认知无线电网络层路由问题研究

在认知无线电中,网络层用于确定如何在网络中找到一条从源节点到目标节点的路径,且数据路径应当是适应频谱状况的,即尽可能绕过主用户频繁出现的区域。由于频谱是随机的,因而数据路径也可能是随机的。文章分析认知无线电网络中路由面临的挑战,介绍认知无线电网络中的两种路由方案:静态路由和动态路由,给出静态路由频谱选择阶段的5个指标,研究静态路由下一跳选择阶段的优化问题,最后提出认知无线电网络动态路由的实现方案。     

混合式认知无线电网络路由算法研究

由于认知无线电网络频谱的动态性和差异性,使得传统路由算法不能完全适用.通过分析、总结动态频谱与路由跨层设计研究现状,针对混合式认知无线电网络,以着色图模型为分析模型,为避免交叉节点出现影响网络通信性能,将跳数和链路状态的加权和作为路由选择依据,以最小累积干扰为信道分配指标,提出了一种信道分配和路由选择改进算法(ICARS).仿真结果表明,ICARS算法能获得更好的网络通信质量,为混合式认知无线电网络路由设计提供了一种有效方法.     

一种新颖的认知无线电组播路由协议

由于认知无线电(CR)网络具有频谱动态性、频谱差异性以及频谱多样性等特点,传统的组播路由策略已不再适合于CR网络,CR组播路由面临新的挑战。结合博弈论知识建立了频谱分配模型并得出了最优的纳什均衡解,详细介绍了基于时延约束的CR的组播路由协议并对其进行了分析,最后指出其进一步的研究方向。     

动态频谱分配与频谱共享研究综述

文中针对当前无线频谱政策和无线频谱技术局限所导致的频谱整体利用率低的问题,分析了能有效提高频谱利用率的动态频谱分配和共享技术的研究现状,包括相邻和分片动态频谱分配技术,共存和覆盖式频谱共享技术,感知无线电技术,以及频谱池技术,并讨论了其未来的研究方向,尤其是感知无线电和基于OFDM的频谱池方法.     

认知无线电技术的国内外发展和研究现状

认知无线电是一种智能频谱共享技术.它通过感知频谱环境、智能学习并实时调整其传输参数,实现频谱的再利用,可显著地提高频谱的利用率.在概述了认知无线电基本概念和功能的演进之后,重点介绍了认知无线电技术在国内外的发展和研究现状,包括相关频谱政策和标准化工作进展,以及物理层技术、媒体接入控制协议和网络路由协议等热点问题的研究成果.     

认知无线Mesh网络跨层设计研究

传统网络的分层设计不能满足具有特殊QoS需求的无线宽带业务,无法应对动态频谱接入的无线通信环境。采用联合开放、架构灵活的跨层设计研究无线Mesh网络接入技术日渐成为热点。本文首先介绍了跨层设计的起源、分类,然后分析了认知无线Mesh网络跨层研究的挑战、难点及最新进展,并提出利用跨层设计实现路由及频谱管理的一种构想,最后展望了认知无线Mesh网络跨层研究的新方向。     

基于服务的动态频谱管理技术

在现代战争中,战场频谱管理是夺取制电磁频谱权的重要保障。针对当前战场频谱管理的热点问题,通过介绍动态频谱管理因素、基于服务的动态频谱管理体系架构、动态频谱管理层次分析和动态频谱管理系统模型,对动态频谱管理技术进行研究,并详细分析了系统级动态频谱管理和网系级动态频谱管理。     

物理损伤感知的多芯光纤网络动态路由资源分配方法

针对多芯光纤空分复用弹性光网络中物理损伤导致网络的频谱利用率低与带宽阻塞率高的问题,提出一种物理损伤感知的业务动态路由和资源分配方法.在路由阶段,设计考虑路径跳数、可用资源和路径上链路资源利用率的动态路径资源评判公式,选择负载均衡和资源占用较少的候选路径.在频谱和纤芯分配阶段,设计满足业务串扰和非线性阈值的纤芯和频谱分...     

基于图论的动态频谱分配

在认知无线电系统中,动态频谱分配是决定能否充分高效利用有限频谱的关键.文中建立起网络拓扑模型,分析了基于图论着色模型的动态频谱分配技术的发展过程、研究现状.并讨论了其未来的研究方向,主要是在算法改进上.     

基于认知无线电技术的动态频谱接入

文章介绍了基于认知无线电的动态频谱接入技术,并对其网络架构、关键技术以及目前的研究现状进行了详细分析。在此基础上探讨了动态频谱接入网络中采用跨层协议设计方法的必要性。     

Power-aware routing protocols in ad hoc wireless networks

An ad hoc wireless network has no fixed networking infrastructure. It consists of multiple, possibly mobile, nodes that maintain network connectivity through wireless communications. Such a network has practical applications in areas where it may not be economically practical or physically possible to provide a conventional networking infrastructure. The nodes in an ad hoc wireless network are typically powered by batteries with a limited energy supply. One of the most important and challenging issues in ad hoc wireless networks is how to conserve energy, maximizing the lifetime of its nodes and thus of the network itself. Since routing is an essential function in these networks, developing power-aware routing protocols for ad hoc wireless networks has been an intensive research area in recent years. As a result, many power-aware routing protocols have been proposed from a variety of perspectives. This article surveys the current state of power-aware routing protocols in ad hoc wireless networks.     

