The existing methods for Reconfigurable Intelligent Surface (RIS) beamforming in wireless communication are typically limited to uniform phase quantization. However, in real world applications, the phase and bit resolution of RIS units are often non-uniform due to practical requirements and engineering challenges. To fill this research gap, we formulate an optimization problem for discrete non-uniform phase configuration in RIS assisted multiple-input single-output (MISO) communications. Subsequently, a partition-and-traversal (PAT) algorithm is proposed to solve that, achieving the global optimal solution. The efficacy and superiority of the PAT algorithm are validated through numerical simulations, and the impact of non-uniform phase quantization on system performance is analyzed.

翻译：现有无线通信中可重构智能表面（RIS）波束赋形方法通常局限于均匀相位量化。然而在实际应用中，受实际需求和工程挑战影响，RIS单元相位与比特分辨率往往呈现非均匀特性。为填补这一研究空白，本文构建了RIS辅助多输入单输出（MISO）通信系统中离散非均匀相位配置的优化问题，进而提出一种分区遍历（PAT）算法以求解该问题，实现全局最优解。通过数值仿真验证了PAT算法的有效性与优越性，并分析了非均匀相位量化对系统性能的影响。