物联网感知层移动自组织网可靠性评估方法

移动自组织网可靠性是影响物联网应用的数据采集和设备控制的关键因素之一。为解决移动自组织网络可靠性的不确定性分析和量化评估的问题,综合考虑节点移动性引起的动态连接以及网络组件故障的因素,提出了一种基于节点移动的Ad_hoc网的可靠性计算方法。在两个节点移动时都保持速度和方向不变的条件下,首先预测其中一个节点有效链路保持的持续时间,然后考虑此节点某段时间内在速度和方向上的变化来评估此链路的有效性,进而间接地计算自组织网的可靠性。实验结果表明,移动自组织网的可靠性不仅依赖节点、链路可靠性,还依赖于网络拓扑的冗余度和节点在网络中的分布。     

异构传感器网络节点部署算法

传感器节点的部署方式有确定性的和自组织两种。研究了由高级节点和普通节点组成的异构传感器网络的节点部署问题。给出一种满足连通覆盖条件的最大化网络寿命模型,通过分析节点的能量消耗,计算出了最大化网络寿命时两种节点的部署比例,提出了最大化网络寿命的节点部署算法。     

移动自组网中能量优化的路由算法研究综述

移动自组网是在没有中心基础设施情况下由一些移动用户自组织形成的多跳无线移动网络,通常为一些特殊环境提供临时通信便利.由于移动自组网中终端设备依赖于电池供电,为了延长节点的工作时间,要求尽量减少节点的能量消耗,从而延长整个网络的使用寿命.本文对当前存在的基于能量优化的单播和组播路由算法进行了分析和比较,阐述了目前亟待解决的主要问题和今后的研究方向.     

基于双重虚拟力算法的移动自组织网络节点移动策略研究

针对自组织网络中节点移动过程所带来的不确定性,本文提出一种基于双重虚拟力算法的节点移动策略,提升网络整体性能。首先,本文建立节点模型分析节点的基本移动方式与能量消耗方式;然后,设定阈值参数建立“距离虚拟力”与“能量虚拟力”双重虚拟力模型,制定节点移动策略。数值仿真结果显示:提出的移动策略可以有效提高网络整体覆盖率、节点连通率;对比单一指标的虚拟力模型,双重虚拟力模型可以降低网络能耗,提高网络生存时间。     

无线传感器网络中数据量转移的能量均衡策略

无线传感器网络中各节点能耗不均衡严重影响了网络的生命周期。首先通过理论分析得出了圆形区域网络的数据量转发和能量消耗特性,其次阐述了如何选择最优的发射功率使得网络寿命最长,最后为进一步降低网络能耗,提出了一种有效的数据量转移的能量均衡策略,数值仿真结果证明该策略可以有效降低整网能量消耗,延长网络生存周期。     

移动传感器网络中能量均衡分簇及移动策略

无线传感器网络各节点能量有限,如果数据收集节点（Sink）能够移动,则可以大大节约节点能量,从而延长网络的寿命。首先提出一种能量均衡的分簇算法,根据节点地理信息进行分簇,使得节点耗费总能量尽可能小的同时,使各簇能量消耗基本平衡;在此基础上提出一种Sink 移动策略,Sink 优先选择能量较充足的簇收集信息。仿真结果表明,与传统的随机移动算法相比,提出的算法能够显著平衡各族之间的能量消耗,并减少总的网络能量消耗,从而提高网络的寿命。     

蚁群算法在无线传感器网络中的应用研究

使用无线传感器节点有限的能量保证网络的寿命是无线传感器网络研究的重要问题,网络能量是否均衡消耗对网络寿命有着决定性的影响.为了促使网络节点能量消耗相对均衡,将蚁群优化算法应用于无线传感器网络的路径选择,提出一种蚁群优化的无线传感器网络能量均衡路由算法.利用蚁群的自组织、自适应和动态寻优能力,通过蚂蚁并行地寻找从源节点到达目的节点的最优路径,使网络最优路径和能量均衡消耗之间进行平衡,以达到网络能量的优化均衡消耗,进而延长整个网络的寿命.进行了仿真实验,实验结果表明,与经典路由定向扩散算法相比,算法能有效地均衡网络节点的能量消耗为设计提供了有效的方法.     

无线传感器网络中多移动Agent协同控制数据分流方法

针对移动Agent携带大量的数据包在网络上传输而造成的网络能量消耗过高、延迟时间过长和源节点工作寿命缩短等问题,提出了一种多移动Agent协同控制数据分流方法.首先,对树型结构为基础的多移动Agent行程规划算法进行分析;其次,建立网络能量消耗模型;最后,以能量消耗最小为原则,对树枝分叉处多移动Agent之间的数据和移动Agent迁移过程中的数据量两种情形进行合理分流.利用仿真将该方法与不分流的最小生成树多代理行程规划(MST-MIP)算法进行比较,结果表明该方法在能量消耗和任务延迟方面能够获得更好的性能,能量消耗最多可以降低35.2％,任务执行时间减少14.5％,传感器节点工作寿命也显著提高.     