无线传感器网络路由协议安全性研究

无线传感器网络的特性使它面临着比传统网络更大的安全挑战。路由协议作为无线传感器网络的关键因素,其安全更为重要。介绍了无线传感器网络路由协议分类及其脆弱性,分析了几种网络路由协议的攻击方法,阐述了网络路由协议的安全策略。     

A Tabu search based routing algorithm for wireless sensor networks

In this paper, a Tabu search based routing algorithm is proposed to efficiently determine an optimal path from a source to a destination in wireless sensor networks (WSNs). There have been several methods proposed for routing algorithms in wireless sensor networks. In this paper, the Tabu search method is exploited for routing in WSNs from a new point of view. In this algorithm (TSRA), a new move and neighborhood search method is designed to integrate energy consumption and hop counts into routing choice. The proposed algorithm is compared with some of the ant colony optimization based routing algorithms, such as traditional ant colony algorithm, ant colony optimization-based location-aware routing for wireless sensor networks, and energy and path aware ant colony algorithm for routing of wireless sensor networks, in term of routing cost, energy consumption and network lifetime. Simulation results, for various random generated networks, demonstrate that the TSRA, obtains more balanced transmission among the node, reduces the energy consumption and cost of the routing, and extends the network lifetime.     

An ant colony optimization based routing algorithm for extending network lifetime in wireless sensor networks

Reducing the energy consumption of network nodes is one of the most important problems for routing in wireless sensor networks because of the battery limitation in each sensor. This paper presents a new ant colony optimization based routing algorithm that uses special parameters in its competency function for reducing energy consumption of network nodes. In this new proposed algorithm called life time aware routing algorithm for wireless sensor networks (LTAWSN), a new pheromone update operator was designed to integrate energy consumption and hops into routing choice. Finally, with the results of the multiple simulations we were able to show that LTAWSN, in comparison with the previous ant colony based routing algorithm, energy aware ant colony routing algorithms for the routing of wireless sensor networks, ant colony optimization-based location-aware routing algorithm for wireless sensor networks and traditional ant colony algorithm, increase the efficiency of the system, obtains more balanced transmission among the nodes and reduce the energy consumption of the routing and extends the network lifetime.     

A survey of routing techniques for mobile communications networks

Mobile wireless networks pose interesting challenges for routing system design. To produce feasible routes in a mobile wireless network, a routing system must be able to accommodate roving users, changing network topology, and fluctuating link quality. We discuss the impact of node mobility and wireless communication on routing system design, and we survey the set of techniques employed in or proposed for routing in mobile wireless networks.     

QoS-aware routing in emerging heterogeneous wireless networks[Quality-of-Service-Based Routing Algorithms for Heterogeneous Networks]

The integration of different kinds of wireless mobile networks, or heterogeneous wireless networks (HWNs), is emerging. However, a systematic discussion with regard to the special requirements and the complexity of QoS-aware routing in such networks and how QoS is blended with routing is still largely missing. This article aims to cast some light on these aspects. Based on an analysis of the basic architecture of an emerging heterogeneous wireless network and its new requirements on QoS-aware routing, a policy-based QoS supporting system infrastructure and a QoS-aware routing algorithm called QRA are presented in this article. The presentation is specifically given to these issues and components that are unique to HWNs and its QoS routing. The evaluation results show the impact of different network parameters on the performance of QoS-aware routing in HWNs     

无线多媒体传感器网络路由协议研究

传统的无线传感器网络(Wireless Sensor Networks,WSNs)路由协议不能很好地适应多媒体数据流的传输.近来,提出了一些无线多媒体传感器网络(Wireless Multimedia Sensor Networks,WMSNs)路由协议.本文首先讲述了WMSNs服务质量保障路由问题及其面临的挑战,从五...     

On Routing in Multichannel Wireless Mesh Networks: Challenges and Solutions

Wireless mesh networks have emerged as a promising solution to providing cost-effective last-mile connectivity. Employing multiple channels is shown to be an effective approach to overcoming the problem of capacity degradation in multihop wireless networks. However, existing routing schemes that are designed for single-channel multihop wireless networks may lead to inefficient routing paths in multichannel WMNs. To fully exploit the capacity gain due to multiple channels, one must consider the availability of multiple channels and distribute traffic load among channels as well as among nodes in routing algorithms. In this article we focus on the routing problem in multichannel WMNs. We highlight the challenges in designing routing algorithms for multichannel WMNs and examine existing routing metrics that are designed for multichannel WMNs, along with a simulation-based performance study. We also address some open research issues related to routing in multichannel WMNs.     

无线Ad Hoc网络中的QoS路由协议

无线Ad Hoc网络的应用环境以及与Internet的互连都要求其必须提供一定的服务质量(QoS)保证,QoS路由技术是在无线Ad Hoc网络中实现QoS的重要方法。本文对近年来国内外在无线Ad Hoc网络中的QoS路由技术方面取得的研究成果进行了全面的概括总结和分类,对资源预留路由、多径路由和跨层优化路由3类QoS路由协议进行比较分析,并且提出了QoS路由技术亟待解决的问题和今后的发展方向。     

无线Mesh网路由协议仿真及性能分析

当前对无线网格网络（Mesh网络）主要研究之一是无线路由技术,即针对无线Mesh网络自身的特点进行路由设计。在熟悉基于Linux平台的网络仿真器（NS2）针对Mesh网络路由协议的仿真过程的基础上,利用NS2网络仿真软件分别从端到端平均时延、分组递交率、归一化路由开销三个方面比较了目前三种典型的路由协议——按需平面距离矢量路由（AODV）、动态源路由（DSR）和目的序列距离矢量路由（DSDV）的性能,并详细介绍了整个仿真过程的步骤。最后,通过分析AODV协议的吞吐量,得出网络最佳容纳的节点数,研究成果对协议的实现具有重要的应用价值。