# Optimization of RIS-Assisted 6G NTN Architectures for High-Mobility UAV Communication Scenarios
## 2 Related Work
\begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Category** & **Citations** & **Key Contributions** & **Limitations/Challenges** & **How Our Work Differs** \\ \hline Intelligent Signal Processing & [PERSON] et al. [16] & AI-based adaptive phase-shift configuration. ML techniques for RIS reconfiguration. & Focus primarily on terrestrial or quasi-static channels. Limited exploration of dynamic NTN scenarios. & Proposes a joint optimization framework for RIS phase shifts in high-mobility NTN environments. & Proposes a joint optimization framework for RIS phase shifts in high-mobility NTN environments. \\ \hline \hline \multirow{4}{*}{Integration of NTNs 6G Architectures} & [PERSON] et al. [20] & System-level integration of terrestrial and non-terrestrial networks. & Limited emphasis on the interaction between RIS deployment and NTN performance under high-mobility conditions. & Provides a comprehensive simulation-based performance analysis \\  & [PERSON] et al. [21] & & & \\ \cline{1-1}  & [PERSON] et al. [23] & Spectrum sharing frameworks and massive MIMO techniques. & & \\ \cline{1-1}  & & & & \\ \cline{1-1}  & & & & \\ \hline \hline \multirow{4}{*}{Mobility Management} & [PERSON] et al. [22] & Advanced handover algorithms. Path selection techniques for NTN and LEO satellite networks. & Handover strategies are generally developed independently of RIS reconfiguration. Limited integration of physical-layer optimization. & Integrates real-time RIS reconfiguration with mobility management. Enhances handover performance while maintaining optimal signal quality in rapidly changing environments. & Simultaneously optimizes multiple performance metrics (SINR, throughput, energy efficiency, outage probability, latency). Addresses critical trade-offs for secure and efficient NTN operation in high-mobility scenarios. \\ \cline{1-1}  & & & & \\ \cline{1-1}  & & & & \\ \cline{1-1}  & & & & \\ \cline{1-1}  & & & & \\ \cline{1-1}  & & & & \\ \cline{1-1}  & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Comparison of related works with our contributions. _Distinct Contributions and Novelty of This Work_  
While prior research has predominantly focused on RIS applications in static or terrestrial environments, this paper addresses the joint optimization of RIS phase-shift configuration and UAV mobility coordination for high-mobility 6G NTNs. Departing from studies limited to individual performance metrics or simplified channel assumptions, we propose a Doppler-resilient real-time optimization framework integrating the following:  
1. A predictive RIS reconfiguration algorithm leveraging user trajectory forecasting and Doppler shift compensation;
2. Joint multi-objective optimization of SINR, throughput, outage probability, energy efficiency (EE), and latency within a unified formulation;
3. Comprehensive scenario-driven validation across urban, rural, emergency, highway, and indoor environments. Extensive evaluations reveal critical performance trade-offs neglected in prior work and demonstrate significant improvements in weighted key performance indicator (KPI) satisfaction versus state-of-the-art baselines. This integrated solution establishes a scalable foundation for RIS-enhanced 6G NTN deployments under dynamic mobility constraints.