# Maximization of Average Achievable Rate for NOMA-UAV Dual-User Communication System Assisted by RIS
## 7 Conclusions  
This paper investigates the RIS-assisted NOMA-UAV communication system. To maximize the average achievable rate, we break down the optimization into three sub-problems: optimizing the UAV trajectory, configuring the RIS phase shifts, and allocating power among users. The outcomes generated by the simulation indicate the proficiency of the presented optimization algorithm. Reasonable increase of RIS array elements and maximum transmission power can achieve better optimization results. This paper analyzes the NOMA-UAV communication system with RIS assistance. However, during the optimization process, we assume ideal conditions by neglecting interference and noise, which could cause deviations in practical applications. Furthermore, the computational complexity of the system model may increase in large-scale user or multi-UAV scenarios. Future research should explore more realistic channel models or focus on reducing algorithmic complexity to improve practical applicability. Conceptualization, [PERSON] and [PERSON]; methodology, [PERSON]; software, [PERSON]; validation, [PERSON] and [PERSON]; formal analysis, [PERSON]; writing--original draft preparation, [PERSON]; writing--review and editing, [PERSON] and [PERSON]; visualization, [PERSON]; supervision, [PERSON]; project administration, [PERSON]; funding acquisition, [PERSON] All authors have read and agreed to the published version of the manuscript. Figure 5: Power allocation of \(P_{1}\) with different number of RIS array elements \(M\). Figure 6: Power allocation of \(P_{2}\) with different number of RIS array elements \(M\). **Funding:** This work was supported in part by Guangxi Science and Technology Base and Talent Special Project: Research and Application of Key Technologies for Precise Navigation (Gui Ke AD25069103), and in part by the GUAT Special Research Project on the Strategic Development of Distinctive Interdisciplinary Field under Grant TS2024211. **Data Availability Statement:** Data are contained within the article. **Conflicts of Interest:** The authors declare no conflicts of interest. * [PERSON] et al. (2019) [PERSON]; [PERSON]; [PERSON] Cellular-Enabled UAV Communication: A Connectivity-Constrained Trajectory Optimization Perspective. _IEEE Trans. Commun._**2019**, _67_, 2580-2604. [CrossRef]
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