无线传感器网络部署及其覆盖问题研究

无线传感器网络是近几年发展起来的一种新兴技术,在条件恶劣和无人坚守的环境监测和事件跟踪中显示了很大的应用价值。节点部署是无线传感器网络工作的基础,对网络的运行情况和寿命有很大的影响。部署问题涉及覆盖、连接和节约能量消耗3个方面。该文重点讨论了网络部署中的覆盖问题,综述了现有的研究成果,总结了今后的热点研究方向,为以后的研究奠定了基础。     

WSN中一种改进的节点部署方案

节点部署是无线传感器网络的基本问题之一,关系到网络的感知范围和信息传输服务质量。现有的部署算法需要额外探测和修复边界上的覆盖空洞,从而增加了网络部署的成本而且使得节点分布不均匀。针对这一问题,提出了一种改进的节点部署方案,首先进行边界部署,以保证边界上的完全覆盖和连通;然后在感应区域内生成一个新的凸多边形区域,在此新区域上再递归调用边界部署算法,直到整个感应区域被完全覆盖。理论分析和仿真实验表明,在部署节点个数和可扩展性方面均优于已有的部署方案。     

Lifetime Maximization Based on Coverage and Connectivity in Wireless Sensor Networks

We consider information retrieval in a wireless sensor network deployed to monitor a spatially correlated random field. We address optimal sensor scheduling and information routing under the performance measure of network lifetime. Both single-hop and multi-hop transmissions from sensors to an access point are considered. For both cases, we formulate the problems as integer programming based on the theories of coverage and connectivity in sensor networks. We derive upper bounds for the network lifetime that provide performance benchmarks for suboptimal solutions. Suboptimal sensor scheduling and data routing algorithms are proposed to approach the lifetime upper bounds with reduced complexity. In the proposed algorithms, we consider the impact of both the network geometry and the energy consumption in communications and relaying on the network lifetime. Simulation examples are used to demonstrate the performance of the proposed algorithms as compared to the lifetime upper bounds.     

Hybrid Artificial Bee Colony Algorithm for Improving the Coverage and Connectivity of Wireless Sensor Networks

Wireless Personal Communications - In this paper, we studied the wireless sensor network coverage and connectivity problem. Considering the artificial bee colony algorithm existed slow convergence,...     

混合无线传感网络覆盖优化的粒子群算法

为提高随机部署的传感网络覆盖性能,提出基于动态克隆粒子群的移动节点部署控制算法,用每个粒子表示所有移动节点的一种部署方案,在经典粒子群算法基础上,每次迭代结束后,粒子依据自身的覆盖性以及与群体中粒子的相似性决定其克隆数量和变异幅度,有效避免陷入早熟陷阱.通过与其他算法的对比仿真实验,表明该优化算法能更有效地提高网络覆盖性能.     

无线传感器网络中覆盖问题的研究

简要介绍了无线传感器网络体系结构、特点和应用领域.针对无线传感器网络节点覆盖问题进行了研究,提出了基于最短路径的覆盖算法,并给出了仿真结果.     

A Hybrid Trust Management Scheme for Wireless Sensor Networks

Wireless sensor network (WSN) consists of wireless small sensor nodes deployed in the terrain for continuous observation of physical or environmental conditions. The data collected from the WSN is used for making decisions. The condition for making critical decision is to assure the trustworthiness of the data generated from sensor nodes. However, the approaches for scoring the sensed data alone is not enough in WSN since there is an interdependency between node and data item. If the overall trust score of the network is based on one trust component, then the network might be misguided. In this work, we propose the hybrid approach to address the issue by assigning the trust score to data items and sensor nodes based on data quality and communication trust respectively. The proposed hybrid trust management scheme (HTMS) detects the data fault with the help of temporal and spatial correlations. The correlation metric and provenance data are used to score the sensed data. The data trust score is utilized for making decision. The communication trust and provenance data are used to evaluate the trust score of intermediate nodes and source node. If the data item is reliable enough to make critical decisions, a reward is given by means of adding trust score to the intermediate nodes and source node. A punishment is given by reducing the trust score of the source and intermediate nodes, if the data item is not reliable enough to make critical decisions. Result shows that the proposed HTMS detects the malicious, faulty, selfish node and untrustworthy data.     

Energy Proficient Hybrid Secure Scheme for Wireless Sensor Networks

Wireless Personal Communications - One way hash chain with a new key indicating the performance of the node as well to isolate malicious nodes from the network. Public key cryptography is derived...     

Coverage in Hybrid Mobile Sensor Networks

This paper considers the coverage problem for hybrid networks which comprise both static and mobile sensors. The mobile sensors in our network only have limited mobility, i.e., they can move only once over a short distance. In random static sensor networks, sensor density should increase as O(log L + k log log L) to provide k-coverage in a network with a size of L. As an alternative, an all-mobile network can provide k-coverage with a constant density of O(k), independent of network size L. We show that the maximum distance for mobile sensors is O( 1/sqrt(k) log^(4/3)(kL)). We then propose a hybrid network structure, comprising static sensors and a small fraction of O( 1/sqrt(k)) of mobile sensors. For this network structure, we prove that k-coverage is also achievable with a constant sensor density of O(k). Furthermore, for this hybrid structure, we prove that the maximum distance which any mobile sensor has to move is bounded as O(log^(3/4)L). We then propose a distributed relocation algorithm, where each mobile sensor only requires local information in order to optimally relocate itself. We verify our analysis via extensive numerical evaluations and show an implementation of the mobility algorithm on real mobile sensor platforms.     

