Mobility increases the surface coverage of distributed sensor networks

Coverage is a fundamental issue in sensor networks, which usually dictates the overall network performance. Previous studies on coverage issues mainly focused on sensor networks deployed on a 2D plane or in 3D space. However, in many real world applications, the target fields can be complex 3D surfaces where the existing coverage analysis methodology cannot be applied. This paper investigates the coverage of mobile sensor networks deployed over convex 3D surfaces. This setting is highly challenging because this dynamic type of coverage depends on not only sensors’ movement but also the characteristics of the target field. Specifically, we have made three major contributions. First, we generalize the previous analysis of coverage in the 2D plane case. Second, we derive the coverage characterization for the sphere case. Finally, we consider the general convex 3D surface case and derive the coverage ratio as a function of sensor mobility, sensor density and surface features. Our work timely fills the blank of coverage characterization for sensor networks and provides insights into the essence of the coverage hole problem. Numerical simulation and real-world evaluation verify our theoretical results. The results can serve as basic guidelines for mobile sensor network deployment in applications concerning complex sensing fields.