Wireless Sensor Network Based Smart Grid Communications: Challenges,Protocol Optimizations,and Validation Platforms

Wireless Personal Communications - Smart grids, the next generation of electric grids, require the deployment of sophisticated monitoring and control systems to enhance their operational...     

认知无线电网络中的频谱感知技术及面临的挑战

频谱感知作为认知无线电的关键技术之一,允许非授权用户伺机访问未使用的授权频带资源,从而大大改善了频谱利用率,并且具有较低的部署成本和较好的兼容性。文章首先介绍了认知无线电的概念和频谱感知提出的背景;然后详细探讨了频谱感知面临的技术挑战和设计权衡,并考虑了安全性问题;最后对可能威胁频谱感知的安全问题进行了说明并给出了结论。     

面向生物视觉的神经编码模型研究：进展与挑战

视觉系统通过神经元将丰富且密集的动态视觉刺激编码成时变的神经响应。探寻视觉刺激与神经响应之间函数关系是理解神经编码机理的一种常见手段。该文首先介绍了视觉系统的神经编码模型,归纳为两类：生物物理编码模型和人工神经网络编码模型。然后介绍了各种模型的参数估计方法。通过对比各种模型的特性,总结了各自的优势、应用场景及所存在问题。最后,对视觉编码研究的现状以及未来面对的挑战进行了展望。     

空地协同视觉实现无人机自主降落研究

在深入分析了无人机视觉降落多种方式的基础上,结合无人机连续视觉图像的三维空间信息,提出了基于空地协同视觉信息的无人机自主降落方法,设计了一种多图形组合、多色彩导引、多方法识别的地面合作目标.从坐标系的转换、合作目标的选取、识别与处理等方面进一步细化论述空地协同视觉完成无人机自主降落的方式,通过灰度变换、HSV色彩变换、HU不变距匹配等方法保障了合作目标的准确识别率.     

无线认知开发平台综述

随着各种各样无线应用的增加,频谱资源日趋紧张。认知无线电基于对无线通信环境的感知、规划、决策和调度,可采用动态频谱接入等方式以有效地提高授权频段的利用率,认知无线电开发平台对其相关技术的研发至关重要。介绍了典型认知节点的结构框架、部分硬件开发平台及其相关软件开发环境,给出了4种国外基于认知无线电的网络化测试平台的构成及特性,展望了可应用无线认知平台的未来研究领域。     

Dynamic Collaborative Cloud Service Platform: Opportunities and Challenges

This letter presents a model for a dynamic collaboration (DC) platform among cloud providers (CPs) that prevents adverse business impacts, cloud vendor lock‐in and violation of service level agreements with consumers, and also offers collaborative cloud services to consumers. We consider two major challenges. The first challenge is to find an appropriate market model in order to enable the DC platform. The second is to select suitable collaborative partners to provide services. We propose a novel combinatorial auction‐based cloud market model that enables a DC platform among CPs. We also propose a new promising multi‐objective optimization model to quantitatively evaluate the partners. Simulation experiments were conducted to verify both of the proposed models.     

无线Ad hoc 网络及其研究难点

无线Ad hoc网络作为没有基础设施的网络，在军事和民用方面具有广阔的应用前景，是目前网络研究中的热点问题。本文对无线Ad hoc网络进行了详细的论述，指出了目前研究中存在的一些难点。     

认知通信网技术研究

认知通信网技术是在认知无线电(Cognitive Radio)和自组织网络技术基础上发展起来的一种新兴的通信网技术。认知通信网能够感知其内部和外部环境的变化,以及用户需求的变化,实时调整通信网各层的通信资源和能力,智能地适应环境和用户多样化需求的变化。给出了认知通信网技术的内涵、研究现状、体系结构及关键技术,对认知通信网的发展提出了设想与建议。     

军事认知通信网络研究

针对军事通信网络的网络抗毁重建、服务质量、异构性互连互通方面的需求分析,提出了构建军事认知通信网络。论述了军事认知通信网络的体系结构,包括网络组成、功能实体、工作流程和网络要素;比较分析了军事认知通信网络与目前网络的突出功能特点;描述了认知环境多域认知技术、认知智能决策和重配置等关键技术。     

Novel Research on Cognitive Pilot Channel in Cognitive Wireless Network

With the irreversible trend of the convergence and cooperation among heterogeneous wireless networks, the need for network information awareness of user equipments (UEs) becomes increasingly imperative in the Cognitive Wireless Network (CWN). As one of the candidate solutions for network information delivery for UEs, the Cognitive Pilot Channel (CPC) concept has been brought forward recently, providing UEs with the necessary network information for network selection by using the public signaling channel. Furthermore, the coverage area of CPC is divided into meshes and terminals could receive corresponding information according to their location in mesh. In this paper, an optimal mesh division scheme in CPC is brought forward, trying to analyze the impacts of different parameters such as the delivery information accuracy, information loss and position accuracy to the mesh division scheme. In order to improve the on-demand CPC delivery efficiency, an optimized multicast CPC scheme is designed and evaluated, which remarkably reduces the time delay of information delivery. Numeric experimental results validate the rationality and effectiveness of the proposed scheme and strategy.     

