The resolution of near-field beamforming is an important metric to measure how effectively users with different locations can be located. This letter identifies the condition under which the resolution of near-field beamforming is not perfect. This imperfect resolution means that one user's near-field beam can be still useful to other users, which motivates the application of non-orthogonal multiple access (NOMA). Both the analytical and simulation results are developed to demonstrate that those near-field beams preconfigured for legacy users can indeed be used to effectively serve additional NOMA users, which improves the overall connectivity and system throughput.

翻译：近场波束赋形的分辨率是衡量其区分不同位置用户能力的重要指标。本文揭示了近场波束赋形分辨率非理想的条件。这种非理想分辨率意味着某一用户的近场波束仍可对其他用户发挥作用，从而为非正交多址接入（NOMA）的应用提供了契机。通过分析与仿真结果，本文证明为传统用户预先配置的近场波束实际上能够有效服务于额外NOMA用户，从而提升整体连接性能与系统吞吐量。