摘要
1 Introduction The lifetime of wireless sensor networks(WSNs)is restricted by the limited energy of battery-powered sensor devices,making the lifetime extension a critical problem in real applications[1].Several aspects have been examined in previous works to extend the lifetime of WSNs,such as the deployment position,the network routing strategy and the sensing range adjustment.Given the fact that there are often many redundant sensors,a practical way to extend the lifetime of a WSN is to partition the sensors into subsets,each of which can cover all the targets[2].Then the sets are activated one by one,extending the lifetime of a WSN to times of the battery lifetime of a sensor.The problem of finding the maximal is abstracted as the set k-cover problem.
基金
This work was partially supported by the National Natural Science Foundation of China(Grant Nos.41930110,61872272 and 61640221)。