Wireless Sensor Networks (WSN) allow, thanks to the use of small wireless devices known as sensor nodes, the monitorization of wide and remote areas with precision and liveness unseen to the date without the intervention of a human operator. For many WSN applications it is fundamental to achieve full coverage of the terrain monitored, known as sensor field. The next major concerns are the energetic efficiency of the network, in order to increase its lifetime, and having the minimum possible number of sensor nodes, in order to reduce the network cost. The task of placing the sensor nodes while addressing these objectives is known as WSN layout problem. In this paper we address a WSN layout problem instance in which full coverage is treated as a constraint while the other two objectives are optimized using a multiobjective approach. We employ a set of multi-objective optimization algorithms for this problem where we define the energy efficiency and the number of nodes as the independent optimization objectives. Our results prove the efficiency of multi-objective metaheuristics to solve this kind of problem and encourage further research on more realistic instances and more constrained scenarios.

sensor networks, multiobjective optimization, metaheuristics