具有局部特性的传感网链路质量估计方法  

Network Link Quality Estimation with Local Characteristics in WSNs

作　　者：李君伟[1] 李士宁[1] 张羽[1] 

机构地区：[1]西北工业大学计算机学院,西安710072

出　　处：《计算机科学》2015年第12期195-200,206,共7页Computer Science

基　　金：国家科技重大专项(2012ZX03005007)资助

摘　　要：重编程是实现无线传感器网络中软件更新的重要手段。传统的重编程协议性能评价方法仍然存在通过实验床和仿真平台评价其性能的优劣。目前,通过对重编程协议的软件更新过程建模并建立分析模型的性能评价方法,相对于传统的实验床和仿真平台,既能准确灵活地评价大规模部署的网络的性能,又能快速高效地给出性能分析结果,是当前重编程协议性能评价方法的新领域。然而,这一分析模型依赖于传感网链路质量的估计值。当前的传感网链路质量估计方法没有考虑到软件更新过程存在的局部特性,因而网络适应性差,无法广泛使用。提出了一种具有局部特性的网络链路质量估计方法,将软件更新过程中任一节点的局部邻居区域的链路质量期望作为这一节点的局部链路质量,能够更准确地反映软件更新过程的网络特征。使用这一具有局部特性的网络链路质量估计方法计算的估计值,将使得分析模型所计算出的重编程性能指标即完成时间与实验床运行时间的吻合度提高。将这一估计方法应用于分析模型,对线型和网格型网络的分析结果显示,分析结果与实验床的运行结果的误差低于5%。因此,与现有的估计方法相比,提出的方法在线型和网格型网络中适用性更强。Reprogramming （i. e. code dissemination） is one of the key technologies to enable software update in wireless sensor networks. Traditional code dissemination protocols are evaluated for performance comparisons by simulations and testbed experiments. Recently, the analytical model was proposed to characterize software update and evaluate performance of state-of-the-art code dissemination protocols because the analytical model is both lightweight and accurate for performance evaluation in large scale networks. However, the analytical model depends on estimation of network-wide link quality. The methods used to calculate network-wide link quality in previous analytical models ignore local characteristics in software update, thus the calculated network-wide link qualities are not scalable in different topologies of networks and are not accurate enough. By this observation, a novel method with local characteristics for estimation of network-wide link quality was proposed, which takes the averaged expectation of link qualities of neighborhood nodes from any node as local link quality for that node. Therefore, the proposed method an reflect network-wide software up- date accurately. When taking the estimated network-wide link quality of this proposed method as input for the analytical model to predict the performance of reprogramming, i. e. completion time of software update, the analytical results match that of testbed experiments with high accuracy. The prediction error of the analytical results is below 5% in linear and grid networks. Therefore, the proposed method is robust and adaptive in both linear and grid networks, compared with existing methods for estimating network-wide link quality.

关 键 词：无线传感器网络 网络链路质量 局部特性 软件更新 重编程 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]