Dynamic Indexing System for Spatio-temporal Queries in Wireless Sensor Networks

Wireless sensor networks (WSN) have emerged as a powerful paradigm for real-time monitoring of physical phenomena. Depending on WSN application, indexing of sensed data is an important issue that deals with in-network organizing of the data and subsequently answering queries, with minimum power consumption. Several approaches have been developed to build data indexing systems in sensor networks. However, most of these systems are suitable to specific types of spatial or temporal queries, and entail significant communication overhead, thus creating unbalanced loads and affecting network lifetime. In this paper we present a novel data indexing system that is based on multiple hierarchical channels of data and physical space abstraction, and is capable of answering spatio-temporal queries. The proposed system also allows approximate queries to be answered quickly and efficiently.