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随着无线通信的日益发展,无线自组织网络正逐渐从军用扩大到民用等诸多领域。但是无线自组织网络一般由电池供电,由于提高电池容量的技术进步缓慢,功率控制是一个重要的研究课题。无线自组织网络中的功率控制机制研究主要集中在3个方面,即网络层功率控制、链路层功率控制以及混合功率控制。重点是从分层的角度对功率控制进行阐述,主要介绍了网络层及链路层的功率控制,并介绍了一些节能协议。跨层设计综合考虑了各层性能能更好地为功率控制与节能服务。 相似文献
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移动自组网中各移动节点的能量消耗比较大,而大多数节点都是由有限寿命的电 池来提供的,因此在制定路由协议时必须考虑其能量保护。拓扑控制算法通过控制结点的传 输范围使生成的网络拓扑满足一定的性质,以延长网络生命周期,降低网络干扰。详细分析了 cone-based拓扑控制算法(CBTC),及其进行改进以适应自组网移动性的特点。 相似文献
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移动自组网IP地址分配技术综述 总被引:1,自引:0,他引:1
对近年来提出的多种移动自组网(MANET)地址分配技术进行了较详细地分类评价和性能比较,包括基于状态维护的算法,基于冲突检测的算法和基于网络分层的算法等,并在最后指出了未来的技术发展方向。 相似文献
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为满足基于TDD同步调度机制的移动自组网设计方案中网络层路由算法与MAC层调度协议处理需求,构建了基于S3C6410 ARM处理器与TMS320C6416 DSP处理器的多核构架的移动自组网节点路由与调度处理单元,并给出了基于HPI接口的多处理器层间数据交互硬件设计方案与软件设计架构。实现结果证明HPI接口可靠、稳定,满足自组网节点层间高速数据传输要求。 相似文献
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以优化的链路状态路由(Optimized Link State Routing,OLSR)协议为原型,为无线移动自组织网络(Mobile Ad Hoc Networks,MANETs)设计了基于跨层的速率自适应的加权路由协议。该协议充分考察无线信道的时变性质,在路由计算过程中通过跨层信息共享节点的邻居关系及获取节点的当前发送速率,削减了协议的开销。将无线链路的速率与跳数相结合,设计了一种新的路由度量规则。仿真结果表明,提出的加权路由协议能够显著降低网络层的路由开销,提升网络吞吐量,降低端到端时延。 相似文献
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移动自组网(MANET)是新型的无线移动网络,它不依赖固定网络设施,是能快速展开、自治、多跳的网络结构。它由一组带有无线收发装置的节点组成,整个网络通过移动节点间的相互协作保持网络互联。网络中的每个节点都能快速移动,同时具备主机和路由器功能。移动自组网的前身是分组无线 相似文献
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引入数字多波束技术可以使移动自组织网络的信道容量得到有效提升,然而,时间、频率、空间、用户、功率等多维度资源域的统一调度与跨层联合优化使得信道接入机制的分析与设计变得更加复杂。为此,结合多波束的特性,将波束宽度限制、收发限制、通道限制、功率限制等多种约束条件抽象图论问题,并建立分析模型。基于分析模型,进一步提出了MB-MAC(Multi-beam Medium Access Control)信道接入机制,结合物理层的预编码技术,建立定向链路的队列模型,度量用户的满意度(Quality of Experience,QoE),设计了适用于自组织网络中多用户并发并收的信道接入机制,兼顾了网络容量和用户满意度。仿真结果表明,MB-MAC机制能在保证各个用户满意度的情况下,有效提升网络吞吐率。 相似文献
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Although establishing correct and efficient routes is an important design issue in mobile ad hoc networks (MANETs), a more challenging goal is to provide energy efficient routes because mobile nodes' operation time is the most critical limiting factor. This article surveys and classifies the energy‐aware routing protocols proposed for MANETs. They minimize either the active communication energy required to transmit or receive packets or the inactive energy consumed when a mobile node stays idle but listens to the wireless medium for any possible communication requests from other nodes. Transmission power control approach and load distribution approach belong to the former category, and sleep/power‐down mode approach belongs to the latter category. While it is not clear whether any particular algorithm or a class of algorithms is the best for all scenarios, each protocol has definite advantages/disadvantages and is well suited for certain situations. The purpose of this paper is to facilitate the research efforts in combining the existing solutions to offer a more energy efficient routing mechanism. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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In this paper, we present a Petri net model for performance evaluation of IEEE 802.11 distributed coordination function as a popular media access control layer protocol in mobile ad hoc network. The goal of this evaluation is to examine this protocol under the existing of misbehavior nodes that selfishly try to grasp common channel in a neighbor area. The presented model consists of 2 separate models based on stochastic reward net (SRN), as a variation of stochastic Petri net. The first model, which is called one node operation model , is supposed for presenting all distributed coordination function operations in a single node such as collision avoidance, request to send/clear to send (RTS/CTS) handshake, and backoff mechanism. The next SRN model, all node operation model , is used for modeling nodes competition for occupying channel in a neighbor area. The models could be adjusted to a dynamic network with any number of nodes, dimension scale, and nodes' speed. For evaluation purpose, 4 distinct attack types implemented by modifying associated transitions in SRN models. The proposed SRN model has been quantified by deriving 2 performances metrics as Throughput and Delay . Both metrics are also compared to the value obtained from NS‐2 in terms of different number of nodes and 3 packet generation rates. Three additional metrics measuring the channel usage are also quantified in terms of different attack strategies using only presented SRN model. 相似文献
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Sanjay Kumar Dhurandher Sudip Misra Mohammad S. Obaidat Vikrant Bansal Prithvi Raj Singh Vikas Punia 《International Journal of Communication Systems》2009,22(7):789-817
Mobile ad hoc networks (MANETs) are characterized by random, multi‐hop topologies that do not have a centralized coordinating entity or a fixed infrastructure that may change rapidly over time. In addition, mobile nodes operate with portable and finite power sources. In this work, we propose an energy‐efficient routing protocol for MANETs to minimize energy consumption and increase the network's consistency. Traditional works mainly focused on the shortest path‐based schemes to minimize energy, which might result into network failure because some nodes might exhaust fast as they are used repetitively, while some other nodes might not be used at all. This can lead to energy imbalance and to network life reduction. We propose an energy‐efficient ad hoc on‐demand routing protocol that balances energy load among nodes so that a minimum energy level is maintained among nodes and the network life increases. We focused on increasing the network longevity by distributing energy consumption in the network. We also compared the simulation results with a popular existing on‐demand routing protocol in this area, AODV, to establish the superiority of our approach. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Yunfeng Peng Riheng Jia Xing Gao Xiaoying Gan 《Wireless Communications and Mobile Computing》2016,16(15):2287-2297
