Toward UL-DL Rate Balancing: Joint Resource Allocation and Hybrid-Mode Multiple Access for UAV-BS-Assisted Communication Systems

In this paper, we investigate unmanned aerial vehicle (UAV) assisted communication systems that require quasi-balanced data rates in uplink (UL) and downlink (DL), as well users’ heterogeneous traffic. To the best of our knowledge, is first work to explicitly joint UL-DL optimization for UAV under requirements. A hybrid-mode multiple access (HMMA) scheme proposed toward traffic, where non-orthogonal (NOMA) targets high average rate, while orthogonal (OMA) aims meet instantaneous rate demands by compensating their rates. HMMA enables a higher degree freedom achieves superior minimum among users than NOMA or OMA schemes. Under HMMA, resource allocation algorithm with closed-form optimal solution UL/DL power achieve UL DL. Furthermore, considering error propagation successive interference cancellation (SIC) NOMA, an enhanced-HMMA proposed, which demonstrates robustness against SIC scheme.