Traffic Control and Energy Harvesting in High Altitude Platforms: A Semi-Markov Process Approach

This study uses a cooperative communication approach to propose a radio frequency (RF) energy harvesting (EH) policy for relay nodes in space-air-ground networks. The proposed policy is employed in three-layer networks: low Earth orbit (LEO) satellites, high-altitude platforms (HAP), and user devices on the ground. This type of aerial communication network is adopted in most Internet of Things (IoT) networks. The analysis is carried out by constructing traffic and energy harvesting models. The traffic model is analyzed using the semi-Markov process due to the non-exponential behavior of some state transitions. A discrete-time Markov chain (DTMC) is used to analyze the energy harvesting model. The novel traffic model investigates the network’s practical lifetime, the average delay of source/relay packets, and throughput. The energy harvesting model is used to compute the average harvested energy of the HAP in closed form. Finally, through numerical illustrations, the impact on performance measures is shown by conducting a sensitivity analysis.