Wireless sensor networks have been widely used for civilian and military applications, such as environmental monitoring
and vehicle tracking. In many of these applications, the researches mainly aim at building sensor network based systems
to leverage the sensed data to applications. However, the existing works seldom exploited spatial aggregation query
considering the dynamic characteristics of sensor networks.
In this paper, we investigate how to process spatial aggregation query over dynamic geosensor networks where both the
sink node and sensor nodes are mobile and propose several novel improvements on enabling techniques. The mobility of
sensors makes the existing routing protocol based on information of fixed framework or the neighborhood infeasible. We
present an improved location-based stateless implicit geographic forwarding (IGF) protocol for routing a query toward
the area specified by query window, a diameter-based window aggregation query (DWAQ) algorithm for query
propagation and data aggregation in the query window, finally considering the location changing of the sink node, we
present two schemes to forward the result to the sink node. Simulation results show that the proposed algorithms can
improve query latency and query accuracy.
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