A non-uniform node deployment approach for event detection sensor networks

Due to the traversal-multicast data transmission manner of the sensor network, the energy consumption of the network is unbalanced and the nodes close to the sink will consume more energy and die faster. This leads to the energy hole problem. In order to solve this problem, many non-uniform node deployment schemes have been proposed for event detection sensor networks. All these works did not consider the impacts of the spatial and temporal distribution on the node deployment strategy. However these factors are truly important, if the energy consumptions of nodes, in active mode, without transmitting or receiving data, are taken into concern. In this paper, the effects of spatial and temporal distribution on the node deployment are considered. Firstly the data transmission amount of the network is calculated, taking the spatial distribution of the events and coverage effects into concern. Exploiting this result the energy balance equation is proposed based on the temporal density of the events, for estimating the network lifetime. Accordingly the non-uniform distribution strategy is proposed, based on the estimation of the network lifetime, to fulfil the requirements of the applications. Numerical and experimental results are further provided to show the feasibility of the presented model.