A cloud of UAVs for the Delivery of a Sink As A Service to Terrestrial WSNs

One of the primary tasks of wireless sensor networks (WSNs) is the collection of data from a field of interest. However, in practice, maintaining a total connectivity between sensors is not always possible, and sensors may be scattered along the sensing area, forming a set of isolated cluster of nodes that are unable to deliver the collected data. In this paper, we provide a three-layer based cloud architecture, showing the use of a network of drone quadcopters for the delivery of a Sink As A Service to terrestrial mobile sensor nodes. The set of quadcopters are in charge of coordinating their movement to collect data from terrestrial cluster heads (local data collectors) and cooperate together to relay these data to the nearest base station. As the used number of terrestrial collectors (i.e., clusters heads) has a great impact on the data delivery delay and also on the energy consumption of the quadcopters, we develop an analytical model that allows determining the optimal number of terrestrial clusters of sensors. A numerical analysis is conducted to assess the variation of the optimal values of clusters' width, delivery delay, and consumer energy, with respect to the quadcopters speed, the network throughput, and the total number of sensors.