Energy efficient real-time data aggregation in wireless sensor networks

This paper studies the energy efficient routing for data aggregation in wireless sensor networks. The data aggregation tree is a tree where the root of the tree is the data center called the sink node and the other nodes are sensor nodes. The sensor nodes sense the data and pass the data back to the data center along the data aggregation tree. We consider a real-time scenario where the data aggregation must be performed within a specified latency constraint. The objective is to minimize the overall energy cost of the sensor nodes for data aggregation subject to the latency constraint. The original contributions of the paper include: 1) Development of an analytic model for IEEE Standard 802.15.4 CSMA-CA to compute the worst case delay for a sensor node to aggregate the data from all its child nodes in the aggregation tree; 2) Proposal of a heuristic algorithm for constructing data aggregation trees that minimize total energy cost under the latency bound obtained from our analytical model. Extensive simulations have been conducted and the results verify the validity of the proposed analytical model and the superior performance of the proposed algorithm for constructing aggregation trees. Copyright 2006 ACM.