本研究论文探讨了速率分裂多址 (RSMA) 在绿色通信网络中的应用，重点在于提升能源效率 (EE) 和降低发射机功耗。文章首先概述了绿色通信中RSMA的最新进展，随后提出了两种创新的鲁棒波束成形设计算法，用于在不完美信道状态信息 (CSIT) 下优化遍历能源效率。作者引入了增强型逐次凸逼近 (ESCA) 算法，并在此基础上，利用最优波束成形结构开发了一种更高效的半闭合解优化算法 (ESCA-HFPI)。数值结果表明，与传统的优化工具相比，ESCA-HFPI在保持相近性能的同时，显著降低了计算复杂度。此外，该研究首次全面比较了不完美CSIT下RSMA与其他多址技术（如空分多址 (SDMA) 和非正交多址 (NOMA)）的遍历能源效率，突显了RSMA卓越的干扰管理能力及其在绿色通信中的潜力。

Rate-Splitting Multiple Access for Green Communications: A Survey and Robust Beamforming Design

Abstract:

Rate-splitting multiple access (RSMA) is gaining increasing recognition as a pivotal technology for advancing green communication networks, primarily due to its proficiency in boosting energy efficiency (EE) and lowering power consumption at the transmitter. In this article, we commence by offering a concise overview of the latest advancements in RSMA for green communications. Motivated by the limitations identified in existing studies, we then focus on robust beamforming design of RSMA to optimize the ergodic EE with imperfect channel state information at the transmitter (CSIT). We first introduce an enhanced successive convex approximation (ESCA) algorithm, which expands upon the traditional successive convex approximation (SCA) approach for maximizing EE with perfect CSIT and adapts it to the imperfect CSIT scenario. To further reduce the computational complexity, we develop a novel and efficient beamforming optimization algorithm to tackle the ergodic EE problem. A key feature of our proposed approach is the use of the semi-closed-form optimal beamforming structure identified for the ergodic EE problem. Subsequently, we propose a fixed-point-iteration (FPI)-based algorithm to determine the optimal Lagrange dual variables within the optimal beamforming structure. Numerical results show that both proposed algorithms achieve near-optimal solutions and the efficient semi-closed-form optimization algorithm remarkably reduces the computational complexity. Moreover, this study is the first to present an extensive numerical comparison of the ergodic EE between RSMA and other baseline multiple access techniques under imperfect CSIT. These results further highlight the superior EE gains offered by RSMA, reinforcing its potential as a key enabler for green communication networks.

Published in: IEEE Internet of Things Journal ( Volume: 12, Issue: 10, 15 May 2025)

Page(s): 14469 - 14483

Date of Publication: 17 January 2025

ISSN Information:

Electronic ISSN: 2327-4662

CD: 2372-2541

DOI: 10.1109/JIOT.2025.3526250

Publisher: IEEE

Funding Agency:

10.13039/501100001809-National Nature Science Foundation of China (Grant Number: 62201347)

Shanghai Sailing Program (Grant Number: 22YF1428400)

Research Council of Finland through 6G Flagship (Grant Number: 346208)

Project DIRECTION (Grant Number: 354901)