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1.
基于位置的Ad Hoc路由协议因其消除了对拓扑存储的依赖性,降低了相关能耗,提升了网络性能,成为了学者们重点关注的研究领域。介绍了基于位置的Ad Hoc路由协议的概念,分析了几个典型的基础路由协议,总结了现阶段研究面临的问题,归纳了基于地理位置路由协议国内外研究现状及发展趋势。 相似文献
2.
基于距离向量的按需路由协议AODV是移动Ad Hoc网络研究的热点之一.文中提出一种基于AODV的分簇路由协议CAODV,该协议通过增加分簇机制,将AODV协议改进为层次型的路由协议.与AODV协议仿真比较后可以看出,改进后的CAODV协议在分组转发率和路由开销方面的性能有较大提高. 相似文献
3.
基于终端的LEO/Ad Hoc网络双模组网模型,分析在LEO卫星通信系统业务溢出情况下地面终端组织Ad Hoc网络的路由查找算法问题,提出一种利用高层LEO卫星通信系统供给的地理信息和信令支持下的路由算法(Geographic Location Based Route,GLBR),通过仿真实验验证了其有效性。 相似文献
4.
在真实的无线传感网络(WSNs)应用环境中,传感节点位于三维空间。为此,提出基于锥形转发区域的三维地理位置路由协议。为了减少冗余数据包数、降低数据包碰撞概率,CFRG协议先建立锥形转发区域,其目的在于限制转发节点数。然后,再估计锥形转发区域内节点的转发概率,最终选择具有最大转发概率的节点转发数据包。当节点遭遇空洞节点问题,就自适应地调整锥形转发区域体积,扩大选择转发节点的空间,即通过锥形转发区域调整,解决VNP问题。仿真结果表明,提出的CFRG协议能够处理VNP问题。与同类的三维路由协议相比,CFRG协议能够提升端到端传输时延和数据包丢失率两方面性能。 相似文献
5.
提出了一种适用于非对称链路的Ad Hoc网络路由协议。该协议是一种基于路由池的反应式路由协议,当源节点与目标节点有数据交换时,通过路由发现过程分别在源节点和目标节点构建数据路由池和应答路由池,数据的发送和应答路径随机地从相应路由池中选取,并在数据的交换的过程中动态地更新和维护路由池。仿真结果表明该协议适用于普遍存在非对称链路的无线移动Ad Hoc网络。 相似文献
6.
目的是对Ad Hoc网络中按需路由协议DSR进行改进以提高网络的数据通信的实时性.通过对DSR协议中的路由维护和路由表存储机制进行改进来完成降低网络时延的目的,并在OPNET上进行仿真实验.分别比较了普通DSR协议,带多条备用路由的DSR协议和本文提出改进型路由维护的DSR协议进行仿真,比较三种协议下网络平均传输时廷.仿真实验证明,改进的路由协议对降低网络平均时延是行之有效的. 相似文献
7.
针对移动Ad Hoc网络中节点任意移动、网络拓扑频繁变化导致以最小跳数作为路由选择机制的AODV路由协议面临频繁连接中断而造成网络QoS下降的问题,文章综合节点的剩余电量、剩余队列长度和源节点到目的节点的跳数三个跨层信息,提出一种基于灰色关联算法的改进AODV路由协议(GRA-AODV)。仿真结果显示:相比于改进前的AODV协议,改进之后的GRA-AODV(Gray Relevance AlgorithmAODV)协议在稍微增加路由开销的情况下,具有更低的平均端到端时延和更低的分组丢失率,在拓扑频繁变化的移动Ad Hoc网络中具有较好的鲁棒性。 相似文献
8.
传统的AM解调采用包络检波方法,其输入信号为含有载波的已调信号。随着DDC技术的出现和发展,在基带上对AM进行解调成为可能。文章提出了一种基于CORDIC算法的AM基带解调方法,仿真结果证明了此方法的可行性。 相似文献
9.
