WSN-MEs数据收集关键问题研究

发布时间：2018-04-25 20:10

本文选题：无线传感器网络 + 移动数据收集器　；参考：《苏州大学》2014年博士论文

【摘要】：无线传感器网络（WSNs）已经成为覆盖大范围应用的一项吸引人的技术。多数传统的WSN体系结构由稠密部署于传感区域的静态节点组成，节点通过单跳或多跳通信将采集到的数据传输给基站。近年来，通过在传统的WSNs中引入移动元素MEs（mobile elements）来提高网络的效率成为人们研究的热点。相比传统静态WSNs，带有移动元素的无线传感器网络（WSN-MEs）显著提高了网络的能量效率，有效降低了组网成本。然而移动性管理带来了静态WSNs所没有的诸多挑战。对WSN-MEs数据收集应用，依据不同的场景可以采用不同的模式：对实时性要求高的事件监测类应用，如何捕获移动元素轨迹构建多跳动态路由是一个挑战；对采用直接接触方式进行数据收集的应用，由于移动节点的低速会引起较大的数据收集时延。据观察，数据收集时延可以通过局部数据汇聚得到有效缩减，该类方法通常联合考虑移动性控制和路由。由于传感节点受到制作工艺、部署方式和工作环境等因素的制约，节点很容易发生故障。故障节点的存在为数据收集工作带来了很多不利影响，如收集信息的不精确、能量效率低下、数据路由不可靠等。因而，如何从数目众多的节点中识别出故障节点并且构建容错的路由机制，进而保证网络的可靠性引起了研究者越来越多的重视。本文在深入分析现有研究成果的基础上，围绕WSN-MEs中数据收集这一核心问题，展开三个方面问题的研究，主要工作包括： 1.针对高效容错的动态路由构建，给出了一种基于格的实时数据收集协议：（1）提出一个基于功率控制的弹性的和均匀的格划分模式，将网络拓扑划分为二维虚拟格结构，以此达到良好的网络扩展性和减少通信时的数据传输跳数。（2）提出了一种成员节点竞争格头的选举机制，将网络分成层次结构。该机制考虑节点的剩余能量，很好地平衡了网络节点的能量消耗，，从而可以有效延长网络寿命。（3）给出了一个初始最优数据收集树的分布式构建方法。为了降低数据传输时延，消息仅在格头组成的高层骨干网中传播，有助于降低消息复杂度。（4）理论分析和仿真结论证明了本方法的有效性，即在不同的参数设定下，协议均可以达到较好的效果。 2.针对移动元素的路线规划问题，给出了中继跳约束下基于集结模式的数据收集算法：（1）定义了在中继跳数约束下基于集结点RN（rendezvous node）的移动数据收集问题MDC-RN（mobile data collection based on rendezvous nodes），该问题联合考虑移动节点的巡行和汇聚树中的数据路由，并证明了该问题是NP难的。（2）针对定义的MDC-RN问题，我们给出了两个高效的基于集结模式的数据收集算法加以解决。第一个是从当前节点d跳邻居中优先选择具有最大负载节点作为RN候选的启发式算法；第二个算法针对WSNs特征，以分布式迭代确定RN，然后基于确定的RN，使用解决旅行售货商问题TSP（traveling salesman problem）的相关算法产生移动节点的巡行。移动节点沿该巡行周期性地访问这些RN，并通过单跳或有限跳收集其上缓存的数据。（3）理论分析和仿真实验验证了所提出算法的有效性。 3.针对数据收集的可靠性问题，给出了基于比较模型的节点故障诊断和容错路由机制：（1）探索将比较模型用于WSNs节点的故障诊断，基于故障诊断的RN选举消除了故障节点充当RN的可能性，减少了能量的消耗和故障信息的传播。（2）基于有向无环图DAG（directed acyclic graph）构建的多路路由机制，增加了系统的容错性。（3）RN选择和多跳路由机制分别考虑节点的剩余能量和传输代价，二者交替执行构成基于“轮”的协议，平衡了网络中节点的能量消耗，提高了网络的能量效率。（4）仿真实验显示，所提出的协议在通信开销、诊断延迟和能量效率等方面与类似协议相比均具有一定的优势。
[Abstract]:Wireless sensor network (WSNs) has become an attractive technology covering large range of applications. Most traditional WSN architectures are composed of static nodes densely deployed in the sensing area, and nodes transmit the collected data to the base station through single hop or multi hop communication. In recent years, the mobile element MEs (MO) is introduced into the traditional WSNs. Bile elements to improve the efficiency of the network has become a hot spot of research. Compared with traditional static WSNs, wireless sensor networks with mobile elements (WSN-MEs) significantly improve the energy efficiency of the network and effectively reduce the cost of networking. However, mobility management brings many challenges to static WSNs. For WSN-MEs data collection and application, According to different scenarios, different patterns can be used: for the application of high real-time event monitoring class, it is a challenge to capture mobile element trajectory and build multi hop dynamic routing. The application of data collection using direct contact mode will cause large data collection delay due to the low speed of mobile node. Data collection delay can be effectively reduced through local data convergence. This kind of method usually considers mobility control and routing. Because sensing nodes are restricted by factors such as manufacturing technology, deployment mode and working environment, nodes are easy to fail. The existence of fault nodes brings a lot of adverse effects on data collection work. Such as inaccuracy of collecting information, low energy efficiency and unreliable data routing, how to identify fault nodes from a large number of nodes and build fault-tolerant routing mechanism, thus ensuring the reliability of the network, has caused more and more attention to the researchers.
