Energy consumption is one of the key problems on the performance of wireless sensor networks(WSN) and power control is the most efficient way to work out this problem.This paper studies the ultrawide band(UWB) based WSNs and presents a clustered global optimization power assignment model.Aimed at minimizing the network power consumption,a solving method using LP under lexicographic maxmin(LMM) strategy has been developed.Simulation results show that average power consumption and the probability of activating link access can be improved by the proposed LLM strategy.