Ergodic Capacity and Placement Optimization for RSMA-Enabled UAV-Assisted Communication

This work investigates the performance of a downlink wireless network consisting of an unmanned aerial vehicle (UAV)-assisted base station (BS) that uses rate-splitting multiple access (RSMA) to serve multiple ground users (GUs) simultaneously. We analyze the network performance by deriving the closed-form expression of achievable ergodic capacity at each user. In addition to this, we maximize the ergodic capacity of the private message while guaranteeing the desired capacity of the common message. Moreover, we formulate an optimization problem to show that hovering the UAV at a certain optimal position can result in maximizing the sum capacity of the network. Monte-Carlo simulations are used to verify the accuracy of derived analytical expressions.