With the prevalence of mobile devices, it is of much interest to study the properties of mobile ad hoc networks. In this paper, we extend the concept of diameter from static ad hoc network to mobile ad hoc network, which is the expected number of rounds for one node to transmit a message to all other nodes in the network, reflecting the worst end‐to‐end delay between any two node. Specifically, we investigate the diameter of identically and independently mobility model in cell‐partitioned network and random walk mobility model in two‐dimensional torus network, achieving the boundary , when (k=Ω(n)), and O(k log2k), respectively, where n is the number of nodes and k is the number of cells of network and especially under random walk mobility model . A comparison is made among the diameter of mobile ad hoc networks under identically and independently mobility model, random walk mobility model and static ad hoc network, showing that mobility dramatically decreases the diameter of the network and speed is an essential and decisive factor of diameter. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Chen Chen Lin Bai Kai Cai Jianhua He Haige Xiang 《Wireless Communications and Mobile Computing》2010,10(8):1017-1032
The performance of wireless networks is limited by multiple access interference (MAI) in the traditional communication approach where the interfered signals of the concurrent transmissions are treated as noise. In this paper, we treat the interfered signals from a new perspective on the basis of additive electromagnetic (EM) waves and propose a network coding based interference cancelation (NCIC) scheme. In the proposed scheme, adjacent nodes can transmit simultaneously with careful scheduling; therefore, network performance will not be limited by the MAI. Additionally we design a space segmentation method for general wireless ad hoc networks, which organizes network into clusters with regular shapes (e.g., square and hexagon) to reduce the number of relay nodes. The segmentation method works with the scheduling scheme and can help achieve better scalability and reduced complexity. We derive accurate analytic models for the probability of connectivity between two adjacent cluster heads which is important for successful information relay. We proved that with the proposed NCIC scheme, the transmission efficiency can be improved by at least 50% for general wireless networks as compared to the traditional interference avoidance schemes. Numeric results also show the space segmentation is feasible and effective. Finally we propose and discuss a method to implement the NCIC scheme in a practical orthogonal frequency division multiplexing (OFDM) communications networks. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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We consider the problem of localized energy aware routing in mobile ad hoc networks. In localized routing algorithms, each node forwards a message based on the position of itself, its neighbors and the destination. The objective of energy aware routing algorithms is to minimize the total power for routing a message from source to destination or to maximize the total number of routing tasks that a node can perform before its battery power depletes. In this paper we propose new localized energy aware routing algorithms called OLEAR. The algorithms have very high packet delivery rate with low packet forwarding and battery power consumption. In addition, they ensure good energy distribution among the nodes. Finally, packets reach the destination using smaller number of hops. All these properties make our algorithm suitable for routing in any energy constrained environment. We compare the performance of our algorithms with other existing energy and non‐energy aware localized algorithms. Simulation experiments show that our algorithms present comparable energy consumption and distribution to other energy aware algorithms and better packet delivery rate. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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Christian Lochert Bjrn Scheuermann Martin Mauve 《Wireless Communications and Mobile Computing》2007,7(5):655-676
Congestion control is a key problem in mobile ad hoc networks. The standard congestion control mechanism of the Transmission Control Protocol (TCP) is not able to handle the special properties of a shared wireless multi‐hop channel well. In particular, the frequent changes of the network topology and the shared nature of the wireless channel pose significant challenges. Many approaches have been proposed to overcome these difficulties. In this paper, we give an overview over existing proposals, explain their key ideas and show their interrelations. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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黄成兵 《智能计算机与应用》2016,(5)
介绍移动自组网的特点、发展与现状,并与现有通信手段进行分析对比,指明移动自组网在各类灾后营救中的相比传统通信手段所更能发挥的积极作用,展望移动自组网在各个领域中的应用前景。 相似文献