Unmanned Aerial Vehicle as Data Mule for Connecting Disjoint Segments of Wireless Sensor Network with Unbalanced Traffic

This paper presents a method for federating disjoint segments of Wireless Sensor Networks (WSNs) in the presence of unbalanced traffic. The approach relies on an Unmanned Aerial Vehicle (UAV) for message ferrying. Network disconnections compromise the system operation, ergo an alternative to mitigate disconnections is important to extend the network lifetime. In our work, a UAV becomes a data mule, carrying physically packets across the disjoint partitions to assure network connection. The method presented in this article goes beyond previous work by taking into account the traffic situation among the network segments: highly communicating disjoint segments are visited more frequently than partitions with low outgoing/incoming traffic. Simulations realized evince the effectiveness of our system for concentrated traffic. In this case, a lower latency and data loss resulted when compared with the system without prioritization of highly communicating segments.