E-UTRAN自组织网络(SON)关键技术

首先介绍了SON的主要功能和架构,并重点研究了SON的自动PCI配置、自动邻区关系优化、随机接入优化、移动负载均衡优化、移动性鲁棒性优化、覆盖和容量优化等关键技术,给出了相应的部署策略。     

SON技术是降低网络成本和提高网络效率的利器

介绍了SON技术的目的和主要特征,指出了自规划、自配置、自优化和自恢复的主要功能以及在标准上的主要进展,最后提出了SON技术实施所面临的5个挑战和主要对策建议。     

自组织网络中的自优化技术与方法

文章介绍了移动通信网络的自组织网络(SON)技术;该技术使得网络设备可以自主部署、优化以及操作,从而能够降低网络运营开销、同时提升用户感知。文章重点讨论自优化方案,包括移动负载均衡方案、移动鲁棒性优化方案、随机接入信道(RACH)优化方案、节能优化方案。文章指出未来SON研究将会在新场景下的方案更新、无线接入技术间(Inter-RAT)场景考虑、节能方案的更新等领域进行深化。     

LTE自组织网络技术分析

异构网的引入及多种制式的网络共存使LTE网络运营维护的复杂程度大为增加,为提升网络建设与维护效率,降低网络运营成本,3GPP从R8、R9开始提出了LTE自组织网络(SON)技术.本文介绍了网络自配置、自优化、自愈等LTE SON技术及标准的最新进展,对业界提出的主要功能及其解决方案进行了综合评述.最后结合运营需求,分析了SON技术向端到端、多功能联合发展的趋势.     

LTE自组织网络技术及其应用

异构网(Het Net)的引入及多制式网络的共存,使4G LTE网络运维复杂程度大为增加。2007年3GPP在进行LTE标准制订时,引入了LTE自组织网络(SON)机制,旨在移动网络建设和优化时能自动完成网络设备的参数配置,提升网络建设与维护效率,降低网络运营成本。经过多年的演进发展,SON功能已日渐丰富和完善。介绍了SON技术及其体系架构,举例说明了SON技术在我国的应用情况及效果,提出了SON技术发展面临的挑战。     

LTE自组织网络的覆盖和容量自优化

SON作为LTE的一部分,目的是简化网络管理,实现自配置,自优化和自愈。基于SON背景下,介绍SON用例、分析功能架构,并描述出了流程模型,阐述SON覆盖和容量自优化的实施流程,以及其注意事项,为后续研究提供参考意见。     

自组织网络技术在LTE中的应用

自组织网络技术在LTE的标准化阶段由移动运营商引入,其主要思路是实现无线网络的一些自主功能,减少人工参与。随着LTE网络的逐渐商用,SON将会在LTE建网过程中发挥重要作用。从运营商的角度来看,SON可以帮助运营商降低建设和运营维护成本;从技术角度来看,网络参数的数量越来越多,不同的网络之间需要的互操作,以及快速配置管理增多的基站,这些都促成了SON的发展。本文主要介绍了自组织网络的几个主要功能,即自配置、自优化和自治愈以及他们在网络中的实现方式。     

5G网络自组织优化技术研究

传统的网络自组织优化（SON,Self-Organization Optimization）以网络质量为驱动通过快速优化网络质量以使能网络。随着网络技术的多元化快速发展,传统的网络自组织优化已不能完全适用于未来网络。本文针对5G通信系统自组织技术展开研讨,介绍了传统SON技术发展及理论基础,同时探讨了几个典型5G-SON自优化用例。     

TD-LTE自组织网络SON技术分析和建议

自组织网络SON是TD-LTE的重要技术之一,具有良好发展前景。文章详细描述和深入分析了目前应用于TD-LTE系统中的SON技术,并提出了相关建议。     

IMT—Advanced系统中的自组织网络技术

自组织网络（SON）技术旨在实现网络的自配置、自优化和自治愈，从而帮助运营商降低建设和运营维护成本（OPEX）。文章基于IMT—Advanced系统中自组织网络技术的架构和主要功能，阐述参数自配置、自动邻区关联、容量和覆盖最优化以及移动健壮性优化等自组织网络关键技术的特征和研究方向。     

