无线传感网中一种低成本的信息质量感知路由协议

摘要

当无线传感器网络出现感兴趣的事件时，可能导致多个传感器被激活，出现数据爆炸和冗余。数据融合技术利用传感器数据间的时空相关性，降低了流量负载和数据拥塞，然而这会降低融合中心收集数据的信息质量（IQ）。鉴于此，对给定信息质量（IQ）约束条件下，如何寻找成本最低的路由树问题展开研究。该问题属于 NP 难解的 Steiner 树问题，提出一种 IQ 感知路由协议。该协议构建一个可以跨越无线传感器网络所有传感器的基于距离的初始融合树，当数据包到达融合中心时，它将利用贪婪近似算法修剪原先的融合树，进而保证：（1）生成的融合树的累积 IQ 满足给定的 IQ 约束；（2）修剪过后融合树上被激活节点收集数据的成本最低。仿真实验结果表明，该方案在提高数据融合质量和降低通信成本方面的性能都要优于已有的方案。%Upon the occurrence of a phenomenon of interest in a wireless sensor network,multiple sensors may be activated,which leads to data implosion and redundancy.Data fusion techniques exploit spatiotemporal correlation among sensory data and reduce traffic load as well as mitigate data congestion.However,this is often at the expense of loss in information quality (IQ)of data that is collected at the fusion centre.In this work,we address the problem of finding the least-cost routing tree that satisfies a given IQ constraint,which is a variation of the classical NP-hard Steiner tree problem in graphs.We propose an IQ-aware routing (IQAR)protocol,which constructs a distance-based initial aggregation tree that spans all the sensors in WSN,when the data packets reach the fusion centre,it utilises a greedy similarity algorithm to prune the original aggregation tree and thereby ensures:(i)the aggregated IQ of generated aggregation tree satisfies a given IQ constraint;and (ii)the total cost of collecting data by the activated nodes in pruned aggregation tree is minimised.Simulation experimental results show that the performance of the proposed scheme is better than existing schemes in terms of improving data fusion quality and reducing communication cost.