无线传感器网络关键技术及其研究难点

本文在简要介绍无线传感器网络特点的基础上,给出了无线传感器网络的体系结构,在此体系结构下,系统地阐述了无线传感器网络的研究现状,并指出了尚存在的难点和可能的研究方向.     

认知网络与网络融合

分析了在无线技术快速发展背景下异构网络融合的特点和技术要求,阐释了认知网络概念及其“目标-认知决策-重配置”三层次网络结构模型,描述了作为认知网络基础的上下文感知、跨层设计和重配置三个关键技术,最后讨论认知网络在异构网络融合中的应用前景。     

迎接ASON网络管理的挑战

自动交换光网络（ASON）技术是当前光网络领域研究的热点技术，但是有关ASON管理平面的研究工作和标准化才刚刚起点，从网络管理的角度描述了ASON的特点，分析了对ASON的传送平面和控制平面的管理要求，其中对控制平面的管理要求做了重点讨论，最后提出了现行的ASON网络管理方案，并针对不同的用户角色提出了建议。     

多机被动定位协同平台自适应选取研究

针对多机测角被动定位精度提升问题,提出了一种低速数据链条件下载机运动无约束的协同平台自适应选取方法。在算法实现中,首先推导了一种基于圆概率误差的协同平台自适应选取函数,并给出了两平台自适应选取函数的具体公式,其次给出了协同平台自适应选取设计方法,最后是节点选取的求解方法。仿真结果表明,所提出的算法能够实时地根据敌我位置相对几何关系,动态选取参与目标位置解算的协同平台,大大提高了多机被动定位系统的定位精度。     

Collaborative Network Transformation

The directions that a typical service provider is thinking along today are so varied. This paper will first take a look at some of the thoughts that are shaping a typical service provider’s mindset today. These thoughts stem from new technology options, increased competition, new and different customer behavior, and new business models. Based on today’s observations, combined with the desire to be prepared for the different opportunities and challenges they expect to see in the future, service providers have embarked upon a huge network transformation exercise. This paper will attempt to highlight the complexity such a network transformation exercise would entail. While they remain focused on their strategic initiatives, options for the service provider to partner with others to make the network transformation task a little easier will be explored. Should they choose to go with a network transformation partner, recommendations on how to choose and work with the right partner are provided.

6G愿景及技术挑战专题导读

随着5G商业化的加速,6G逐渐成为全球各国着力部署的方向。早在2018年3月,中国工业和信息化部就宣布着手6G的研发工作。2019年11月,中国科技部会同国家发展改革委员会、工业和信息化部、教育部、自然科学基金委和中国科学院成立国家6G技术研发推进工作组,正式部署中国6G的研究工作。2020年3月4日,国际电信联盟(ITU)在国际移动通信工作组(WP5D)会议上,启动了面向2030年及未来6G的研究工作。这标志6G被正式纳入国际标准组织研究计划。     

Spectrum Challenges and Solutions by Cognitive Radio: An Overview

This paper provides an overview of major problems that are confronting wireless communication with regard to spectrum use in general i.e. by all sectors, government, private, other telecom service providers and military communication. It is commonly believed that there is a crisis of spectrum availability due to tremendous growth in the wireless based systems and the evolution of the radio communication technologies. In fact, there is no shortage of radio spectrum, only a dearth of affordable communications infrastructure. There is potential to make considerably better usage of the radio-spectrum. There are many areas of the radio spectrum which are not fully utilized. Cognitive radios (CR) have been proposed as a way to reuse this underutilized spectrum in an opportunistic manner. A CR is an autonomous unit in a communications environment that senses its environment, tracks changes, and reacts upon its findings and frequently exchanges information with the networks. We show the how the radio frequency is being managed in India and what India is doing to face the challenges to improve the spectrum management. The radio Communication Assembly of ITU is also studying the plan for implementation of CR systems including technical and regulatory issues.

基于社会网络协同过滤的社会化电子商务推荐研究

随着社会网络关系的不断复杂化,商品是否推荐成功,除了基于商品本身的特征外,还受社会网络关系的影响。很多用户更加信任来自朋友的推荐,而非机器通过单因素计算出来的推荐结果。因此,设计了一个融入社会网络关系的电子商务推荐系统。其中,构建了社会网络关系强度、兴趣偏好强度和商品流行性与声望强度3个关键因子,每个一级因子又由若干个二级因子构成。实验结果验证了社会网络关系会对其中成员的网购等网络行为产生影响,构建的基于社会网络的电子商务推荐策略的效果比其他单因素推荐策略好且稳定,具有很好的实际应用效果。     

5G专网核心网部署模式与挑战

5G商用网络快速推进,垂直行业对5G网络有着巨大的需求,针对5G行业市场,运营商正在积极探索5G专网的建网模式和方案.分析了5G专网的需求和应用情况,阐述了5G网络架构特征及专网使能技术,提出了5G专网核心网部署方案,并探讨了5G专网部署面临的问题与挑战.