Approximation algorithm for distance constraint sweep coverage without predetermined base stations.

In a sweep-coverage problem, each point of interest should be visited at least once by some mobile sensor every required time interval. Because of energy constraint, each mobile sensor has to visit a base station for replenishment before running out of its power. We model the problem as a distance constraint sweep-coverage problem the goal of which is to minimize the sum of the number of mobile sensors and the number of base stations used to meet the requirements. This paper presents an approximation algorithm with a guaranteed approximation ratio 7. [ABSTRACT FROM AUTHOR]