A Novel CQI Feedback Channel for Cellular UAV System

The utilization of Unmanned Aerial Vehicles (UAVs) is rapidly growing in a wide range of application due to their ease of deployment, low maintenance cost and high mobility. In particular, these advantages are used more effectively by the UAV when interacting with cellular networks such as 5G and beyond 5G. This system is defined as a cellular-UAV system [1]. In order to implement this system, reliable communication between base station and UAV is required. That is, well-designed CQI feedback mechanism is one of the essential technologies to be equipped. In traditional cellular network, the base station requires Channel Quality Indicator (CQI) feedback from users in order to determine a reasonable Modulation and Coding Scheme (MCS) in multicast system. However, traditional techniques also increase essential feedback as the group size increases and cause more signal overhead. This crucial problem can be equally applied to the cellular-UAV system. To cope with this problem, this paper proposes a new type of CQI feedback mechanism. The proposed schemes are expected not only to reduce signalling overhead but also to increase spectral efficiency, which is further demonstrated by the simulation results.