I. Introduction
As One of the promising potential applications in the future of the sixth generation(6G) communication networks, unmanned aerial vehicle (UAV) can provide communication and computing services for ground users in disaster areas or temporary hot spots quickly by carrying base stations or servers under its inherent high mobility, high flexibility, and rapid deployment characteristics [1], while it is often impractical to deploy ground base stations in these areas. Correspondingly, UAV-assisted wireless communication has found wide use in data collection and machine learning model training [2], [3].