关键词: 无线传感器网络, 查询处理, 空间范围查询, 链路质量

Abstract: In wireless sensor networks, the users often submit spatial window queries to obtain the summary information of a local area in the network such as maximum temperature, average humidity, et al. The current state-of-the-art itinerary-based spatial query processing algorithms make the assumption of the link model pertaining to the ideal disk model. However, it’s not valid in realistic networks, which leads to large energy consumption and poor quality query result. This paper proposes a link quality aware spatial window query processing algorithm called LSA(link aware spatial window query processing algorithm). It divides the query region into several grids according to the topology and link of the network, and collects data from the sensor nodes in each grid to derive the final query result. LSA traverses all the grids within the query region which ensures the query result quality of the algorithm. In order to reduce the packet loss rate of communications between nodes, a heuristic method is given which divides the query region into grids. Then, a link aware data collection algorithm is proposed to reduce energy consumption and improve the query result quality of the algorithm. Finally, this paper systematically analyzes and compares the energy consumption and the query result quality of the LSA and the existing IWQE(itinerary-based window query execution) algorithm through simulation experiments. Experimental results show that LSA algorithm outperforms IWQE in most cases.

Key words: wireless sensor network, query processing, spatial window query, link quality