基于蚁群算法的DSR协议研究与仿真

为了延长无线网络的生存时间,避免簇内过早的出现盲节点,提出了一种利用蚁群算法优化的DSR协议。在划分簇和选择簇头的研究过程中,动态追踪无线网络中节点的变化情况,分权衡量节点的移动速度和剩余能量,选择合适的簇首和稳定的信息传播半径,并根据信息传播半径的大小对传感器节点的地理位置进行虚拟网格划分,最终实现信息的稳定传输和能量的有效利用。仿真结果表明,与LEACH和CDSR协议相比,该算法不仅有效地提高了信息传输效率、均衡了网络节点的能量消耗、延长了网络寿命,并且有效增强了无线自组织网络的鲁棒性。     

基于能量粒子算法的无线自组织网络节点 移动策略研究

借鉴传统的粒子群优化模型,将网络节点类比于具有能量维度的粒子,提出一种能量粒子算法确定节点移动策略。首先,建立节点模型分析节点能量消耗方式。然后,建立节点移动模型,利用邻居节点的剩余能量信息确定节点移动方向与移动速度。最后?,仿真结果显示:相对于传统的节点移动方式。本文所提出的节点移动策略可以有效缓解网络瓶颈节点能量消耗速率,改善网络能耗均衡性,延长网络生存时间。     

A Novel Gradient Boosted Energy Optimization Model (GBEOM) for MANET

Mobile Ad Hoc Network (MANET) is an infrastructure-less network that is comprised of a set of nodes that move randomly. In MANET, the overall performance is improved through multipath multicast routing to achieve the quality of service (quality of service). In this, different nodes are involved in the information data collection and transmission to the destination nodes in the network. The different nodes are combined and presented to achieve energy-efficient data transmission and classification of the nodes. The route identification and routing are established based on the data broadcast by the network nodes. In transmitting the data packet, evaluating the data delivery ratio is necessary to achieve optimal data transmission in the network. Furthermore, energy consumption and overhead are considered essential factors for the effective data transmission rate and better data delivery rate. In this paper, a Gradient-Based Energy Optimization model (GBEOM) for the route in MANET is proposed to achieve an improved data delivery rate. Initially, the Weighted Multi-objective Cluster-based Spider Monkey Load Balancing (WMC-SMLB) technique is utilized for obtaining energy efficiency and load balancing routing. The WMC algorithm is applied to perform an efficient node clustering process from the considered mobile nodes in MANET. Load balancing efficiency is improved with a higher data delivery ratio and minimum routing overhead based on the residual energy and bandwidth estimation. Next, the Gradient Boosted Multinomial ID3 Classification algorithm is applied to improve the performance of multipath multicast routing in MANET with minimal energy consumption and higher load balancing efficiency. The proposed GBEOM exhibits ∼4% improved performance in MANET routing.     

车载Ad Hoc网络MAC协议研究

在移动自组网中,MAC协议是保证移动终端能够公平有效地共享无线信道所不可缺少的手段.近年来,随着车载通信系统的不断发展和自组网技术日益成熟,如何将二者有机结合成车载自组网已引起业界的极大关注.由于VANET自身的特点,以及其支持的业务应用种类非常丰富,现有自组网的MAC协议并不能直接用于VANET中.在简要介绍Ad Hoc网络中MAC协议的基础上,对VANET的MAC协议研究进展进行了综述,并指出了该领域的发展趋势.     

Efficient energy conservation in MANET using Energy Conserving Advanced Optimised Link State Routing model

Mobile Ad-hoc Network (MANET) is formed dynamically by the independent organisation of the mobile nodes connected through wireless links without using any centralised administration. Energy consumption is the most significant issue in the MANETs, since most of the mobile hosts operate on limited battery resources. Reduction in the energy consumption results in the increase in the lifetime and throughput of the network. The performance of existing techniques was less in terms of energy conservation issues. To overcome these limitations, this paper proposes an energy conservation mechanism integrated with a proactive MANET routing scheme. The routing schema is based on the energy level and the mobility of the nodes. Calculation of energy cost is performed based on the prediction of the energy consumption level of the node, using Energy Conserving Advanced Optimised Link State Routing (ECAO) model. The performance of the proposed ECAO model is compared with the existing Optimised Link State Routing and Advanced Optimised Link State Routing models. From the comparison result, it is clearly observed that the proposed model achieves better performance in terms of number of TC messages, Packet Delivery Ratio, average time, end-to-end delay, and link delay and energy consumption.     