蜂窝网络自组织研究及展望

自组织网络技术是提高蜂窝网络运行效率、降低运营成本的重要工具,已作为基本功能在4G标准化初始版本获得引入并得到不断发展。在复杂度更高的5G网络中实现网络自动化管理的需求将进一步增强。回顾了蜂窝网络自组织技术的基本概念、分类和主要用例,分析了主要研究方法;总结了学术界、标准化组织及研究机构的研究进展,重点介绍了基于机器学习的最新研究成果;调查了工程应用现状,分析了自组织网络面临的主要挑战,同时指出了新的研究方向。     

基于SON的MOSFET器件及其工艺方法研究

超薄体SOI器件能够有效抑制短沟道效应,业界认为在纳米器件时代它有可能取代传统体硅器件。但SOI器件的全局化埋氧层特性会使其产生自加热效应,严重时会导致器件开态电流下降、漏电流增加,从而导致器件可靠性降低。具有局部空洞层或介质层的SON器件及其制备方法已成为纳米器件时代的一个研究热点。阐述了SON器件的基本概念,比较了SON器件和传统体硅器件的电学特性。对SON器件的工艺制备方法进行了全面描述,包括早期的SON器件制备方法、基于MSTS的SON制备方法、气体注入SON制备方法,以及完全自对准SON器件制备方法。详细描述了准自对准气体注入SON器件和完全自对准SON器件制备方法的工艺流程。     

Analytical I–V model of SOI and SON MOSFETs: a comparative analysis

A generalised three-interface compact capacitive threshold voltage model for horizontal silicon-on-insulator/silicon-on-nothing (SOI/SON) MOSFET has been developed. The model includes different threshold voltage-modifying short-channel phenomena like fringing field, junction-induced 2D-effects, etc. Based on the threshold voltage model, an analytical current voltage model is formulated from the basic charge control analysis of MOSFET. In order to provide a better explanation to various observations and applicable to short-channel SOI and SON structures, the present current voltage model includes the effect of carrier velocity saturation and channel length modulation. Identical structures for both the devices, SOI and SON, are considered but for SON MOSFET, the buried oxide layer is replaced by air. The performance of the two devices are studied and compared in terms of threshold voltage roll-off, subthreshold slope, drain current and drain conductance. The SON MOSFET technology is found to offer devices with further scalability and enhanced performance in terms of threshold voltage roll-off, sub-threshold slope and greater current derivability, thereby providing scope for further miniaturisation of devices and much better performance improvement.     

LTE中自组织网络技术的标准化进展

随着LTE标准的演进,自组织网络（SON）技术也不断发展。由运营商发起的自组织网络不同于传统的无线网络规划、优化方式。SON技术可以减少运营成本,提高操作效率及网络性能和稳定性。介绍了SON的标准化发展情况,重点分析了SON中的几个关键技术。随着SON标准和技术的不断完善,可以预见自组织网络将大大降低未来无线网络的运营成本。     

Service overlay networks: SLAs, QoS, and bandwidth provisioning

We advocate the notion of service overlay network (SON) as an effective means to address some of the issues, in particular, end-to-end quality of service (QoS), plaguing the current Internet, and to facilitate the creation and deployment of value-added Internet services such as VoIP, Video-on-Demand, and other emerging QoS-sensitive services. The SON purchases bandwidth with certain QoS guarantees from the individual network domains via bilateral service level agreement (SLA) to build a logical end-to-end service delivery infrastructure on top of the existing data transport networks. Via a service contract, users directly pay the SON for using the value-added services provided by the SON. In this paper, we study the bandwidth provisioning problem for a SON which buys bandwidth from the underlying network domains to provide end-to-end value-added QoS sensitive services such as VoIP and Video-on-Demand. A key problem in the SON deployment is the problem of bandwidth provisioning, which is critical to cost recovery in deploying and operating the value-added services over the SON. The paper is devoted to the study of this problem. We formulate the bandwidth provisioning problem mathematically, taking various factors such as SLA, service QoS, traffic demand distributions, and bandwidth costs. Analytical models and approximate solutions are developed for both static and dynamic bandwidth provisioning. Numerical studies are also performed to illustrate the properties of the proposed solutions and demonstrate the effect of traffic demand distributions and bandwidth costs on SON bandwidth provisioning.     

