无线Mesh网络一种以节点为单位的多信道分配

在无线Mesh网络中,利用无线多信道路由协议可以提高网络的性能,因此信道资源的分配与管理对于无线Mesh网的性能优化起着十分重要的作用。本文介绍了一种以节点为单位进行信道分配的算法。     

无线Mesh网络集中式信道分配算法设计

以集中式无线Mesh网络(WMN)为基础,分析和研究了传统多信道分配算法,并在此基础上提出了以节点优先级和分组为特点的多接口多信道分配算法(Channel Assignment based on Rank of Node and Link group,CAR-NL),该算法结合节点分级和链路负载预期评估机制,通过节点链路分组按级分配信道。通过仿真实验表明,该算法能有效提高无线Mesh网络多业务流并发执行时系统整体吞吐量,并实现较低的丢包率。     

一种新的基于最大流的无线Mesh网络信道分配算法

在无线Mesh网络中,为节点配置多接口多信道MAC协议成为提高网络性能、扩大网络容量的有效手段之一。有效的信道分配策略在多信道无线Mesh网络中显得尤为重要。本文提出一种基于最大流的信道分配算法。该算法通过最大流计算网络中可达到的最大吞吐量,以此作为网络负载标准进行信道分配,将降低整个网络的总体干扰作为目标函数进行优化。仿真结果表明,即使在网络负载较重的情况下,算法仍能保持较好的性能。     

多信道无线Mesh网络的性能研究

在无线Mesh网络中使用多信道可以减少碰撞和干扰,提高系统吞吐量。本文先介绍无线Mesh网络,然后介绍多信道在无线Mesh网络中的应用,分析了几种常用的多信道MAC协议。接着着重阐述了多信道无线Mesh网络所面临的问题与挑战,对信道分配、路由选择和隐蔽终端这3个主要问题进行分析,并对其研究设计方向进行了展望。     

智能家居中无线Mesh网络信道分配算法的研究

将无线Mesh网络技术应用于智能家居组网中对实现信息化、网络化智能家居系统具有重要意义。针对现有无线Mesh网络信道分配算法无法满足智能家居系统中网络连接稳定性、灵活性等需求的问题,提出了一种基于信道状态的动态信道分配算法。该算法利用控制信道交互的信息,通过Hello信息的交换、信道协商、数据传输三个主要步骤实现动态分配信道,有效提高了无线Mesh网络的稳定性。     

多射频无线Mesh网中的接口分域信道分配

在多射频多信道无线Mesh网中,是无线宽带接入的重要候选技术之一.为了满足无线宽带接入的容量要求,Mesh路由器节点常需要配置多个无线接口并使用多个正交信道.已有的信道分配方法虽能减少干扰和碰撞,但不能完全避免.本文提出一种域内中心式调度的接口分域信道分配(ICCA)方案,旨在完全避免干扰与碰撞以提高网络吞吐量,尤其能...     

无线 Mesh 网络部分重叠信道分配综述

无线Mesh网络面临的主要挑战是由共信道干扰导致的网络容量下降问题,仔细规划部分重叠信道的使用能减少甚至消除共信道干扰。在介绍部分重叠信道基本概念的基础上,重点从单播和多播2个角度对国内外部分重叠信道分配研究领域的成果进行了分类总结与分析;深入剖析部分重叠信道分配中的难点与挑战,并展望了未来的研究方向,以期促进无线Mesh网络向“最后一公里”接入的理想解决方案演进。     

基于拓扑分割的无线Mesh网络信道分配策略

该文根据无线Mesh网络流量呈现树状拓扑汇聚的特点提出基于拓扑分割的信道分配策略。依据无线干扰对不同链路的影响程度,把无线干扰分类为有确定方向的纵向干扰和横向干扰;提出沿着纵向干扰方向逐跳分割网络拓扑算法;提出最少信道隔离纵向干扰和为吞吐量最小的子拓扑增加信道的子拓扑间信道分配策略;提出横向干扰分块的子拓扑内信道使用方法;理论分析子拓扑内的冲突域及网络性能瓶颈,仿真研究子拓扑的吞吐性能及信道分配顺序。仿真结果表明,隔离纵向干扰和增加信道的分配策略能够有效保证和提升网络吞吐量,横向干扰分块的方法优于802.11s中定义的公共信道框架多信道机制。     

一种基于博弈论的无线Mesh网信道分配算法

为解决无线Mesh网络中的信道分配问题,提出了基于博弈论的信道分配(GBCA)算法。该算法将无线Mesh网中各节点的信道分配过程作为一个博弈过程,信道分配策略作为博弈者的策略选择,信噪比函数为博弈的效用函数。基于NS2的仿真结果表明该算法在吞吐量和丢包率方面都有较好的性能。     

无线Mesh网络多信道MAC协议

分析了WMN多信道MAC协议设计所面临的问题;介绍了几种现有典型的多信道MAC协议,并对其进行了分析;对多信道MAC协议未来的发展作了简要的总结。期望文章使读者对WMN多信道MAC协议的关键技术,特别是协议的设计有一个概括性的了解。     

无线MESH网络中的多信道MAC协议概述

分析了无线mesh网络多信道应用的必要性;介绍了多信道应用的现状,列出了几种典型的多信道协议;对各种多信道协议进行了分析,总结了其优缺点;提出对多信道未来改进方向的看法.     

