现有无线传感器网络环境下的空间范围聚集查询处理算法没有综合考虑节点移动、节点失效和通信链路失效等因素对查询处理的影响,导致查询成功率低和能量消耗大.本文提出了利用节点冗余保证查询处理过程鲁棒性的空间范围聚集查询处理算法RSA(Robust Spatial window aggregation query processing Algorithm),它将查询区域划分为若干个网格,沿一条路线依次收集各网格内所有节点的数据.RSA算法给出了一种自适应的网格大小设置方法和基于网格面积的网格代表节点选择策略,以减少算法的能量消耗和提高查询成功率;给出了基于目标矩形的方法以绕过不存在节点的区域,从而避免查询处理过程出现中断.仿真实验结果表明,RSA算法优于现有的IWQE算法.
The current state-of-the-art spatial window aggregation query processing algorithms in wireless sensor networks do not take node movement,link failures and node failures into consideration in an integrated way, which results in low query success rate and large energy consumption. We propose a spatial window query processing algorithm called RSA which takes advantage of node redundancy to ensure the robustness of query processing. It divides the query region into several grids and collects the data of the nodes within each grid along a well-designed itinerary. An adaptive grid size setting method and a representative node selection slrategy for the grids is put forward to reduce energy consumption and increase query success rate. We propose an approach based on target rectangle to bypass the region without nodes in order to avoid interruptions in the process of query processing. Experimental results show that RSA outperforms the existing lWQE algorithm.