Energy and Delay Aware General Task Dependent Offloading in UAV-Aided Smart Farms

Edge computing offers a promising solution to enhance network reliability. In this study, we investigate the integration of mobile edge computing (MEC) technology and unmanned aerial vehicles (UAVs) within the context of smart agriculture. Smart agriculture relies on resource-constrained Internet of Things (IoT) devices for local environmental monitoring and data collection. These IoT devices send the collected data to UAVs for analysis. A central theme of this work is the focus on the applications generated by each UAV and the consideration of their topology to derive our optimization algorithm. To tackle these challenges, we propose harnessing the computational and power resources of UAVs and MEC at the network’s edge to offload and execute resource-intensive tasks in UAV-MEC-assisted networks. Our research focuses on the joint optimization of power allocation and task offloading in these wireless networks. Central to our investigation is the problem of minimizing the energy-time cost (ETC) for the UAVs, considering the interdependencies among tasks. To address this complex problem efficiently, we introduce graph convolutional neural networks (GCNs) and reinforcement learning (RL)-based techniques. We employ a directed acyclic graph (DAG) to model task interdependencies, with GCNs characterizing the DAG. Our approach incorporates an actor-critic method with embedding layers, trained using the compound-action actor-critic (CA2C) algorithm. Our findings reveal a significant improvement in minimizing both delay and energy consumption, with a 27% percent reduction in delay and a 45% reduction in consumed energy for executing complex, interdependent tasks.