Cognition Flow in Cognitive Radio Networks

This paper introduces the research progress on the cognition flow in the National Basic Research Program of China （973 Program） under Grant No. 2009CB320400 ＂Research on Basic Theories and Key Technologies of Cognitive Radio Networks＂. We present the motivation behind the proposal of the concept of cognition flow, provide the definition, discuss the features, behaviours, representations, math- ematical models, and the functions of cognition flow in Cognitive Radio Networks （CRNs）. We also analyse how the cognition flow promotes the convergence of heterogeneous networks. Our group also constructed the test platform to verify the usefulness of cognition flow. The results that were simulated by computers and tested on the platform both confirm that cognition flow can realise efficient interaction of cognitive information among heterogeneous networks in CRNs, which contributes to the seamless convergence of heterogeneous networks, and significantly improves the spectrum efficiency and users＇ Quality of Experience （QoE）.     

QoE领域新进展及其在最小化路测（MDT）方面的新应用

用户体验质量（QoE）是重要的网络评价指标。文章首先讨论面向用户感受的网络质量评价的一些技术挑战：其次介绍QoE领域的数项最新进展,包括3G网络典型业务视频及多媒体QoE技术的科研进展及标准化进展,QoE指标体系研究的进展等;最后提出一种创新的面向QoE的MDT模式,以期推动QoE及网络建设,优化技术的发展。     

一种基于QoS的QoE到SLA映射方法

该文提出一种算法IQoE2QoS(Improved QoE to QoS),采用模糊理论的方法计算QoE到QoS的映射。该算法有3重目标：从大量的经验数据中通过计算互信息量方式总结被统计指标之间的关联程度。在大量经验数据的基础上通过多指标模糊判定理论将用户感知映射到应用层用户QoS参数。考虑了用户的QoE和QoS的双向映射,并且阐述了得到的QoE如何自然映射到SLA(Service Level Agreement)。通过仿真表明,IQoE2QoS算法对用户体验的分类准确度是线性回归算法的2到3倍。     

应用于数字和模拟光通信的高速电吸收光调制器

An electro-absorption （EA） modulator is one of key components for optical fiber communications due to the high speed, small size, low voltage and integration ability with other semiconductor devices. A 40 Gb/s InGaAsP/InP multiple-quantum-well （MQW） EA modulator monolithically integrated with a semiconductor optical amplifier （SOA） was fabricated for digital communications. The modulator capacitance was reduced to obtain 40 GHz bandwidth, and the SOA section helped reduce the insertion loss from 18 dB to 3 dB. InGaAlAs/InP MQW EA modulators have also been fabricated and characterized for analog optical fiber communications. A low driving voltage of 2.7 V and high spurious free dynamic range of 107 dB·Hz^2/3 were estimated by static and dynamic measurements.     

面向差异化QoE基于匹配理论的任务卸载与资源分配方案

随着6G通信网络和移动边缘计算（mobile edge computing,MEC）技术的迅速发展,配备边缘服务器的基站部署密度持续提高,计算任务呈现出日益多样化的趋势。为应对差异化用户体验质量（quality of experience,QoE）以及资源分配不均衡对系统性能的影响,提出了一种高效的匹配卸载方案,综合考虑了卸载决策以及计算资源分配,构建了一个以最大化系统收益为目标的混合整数非线性规划问题。通过分解原问题,基于双边匹配理论设计了一种迭代优化算法加以求解。仿真实验基于澳大利亚墨尔本中央商务区（central business district,CBD）的公共数据集进行验证,结果表明,与现有方案相比,所提方案在提升系统收益方面表现出显著的优势。     

基于解码缓冲信息的IPTV QoE策略

提供一种可在IPTV用户的终端接收设备上评测QoE(Quality of Experience)的方法。该方法通过实时监测设备上的解码缓存的状态以及缓存中的媒体丢失率作为参数,并基于统计和实验数据建立这些参数和QoE的函数关系,最终给出它们之间的推算公式来量化当前流媒体视频的QoE等级(MOS值)。考虑到终端设备(如IPTV机顶盒)的处理能力在应用中还会对相应方法做一些优化。     

基于QoE的路测软件数据存储与分析模块设计与实现

传统的基于KPI评估体系的路测软件不能满足无线网络优化中用户感知（QoE）的要求,本文以QoE为导向,采用内存-磁盘映射存储机制设计出了一种适合路测软件的数据存储结构,提出了一种后台数据分析模块的设计方案,使用分析管理器为用户提供定制自定义分析项目的接口,使用表达式编辑器为用户提供定制自定义参数、事件和指标的接口。实际测试结果表明,数据库系统的设计很好的满足路测软件对数据存取的要求,后台分析模块的设计使得后台数据分析更加灵活高效,符合QoE评估体系的要求。     

Quantitative and qualitative research on service quality evaluation system in NGN

With the development of next generation network (NGN), reasonable service quality evaluation is essential in network management. Based on NGN service characteristics, this article presents a comprehensive service quality evaluation system from two perspectives: quantitative and qualitative. From the quantitative point of view, this article brings forward the normalized service level achievement function (NSLA function) at technical layer. Also, with mean opinion score (MOS) mode, it proposes customer satisfaction assessment methods at customer perception layer. From the qualitative perspective, a hierarchical model is established, which forms mapping relations from the upper customer perception to the lower service quality parameters, and then the influence of different service parameters on customer satisfaction degree can be denoted by the fuzzy analysis hierarchy process (FAHP) algorithm. Quantitative and qualitative evaluations together form a comprehensive solution which is universal, customer-oriented and flexible. Demonstrated by the representative voice service, the proposed system is proved reliable and applicable to service evaluation in NGN.     

IPTV服务质量关键技术研究

IPTV服务质量直接影响用户的体验,是IPTV得以运营的关键技术之一。目前国内外致力于提高服务质量的技术研究,尚未形成标准。本文结合QoS和QoE分析IPTV服务质量的关键技术,从区分服务模型、MDI和基于IPv6的频道切换技术的角度提出改进IPTV服务质量的方案。