A new architecture for hierarchical sensor networks with mobile data collectors

Abstract

Hierarchical sensor networks that use higher-powered relay nodes as cluster heads have gained popularity in recent years. An important design problem in such networks is to determine an appropriate placement scheme for the relay nodes, in order to ensure adequate coverage and connectivity requirements with as few relay nodes as possible. Current placement techniques available in the literature typically do not consider the effects of node mobility on the placement strategy. Recently, the use of mobile data collectors (MDC) have been shown to improve network performance in a variety of sensor network applications. In this paper, we have proposed a new hierarchical architecture for heterogenous sensor networks using relay nodes, with a MDC. Our goal is to use a minimum number of relay nodes and place them optimally, such that each sensor node can send its data to at least one relay node and the trajectory of the MDC visiting the relay nodes is as short as possible. We have presented an Integer Linear Program (ILP) that jointly optimizes the above objectives for such networks. We have shown that our integrated approach can lead to significant improvements compared to the case where the problems of relay node placement and determining an optimal trajectory of the MDC are considered independently. © 2010 Springer.