On the basis of in-depth analysis of the existing research results, this paper focuses on the core issue of data collection in WSN-MEs and launches three aspects of research. The main work includes:
1. aiming at the dynamic routing construction of efficient fault-tolerant, a real-time data collection protocol based on lattice is given. (1) a flexible and uniform grid partition mode based on power control is proposed, and the network topology is divided into two dimensional virtual lattice structure to achieve good network scalability and reduce the number of data transmissions during communication. (2) An election mechanism of the competitive grid head of a member node is presented, which divides the network into a hierarchical structure. The mechanism considers the residual energy of the node, balances the energy consumption of the network nodes, and can effectively prolong the network lifetime. (3) a distributed construction method for the initial optimal data collection tree is given. The message is propagated only in the high level backbone of the lattice head, which helps to reduce the complexity of the message. (4) theoretical analysis and simulation results prove the effectiveness of this method, that is, the protocol can achieve better results under different parameters.
2. for the routing problem of mobile elements, a data collection algorithm based on aggregation mode is given under the relay hop constraint. (1) the mobile data collection problem MDC-RN (mobile data collection based on rendezvous nodes) under the relay hop count constraint RN (mobile data collection based on rendezvous nodes) is defined. The problem is combined to consider the mobile node. The cruising and data routing in the aggregation tree prove that the problem is NP difficult. (2) for the defined MDC-RN problem, we give two efficient data collection algorithms based on the aggregation mode. The first is to select the heuristic algorithm with the largest load node as the RN candidate from the current node D hop neighbor; The second algorithm identifies RN with a distributed iteration for the WSNs feature, and then based on the determined RN, uses a related algorithm to solve the traveling salesman problem TSP (traveling salesman problem). The mobile node visits the RN periodically along the patrol and collects the data cached by a single hop or a finite jump. (3) Theoretical analysis and simulation experiments verify the effectiveness of the proposed algorithm.
3. in view of the reliability problem of data collection, the node fault diagnosis and fault-tolerant routing mechanism based on comparison model are given: (1) the comparison model is used to diagnose the fault of WSNs nodes, and the RN election based on fault diagnosis eliminates the possibility that the fault node acts as the RN, reduces the energy consumption and the propagation of fault information. (2) based on the The multipath routing mechanism constructed by the acyclic graph DAG (directed acyclic graph) increases the fault tolerance of the system. (3) the RN selection and the multi hop routing mechanism consider the residual energy and transmission cost of the nodes respectively. The two ones are implemented alternately to form a "wheel" protocol, which balances the energy consumption of nodes in the network and improves the energy efficiency of the network. (4) Simulation results show that the proposed protocol has some advantages over similar protocols in terms of communication overhead, delay in diagnosis and energy efficiency.

【学位授予单位】：苏州大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN929.5;TP212.9

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