An energy-balanced swept-coverage mechanism for mobile WSNs

Coverage is one of the most important issues in Wireless Sensor Networks (WSNs). In literature, many coverage mechanisms have been proposed and employed mobile sensors to cover (heal) the coverage holes in the monitoring region. Consider that there are no redundant mobile sensors in a monitoring region. Some studies presented hole-movement mechanisms which used a mobile sensor to move a hole from one location to another, achieving the swept coverage of the monitoring region. However, in these studies, there are only some mobile sensors that participate in the hole-movement task, leading to an energy-unbalanced WSN. This paper considers a mobile WSN that contains holes and has no redundant mobile sensors to reach the spatial full coverage of the given monitoring region. To meet the swept coverage of the given monitoring region and balance the energies of mobile sensors, a distributed energy-balanced hole-movement mechanism, called EBHMM, is proposed. Theoretical analysis and performance evaluation reveal that the proposed EBHMM has better performance than existing hole-movement mechanisms in terms of the network lifetime and energy-balanced degree of mobile sensors.