介绍了基于负载均衡的动态负载感知路由协议(DLLMR)的工作过程,DLLMR协议对DSR协议进行了3个方面的改进:①避免了负载较重的路径上继续增加业务量;②均匀地分配网络中的业务流;③减小了由于重新发起路由发现过程带来的开销和时延。最后介绍了以负载、时延为尺度的路径优劣判定准则。 相似文献
10.
针对Ad Hoc网络拓扑变化频繁及节点能量有限的问题,提出基于ODMRP的稳定节能路由协议SEE-ODMRP,通过贪婪转发机制建立主路径,在综合考虑路径保持连接时间和节点剩余能量的基础上,引入路径质量模型建立备用路径,实现节点能耗的最小化,从而提高协议的鲁棒性.理论分析和仿真结果证明了该协议的有效性. 相似文献
11.
Ad hoc网络是一些移动节点组成一个多跳的临时性无线自治系统,这种新型的通信网络具有动态变化的拓扑结构和分布控制的网络机制。文中针对Ad hoc网络作了简单的介绍并重点介绍了针对Ad hoc网络特性而提出的路由协议。 相似文献
12.
In this paper we present a scalable routing protocol for ad hoc networks. The protocol is based on a geographic location management strategy that keeps the overhead of routing packets relatively small. Nodes are assigned home regions and all nodes within a home region know the approximate location of the registered nodes. As nodes travel, they send location update messages to their home regions and this information is used to route data packets. In this paper, we derive theoretical performance results for the protocol and prove that the control packet overhead scales linearly with node speed and as N
3/2 with increasing number of nodes. These results indicate that our protocol is well suited to relatively large ad hoc networks where nodes travel at high speed. Finally, we use simulations to validate our analytical model. 相似文献
13.
移动自组网备受关注的同时也暴露了其在某些方面的局限性,尤其是能量、带宽问题,因此有必要设计最佳路由协议来减少能量消耗、缩短路由、限制泛播,介绍了2种自适应的、无链接的路由协议及其子系统。当采用定向天线时,该协议能减少在分组传送过程中涉及的节点数量,因此减少了能量消耗,充分利用带宽。 相似文献
14.
考虑到城市环境中障碍物对网络性能的重要影响,在NS2(Network Simulator version 2)中加入了代表障碍物的概率穿透模型,使仿真环境更接近真实环境。针对AODV(Ad hoc On-Demand Distance Vector Routing)协议应用在城市场景下的缺陷,提出了一种改进的AODV协议——GE-AODV(Geocast Enhanced AODV)协议,该协议是基于位置信息的协议,并采用了多播方式来转发控制信息。仿真表明,GE-AODV降低了网络时延和控制开销,提高了网络可靠性。 相似文献
15.
移动Ad Hoc网络是一个自组织、移动节点通过无线链路组成的动态拓扑变化的网络。由于网络规模小、无基础设施构建快速等特点,从而广泛应用于灾难救助、临时会议、战场指挥等场合。这些应用都涉及到移动Ad Hoc对组播的支持,因此,随着网络应用规模的增长,移动Ad Hoc网络对组播的支持成为一个重要的研究课题。本文对目前的组播路由机制进行了分类和研究,详细描述和比较了这些移动Ad Hoc网络组播路由协议,为组播路由协议和算法进一步的研究提出了新的课题。 相似文献
16.
应用于战术条件下的自组织网络,其拓扑具有长期稳定而短期突变的特性;其流量具有不均衡性,中心节点的流量比重较大.针对战术无线网络的这种特性设计了一种混合式路由协议(HRP),协议为近端节点采用先应式协议维护路由而为远端节点采用反应式协议维护路由,对远端节点的路由请求采用OLSR协议的MPR思想,限制反应式协议的路由开销.并且,在近端拓扑变化频度超过门限值后,发起针对繁忙节点的路由发现请求,保持到繁忙节点的路由常新,从而提高了路由命中率.仿真结果表明,应用HRP协议后,无论其选路质量还是应用层业务的时延和吞吐量指标都优于DSR和ZRP协议. 相似文献
17.