无线可充电传感器网络中的充电桩部署

在传统的无线传感器网络中,由于自身能量存储的限制,电池供电的传感器节点缩短了整个网络的使用寿命,严重影响了网络性能。针对充电桩部署位置固定、位置不固定且不受限以及位置不固定且受限的3种情况,利用整数规划分别给出了具体的部署算法,使得整个传感器网络区域的充电效用最大化。最后利用Matlab进行仿真分析,与传统的全覆盖部署相比,使用该算法可以显著地减少所需要的充电桩数量。     

A Key Pre-distribution Scheme for Wireless Sensor Networks Using Hexagonal Deployment knowledge

To insure security for the messages sent among sensor nodes, it is important to establish keys for encryption to nodes which have had no prior direct contact with each other in wireless sensor networks. To solve the problem above, several key pre-distribution schemes have been proposed. In this paper, we present a novel key pre-distribution scheme using hexagonal deployment knowledge, in which the q-composite keys scheme has been improved. By using hexagonal division over the deploy- ment region, the probability of sharing common keys be- tween each sub-region and its neighboring sub-regions are equal, so the keys for encryption can be generated efficiently. The analytic results show that the scheme we pre-sented can achieve a higher connection probability of any two neighboring nodes than previous schemes, and net- work resilience against node capture can be substantially improved.     

Coverage and Connectivity-Based 3D Wireless Sensor Deployment Optimization

The wireless sensor network technology of Internet of Things (IoT) senses, collects and processes the data from its interconnected intelligent sensors to the base station. These sensors help the IoT to understand the environmental change and respond towards it. Thus sensor placement is a crucial device of IoT for efficient coverage and connectivity in the network. Many existing works focus on optimal sensor placement for two dimensional terrain but in various real-time applications sensors are often deployed over three-dimensional ambience. Therefore, this paper proposes a vertex coloring based sensor deployment algorithm for 3D terrain to determine the sensor requirement and its optimal spot and to obtain 100% target coverage. Further, the quality of the connectivity of sensors in the network is determined using Breadth first search algorithm. The results obtained from the proposed algorithm reveal that it provides efficient coverage and connectivity when compared with the existing methods.

     

Communication Coverage in Wireless Passive Sensor Networks

System lifetime of wireless sensor networks (WSN) is inversely proportional to the energy consumed by critically energy-constrained sensor nodes during RF transmission. In that regard, modulated backscattering (MB) is a promising design choice, in which sensor nodes send their data just by switching their antenna impedance and reflecting the incident signal coming from an RF source. Hence, wireless passive sensor networks (WPSN) designed to operate using MB do not have the lifetime constraints of conventional WSN. However, the communication performance of WPSN is directly related to the RF coverage provided over the field the passive sensor nodes are deployed. In this letter, RF communication coverage in WPSN is analytically investigated. The required number of RF sources to obtain interference-free communication connectivity with the WPSN nodes is determined and analyzed in terms of output power and the transmission frequency of RF sources, network size, RF source and WPSN node characteristics.     

Quality of Deployment in Surveillance Wireless Sensor Networks

When wireless sensors are used to keep an area under surveillance, a critical issue is the quality of the deployment from the sensing coverage viewpoint. In this paper, we propose several quality measures, which indicate if the deployment provides sufficient coverage, or whether redeployment is required or not. The terrain is modeled as a grid and the placement of the sensors is uniformly distributed. Neyman–Pearson detection is utilized to determine the effects of false-alarm and signal characteristics on the measures.     

Memetic Algorithm based Energy Efficient Wake-up Scheduling Scheme for Maximizing the Network Lifetime,Coverage and Connectivity in Three-Dimensional Wireless Sensor Networks

Wireless Personal Communications - In wireless sensor networks (WSNs), energy efficient wakeup scheduling of sensor nodes is one of an efficient approach for saving the energy consumption of the...     

Attempting to Model a Fresh Three Dimensional Coverage Scheme for Wireless Sensor Networks

Wireless Personal Communications - The coverage framework and the installation policies are straightforwardly linked to the feasible distribution of the restricted resources for the wireless sensor...     

Network Coverage in Interference Limited Wireless Sensor Networks

Wireless Personal Communications - The performance of a wireless sensor network is limited by the available bandwidth of the shared wireless channel. For the need to share the available bandwidth...     

无线传感器网络路径覆盖问题研究

目标跟踪是无线传感器网络的重要应用之一。在目标跟踪过程中,用户通常更关心目标移动路径的覆盖情况,而不是整个网络部署区域的覆盖情况。学术界对路径1覆盖的问题做了详细的研究,但是并没有给出路径k(k1)覆盖的分析。针对这一问题,该文首先将节点随机布设的2维传感器网络中目标移动路径的覆盖问题转化为1维线段覆盖问题,并通过理论分析给出任意直线路径满足k(k1)覆盖的概率下限。实验表明,在k较小时,该下限可以较好的逼近仿真结果。