Considering a two-user multi-antenna Broadcast Channel, this letter shows that linearly precoded Rate-Splitting (RS) with Successive Interference Cancellation (SIC) receivers is a flexible framework for non-orthogonal transmission that generalizes, and subsumes as special cases, four seemingly different strategies, namely Space Division Multiple Access (SDMA) based on linear precoding, Orthogonal Multiple Access (OMA), Non-Orthogonal Multiple Access (NOMA) based on linearly precoded superposition coding with SIC, and physical-layer multicasting. This letter studies the sum-rate and shows analytically how RS unifies, outperforms, and specializes to SDMA, OMA, NOMA, and multicasting as a function of the disparity of the channel strengths and the angle between the user channel directions.

中文翻译：

---

速率拆分统一 MISO 广播信道中的 SDMA、OMA、NOMA 和多播：一个简单的双用户速率分析

考虑到一个双用户多天线广播信道，这封信表明具有连续干扰消除 (SIC) 接收器的线性预编码速率分割 (RS) 是一个灵活的非正交传输框架，它概括并归入特殊情况，四个看似不同的策略，即基于线性预编码的空分多址 (SDMA)、正交多址 (OMA)、基于 SIC 的线性预编码叠加编码的非正交多址 (NOMA) 和物理层多播。这封信研究了和速率，并分析了 RS 如何统一、优于和专门用于 SDMA、OMA、NOMA 和多播，作为信道强度差异和用户信道方向之间角度的函数。