A new dynamic relationship-zone routing protocol (DRZRP) for ad hoc networks is proposed. In this protocol, each node in the network establishes a neighboring-zone with a radius of ρ hops, and activates a relationship-zone according to the service request frequency and service hotspot condition. DRZRP establishes proactive routing for neighboring-zone and relationship-zone of the node, and the relationship-zone of the node can be dynamically maintained, including: initialization, relationship-zone activation, and relationship-zone inactivation. The simulation results are compared with LSR, ZRP and ZHLS protocols, and DRZRP greatly reduces the communication overhead of routing control messages and significantly improves the average delay of routing requests. The new protocol matches the service relationship among nodes in the network, and has comprehensive performance advantage in communication overhead and routing request delay, which improves the quality of network service. 相似文献
18.
针对移动Ad Hoc网络,研究了一种多路径的路由算法。该算法是在AODV算法基础上建立起来的,有效地利用了AODV算法中中间节点接收到的重复的RREP建立起多路径的路由,其优点是当一条链路失败时,节点可以从后备链路中选取一条而不会影响到其他的链路通信。并且当路由发生断裂后,该算法可以尽可能地进行本地修复,以保证多路径的数据通信。仿真结果表明建议的路由算法在路由延迟等方面比现有的AODV路由算法有更好的性能。 相似文献
19.
The main purposes of this article are to relieve broadcast problem, to immunize to some prerequisites, and to reduce the number of transmitted control packets. Broadcasting control packets network-wide is the most direct and common method for finding the required destination node in ad hoc mobile wireless networks; however, this causes a lot of waste of wireless bandwidth. To remedy the problem, routing protocols demanding some prerequisites are proposed; nonetheless, hardly can they be used if these prerequisites are missed or become stale. To efficiently reduce the number of transmitted control packets, our routing protocol partitions the network into interlaced gray districts and white districts by the aid of GPS and inhibits an intermediate node residing in a white district from re-transmitting the received control packets. However, a mobile node residing in a gray district is responsible for re-transmitting them till they reach the destination node. Our routing protocol does not demand any prerequisite except the use of GPS. Each mobile node can always obtain its own location information; furthermore, the information may neither be missed nor become stale. Our routing protocol is easy to be implemented, saves precious wireless bandwidth, and reduces almost half a number of control packets as compared with pure flooding routing protocols. Ying-Kwei Ho received the B.S. degree and M.S. degree in applied mathematics and in electrical engineering from the Chung-Cheng Institute of Technology in 1987 and 1993 respectively and the Ph.D. degree in computer engineering and science from the Yuan-Ze University, Taiwan, R.O.C. He joined the Army of Taiwan, R.O.C. in 1987 and worked as a software engineer. From 1993 to 1997, he was an instructor in the War Game Center of Armed Forces University, Taiwan, R.O.C. He is currently an assistant professor of the Department of Computer Science at Chung-Cheng Institute of Technology. His research interests include mobile computing, wireless network performance simulation and evaluation, and modeling and simulation. Ru-Sheng Liu received the B.S. degree in electrical engineering from the National Cheng-Kung University, Taiwan, in 1972 and the M.S. and Ph.D. degrees in computer science from the University of Texas at Dallas, Richardson, Texas, in 1981 and1985, respectively. He is currently an associate professor in the Department of Computer Engineering and Science at Yuan-Ze University, Chungli, Taiwan. His research interests are in the areas of mobile computing, internet technology, and computer algorithms. 相似文献
20.
Ad Hoc网络中的节点是由电池供电,整个网络是一个能量受限系统,如何节省节点的能量,尽可能延长网络的可操控时间逐渐成为衡量路由协议性能的重要指标.基于移动节点能量的不同级别,采取不同的转发策略,提出了一种基于能量感知的Ad Hoc网络路由协议--EARP.并与AODV协议进行了性能比较,仿真结果显示,EARP具有较低的能耗,较长的网络存活时间. 相似文献
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