Fair Allocation of Subcarrier and Power in an OFDMA Wireless Mesh Network

This paper presents a new fair scheduling scheme for orthogonal frequency-division multiple-access-based wireless mesh networks (WMNs), which fairly allocates subcarriers and power to mesh routers (MRs) and mesh clients to maximize the Nash bargaining solution fairness criterion. In WMNs, since not all the information necessary for scheduling is available at a central scheduler (e.g., MR), it is advantageous to involve the MR and as many mesh clients as possible in distributed scheduling based on the limited information that is available locally at each node. Instead of solving a single global control problem, we hierarchically decouple the subcarrier and power allocation problem into two subproblems, where the MR allocates groups of subcarriers to the mesh clients, and each mesh client allocates transmit power among its subcarriers to each of its outgoing links. We formulate the two subproblems by nonlinear integer programming and nonlinear mixed integer programming, respectively. A simple and efficient solution algorithm is developed for the MR's problem. Also, a closed-form solution is obtained by transforming the mesh client's problem into a time-division scheduling problem. Extensive simulation results demonstrate that the proposed scheme provides fair opportunities to the respective users (mesh clients) and a comparable overall end-to-end rate when the number of mesh clients increases     

Joint Algorithm of Channel Allocation and Power Control in Multi-channel Wireless Sensor Network

In the wireless sensor network, the interference incurred by another transmitter’s transmission may disturb other receivers’ correct receptions of packets, thus, the add of a new transmission must consider its effect on other transmissions. Additionally, in order to reduce the interference and increase QoS, multi-channel technology is introduced into wireless communication, but the energy cost by the channel switch increases with the interval of channels increasing. Based on the above analysis, we consider an energy efficient joint algorithm of channel allocation and power control (JCAPC) for wireless sensor network. In JCAPC, each link firstly establishes its available channel set on which the transmitter of the link can guarantee its transmission successfully and don’t disturb other receivers’ transmissions, and then each link chooses a channel from the available channel set according to the energy cost on anti-interference and channel switch. After that, we formulate power control on each channel as a non-cooperative game with utility function including Signal-to-Interference-and-Noise Ratio (SINR) price. In order to reduce the energy cost of the information exchange during the traditional game, we introduce the thought of game virtual playing, in which each link can decide its own transmission power by imitating the game among links with its once collected information. Consequently, JCAPC can not only increase the transmission efficiency but also reduce the nodes’ energy waste. Moreover, the existence of Nash Equilibrium (NE) is proven based on super-modular game theory, and it’s able to obtain the unique NE by relating this algorithm to myopic best response updates. The introduction of game virtual playing saves the energy cost of network further more by reducing the number of information exchange. Simulation results show that our algorithm can select a channel with good QoS using less energy consumption and provide adequate SINR with less transmit power, which achieves the goal of efficiently reducing energy waste.     

Joint Subchannel,Rate and Power Allocation in OFDMA-Based Cognitive Wireless Mesh Network

In this paper, the problem of resource allocation in an Orthogonal Frequency Division Multiple Access-based Cognitive Wireless Mesh Network (CWMN) is addressed. The objective is to maximize the total utilities in a CWMN, which is defined as any increasing, concave and twice differentiable function of the end-to-end flow rate, by jointly allocating each link’s rate, power and subchannels under the constraints of multiple primary users’ Interference Temperature and multiple access interference. First, a centralized resource allocation algorithm is developed based on the Column Generation approach, and shown to be optimal. So it can perform as a criterion for designing other algorithms. Secondly, considering the applicability of algorithm in distributed system, a near-optimal distributed algorithm is proposed, which allocates subchannel based on routing information at first, and then jointly allocates the resource of rate and power. Finally, the simulation results validate the centralized and distributed algorithms, and show that better performance can be achieved than the conventional algorithm.     

无线协作Mesh网

异构无线网络的融合是当前无线网络的发展趋势。针对融合过程中遇到的诸如传输模式选择、负载平衡、路由和切换之类的问题,文章提出了一种新的网络融合架构：无线协作Mesh网。该架构基于无线Mesh网的网络结构,并通过协作通信进一步优化其结构、提升其性能。该架构能充分发挥Mesh技术高频谱效率、动态自组织的优点和协作通信高分集增益、高能量效率的优点,可为无线网络融合提供一种有效的解决方案。     

基于单射频的无线Mesh网多信道方法

无线网状网(Wireless Mesh Network,WMN)是一种新型的分布式宽带无线网络结构.典型的移动Ad Hoc网络具有节点移动性小、受电池动力限制和用户带宽需求大等特点,从而导致传统单信道的Ad Hoc结构不再满足WMN用户的需求.为了提供更大的带宽,多信道技术得到越来越多应用.探讨了WMN的网络结构与特点,对现有几种典型的多信道技术进行了比较,提出了一种基于单射频的无线Mesh网多信道的设计方案,不同网关节点所代理的节点使用不同的信道进行通信,从而避免了不同子网节点之间的信道干扰.通过NS2的仿真与分析表明,该方法在特定环境下的网络性能是传统单射频单信道方法的2倍.     

基于网络编码多维特征权重的无线Mesh网络接入时间分配机制

本文分析影响系统接入时间分配决策的多种因素,提出基于网络编码多维终端特征权重模型的系统接入时间分配机制FDMW.FDMW构建终端编码集合信道多维特征权重模型,自适应调整系统接入时间分配决策.理论和仿真证明,FDMW能够动态优化接入时间,有效提升系统整体传输效率.     

无线Mesh网络流量自相似性研究

近年来,无线Mesh网络已成为一个倍受关注的研究领域.对无线Mesh网络流量特性的研究将有助于网络协议的研究、评估,以及网络结构的规划和建设.本文通过对无线Mesh测试网上采集的数据包进行统计分析,揭示了网络流量具有自相似的特性.同时,解释了无线Mesh网络流量自相似性是由网络中具有重尾分布特性的多个流叠加形成的,并通过仿真进一步分析了节点移动性对流量自相似性的影响.