Recently, intelligent reflecting surface (IRS)-aided millimeter-wave (mmWave) and terahertz (THz) communications are considered in the wireless community. This paper aims to design a beam-based multiple-access strategy for this new paradigm. Its key idea is to make use of multiple sub-arrays over a hybrid digital-analog array to form independent beams, each of which is steered towards the desired direction to mitigate inter-user interference and suppress unwanted signal reflection. The proposed scheme combines the advantages of both orthogonal multiple access (i.e., no inter-user interference) and non-orthogonal multiple access (i.e., full time-frequency resource use). Consequently, it can substantially boost the system capacity, as verified by Monte-Carlo simulations.

翻译：近年来，无线通信领域开始关注可重构智能表面（IRS）辅助的毫米波（mmWave）与太赫兹（THz）通信技术。本文旨在针对这一新型范式设计一种基于波束的多址接入策略。其核心思想是利用混合数模阵列中的多个子阵形成独立波束，每个波束定向对准目标方向，从而抑制用户间干扰并消除非期望信号反射。该方案融合了正交多址（即无用户间干扰）与非正交多址（即全时频资源利用）的双重优势。蒙特卡洛仿真验证表明，该方案可显著提升系统容量。