A two-dimensional analytical-model-based comparative threshold performance analysis of SOI-SON MOSFETs

A generalized threshold voltage model based on two-dimensional Poisson analysis has been developed for SOI/SON MOSFETs. Different short channel field effects, such as fringing fields, junction-induced lateral fields and substrate fields, are carefully investigated, and the related drain-induced barrier-lowering effects are incorporated in the analytical threshold voltage model. Through analytical model-based simulation, the threshold voltage roll-off and subthreshold slope for both structures are compared for different operational and structural parameter variations. Results of analytical simulation are compared with the results of the ATLAS 2D physics-based simulator for verification of the analytical model. The performance of an SON MOSFET is found to be significantly different from a conventional SOI MOSFET. The short channel effects are found to be reduced in an SON, thereby resulting in a lower threshold voltage roll-off and a smaller subthreshold slope. This type of analysis is quite useful to figure out the performance improvement of SON over SOI structures for next generation short channel MOS devices.     

IMT-Advanced系统自组织网络方案研究

主要研究具有自主管理功能的自组网网络架构、典型应用场景等关键内容。其中,具有自主管理功能的SON网络架构主要考虑自主管理体系架构的选取以及SON和网络管理之间的接口设计;典型应用场景是对最能突出体现IMT-Advanced特征、SON作用的应用场景的概括和提炼。     

Effect of annealing on creation of second-order nonlinearity in twin-hole optical fibre of pure silica

The effect of thermal pre-annealing on the creation of second-order nonlinearity in a pure twin-hole optical fibre thermally poled at 3.5 kV and 280degC for 30 min has been investigated. In unannealed as-drawn fibres, a SON of ~0.18 pm/V was induced at the core-cladding interface. The induced SON showed little polarisation dependence. In fibres pre-annealed at 400degC for 3 h, the induced SON was smaller, decreasing to ~0.09 pm/V in magnitude. In fibres pre-annealed at 800degC for 3 h, no detectable SON was found at the core-cladding interface. Electron-migration along connected existing defects at the core-cladding interface was postulated to be responsible for the frozen-in space-charge field that generated the effective SON observed. Thermal annealing is proposed to have caused defect-annihilation, which resulted in a smaller SON.     

Reliability and Mobility Load Balancing in Next Generation Self-organized Networks: Using Stochastic Learning Automata

Self-organizing networking (SON) is an automation technology designed to make the planning, configuration, management, optimization and healing of mobile radio access networks simpler and faster. Most current self-organization networking functions apply rule-based recommended systems to control network resources which seem too complicated and time-consuming to design in practical conditions. This research proposes a cognitive cellular network empowered by an efficient self-organization networking approach which enables SON functions to separately learn and find the best configuration setting. An effective learning approach is proposed for the functions of the cognitive cellular network, which exhibits how the framework is mapped to SON functions. One of the main functions applied in this framework is mobility load balancing. In this paper, a novel Stochastic Learning Automata has been suggested as the load balancing function in which approximately the same quality level is provided for each subscriber. This framework can also be effectively extended to cloud-based systems, where adaptive approaches are needed due to unpredictability of total accessible resources, considering cooperative nature of cloud environments. The results demonstrate that the function of mobility robustness optimization not only learns to optimize HO performance, but also it learns how to distribute excess load throughout the network. The experimental results demonstrate that the proposed scheme minimizes the number of unsatisfied subscribers (N_us) by moving some of the edge users served by overloaded cells towards one or more adjacent target cells. This solution can also guarantee a more balanced network using cell load sharing approach in addition to increase cell throughput outperform the current schemes.