  We consider a wireless sensor network consists of cooperative nodes, each of
them keep adapting to streaming data to perform a least-mean-squares
estimation, and also maintain information exchange among neighboring nodes in
order to improve performance. For the sake of reducing communication overhead,
prolonging batter life while preserving the benefits of diffusion cooperation,
we propose an energy-efficient diffusion strategy that adopts an event-based
communication mechanism, which allow nodes to cooperate with neighbors only
when necessary. We also study the performance of the proposed algorithm, and
show that its network mean error and MSD are bounded in steady state. Numerical
results demonstrate that the proposed method can effectively reduce the network
energy consumption without sacrificing steady-state network MSD performance
significantly.