移动自组网中泛播技术研究综述

对于无线移动自组网络中有限的带宽和能量资源，泛播技术可以带来更好的通信健壮性和可靠性。本文阐述了移动自组网络和泛播技术基本概念，分析和总结了移动自组网络中泛播技术在网络层，媒体访问层，应用层中的研究现状，并且讨论了泛播技术的应用背景。     

自组网中基于多信道的功率控制技术

自组网介质访问控制协议是影响自组网性能的重要因素.形式化地描述并分析了结合多信道和功率控制技术的自组网MAC协议性能特征.NS-2仿真实验表明,与没有功率控制的AODV相比较,在功率控制技术中合理的引入多信道技术,可有效的降低功率控制所引发的碰撞增加问题,增加节点和网络的生存时间.     

Power Adjusting Algorithm: A New Cross-Layer Power Saving Mechanism for Mobile Ad-Hoc Networks

Power saving is one of the key issues in Mobile Ad-Hoc Networks(MANETs).It can be realized in Medium Access Control(MAC) layer and network layer.However,previous attentions were mainly paid to MAC layer or network layer with the aim of improving the channel utilization by adopting variable-range transmission power control.In this paper we focus on the power saving in both MAC layer and network layer,and propose a Power Adjusting Algorithm(PAA).In the presence of host’s mobility,PAA is designed to conserve energy by adjusting the transmission power to maintain the route’s connectivity and restarting the route discovery periodically to find a new route with better energy efficiency dynamically.After analyzing the operations of PAA,we find that the length of route discovery restarting period is a critical argument which will affect power saving,and an energy consumption model is abstracted to find the optimal value of the restarting period by analyzing the energy consumption of this algorithm.PAA can handle the mobility of MANET by adjusting the transmission power and in the meantime save energy by restarting route discovery periodically to balance the energy consumption on route discovery and packet delivering.Simulation results show that,PAA saves nearly 40% energy compared with Dynamic Source Routing protocol when the maximum speed of mobile hosts is larger than 8m/s.     

基于能量消耗的网格路由协议

基于移动AdHoc网络环境中的节点能量消耗速度,提出一种新的网格路由协议。定义一个计算节点能量消耗速度的函数,以该函数值为路由参数,结合Floyed算法进行最优路径选择。与原有协议的比较结果表明,该协议可以降低节点能耗,延长网络生命周期。     

基于多模电台的SDMANET网络组网方法

软件定义网络（SDN）在有线网络和数据中心网络等多种网络场景中正在快速发展,然而在移动自组织网络（MANET）中SDN的使用仍然处于起步阶段。因MANET网络拓扑变化频繁、资源受限以及采用分布式组网方式等特点使得在其中应用SDN变得具有挑战性。为此,本文提出一种基于多模电台的软件定义移动自组织网络（SDMANET）组网方法。该方法使用支配集算法计算骨干节点,仅由骨干节点使用带外信道和SDN控制器通信,并在MAC层基于骨干节点进行TDMA时隙动态分配。实验结果表明,与OLSR协议和直接带外控制的SDN方法相比,本方法具有更低的网络控制开销和信道访问时延,在大规模MANET网络中性能较好。     

Managing concurrent execution of transactions in mobile ad-hoc network database systems: an energy-efficient approach

A Mobile Ad-hoc Network (MANET) is a collection of mobile, wireless and battery-powered nodes without any fixed infrastructure. Therefore, it fits well in mission-critical applications such as disaster rescue and military operations. However, when a node runs out of energy, communication may fail and transactions may be aborted if they are time-critical and miss their deadlines. In order to provide timely and correct results for multiple concurrent transactions, energy-efficient database concurrency control (CC) techniques become critical for database systems built for MANET. Due to the characteristics of MANET databases, existing CC algorithms cannot work effectively. In this paper, an energy-efficient CC algorithm is developed for mission-critical MANET databases in a clustered network architecture where nodes are divided into clusters, each of which has a cluster head, responsible for the processing of all nodes in the cluster. The cluster structure is constructed using a novel weighted clustering algorithm, which uses node mobility, remaining energy and workload to group nodes into clusters and select cluster heads. In our CC algorithm, we elect cluster heads to work as coordinating servers to conserve energy and balance energy consumption among servers, and propose an optimistic CC algorithm to offer high concurrency and avoid wasting limited system resources. Besides correctness proof and theoretical analysis, comprehensive simulation experiments were conducted, and simulation results show the superiority of our CC algorithm over existing techniques in terms of transaction abort rate, total energy consumption by all servers, and degree of balancing energy consumption among servers.     

拓扑控制对Ad Hoc网络性能的影响

研究了拓扑控制技术对MANET网络性能的影响。与其它相关文献不同的是，在分析及建立仿真模型过程中，综合考虑了拓扑控制对物理层、MAC层和网络层带来的影响，而非仅从MAC层角度出发。仿真结果说明，实施拓扑控制尽管能够带来信道空间复用能力的提高，但最终反映网络承载业务能力的网络端到端通过量指标却出现了下降。并且存在一个倾向：网络拓扑的信道空间复用能力越强。该指标越差。导致这种现象的主要原因是：在拓扑控制方案所产生网络拓扑中，分组的平均转发次数以及传输失败概率增加。