很多漏洞,主要用于在IP网络上可靠传输信令消息;适配层协议包括M2UA、M3UA、SUA等UA协议,UA层的作用就是将电路域的消息进行适配封装,使其顺利在IP域传输,完成电路域与IP域的兼容与互通。文章主要讨论了SCTP协议的功能以及SCTP协议的数据传输方式,UA层协议的代表M3UA的功能及应用,并进一步阐述了SigTran在3G组网中的应用。     

软交换信令网关中M3UA协议的实现

文章首先对软交换、信令网关和M3UA协议进行了介绍,然后讨论了M3UA协议的具体实现,采用模块化设计的思想,通过模块调用来完成M3UA在信令网关中的功能,最后简单介绍了M3UA的接口原语及网络安全的问题．     

软交换下VoIP话务量与IP带宽间关系的分析及应用

随着软交换、网络IP化等技术的演进，交换机实现了控制和承载的分离，传统的信令、语音业务都通过IP网络承载的信令流和媒体流进行传送。在分析信令流的IP承载带宽时，需要考虑M3UA Sigtran、IP等各种协议栈的开销以及Mc、Nc等接口中各种信令流程下的消息流量和消息包的大小。相对于媒体流而言，信令流在整个IP带宽中占比很小，带宽规划时一般按一定比例进行估算，因此，这里对信令流的带宽关系不作进一步研究。     

采用软交换技术实现MSC冗灾备份

本文通过对软交换技术架构、组网方式、话务信令路由等方面的分析,探讨如何采用软交换技术对传统移动交换端局进行冗灾备份.     

NGN中路由配置方案的比较

本文首先介绍NGN的基本概念和网络构架,接着介绍了软交换的概念和体系结构,然后针对目前NON建设的现状,提出了NGN中的3种路由解决方案：平面软交换路由体系、层次化的软交换路由体系和服务器定位方案,并对这3种方案的优劣进行比较分析,平面软交换路由结构简单,建设成本低,因此在网络运营的初期,可以采用该方式,当网络规模扩大到一定程度,就需要采用分级的路由结构。层次化软交换路由体系中,软交换机根据呼叫信令进行逐跳路由,因此呼叫接续时延较大,但这一方案比较成熟,LS路由则是呼叫信令直接在起始和目的软交换机之间传递并处理,但相对前者成熟度不高。本文的一个重点是介绍TRIP的概念,因为它将是NGN的标准路由协议。     

信令IP化承载技术问题分析

文章围绕信令IP化承载试点,分析了信令IP化组网结构,重点研究了信令IP化承载的技术问题,包括站点接入方案、IP地址需求、M3UA/M2PA/SCTP偶联配置和时间同步,对推动现网信令IP化承载有着积极意义.     

SIGTRAN在3G核心网中的应用

SIGTRAN是IETF提出的在IP网上传输七号信令的协议簇，SCTP和M3UA是该协议簇中的两个协议。简要介绍了SCTP和M3UA的特点，就其在第三代移动通信核心网的应用中存在的若干问题进行了分析和讨论，并对如何解决这些问题提出了一些看法。     

七号信令网关及其新发展

七号信令网关是软交换体系结构中的重要功能实体。它位于软交换体系的接入层，实现七号信令网与IP网的互通。随着下一代网络的发展，七号信令网关在组网应用、信令协议、实现方法和接口与功能等方面都有新的发展。     

SIP在视讯会议中的应用和发展——当今最热门的通信协议

SIP(Session Initiation Protocol，会话发起协议)是由IETF(互联网工程任务组)提出的IP电话信令协议。它的主要目的是解决IP网中的信令控制，以及同Soft Switch(软交换)的通信，从而构成下一代增值业务平台，为电信、银行、金融等行业提供更好的增值业务。     

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.     

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.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks