This letter introduces a novel resource allocation algorithm for achieving max-min fairness (MMF) in a rate-splitting multiple access (RSMA) empowered multi-antenna broadcast channel. Specifically, we derive the closed-form solution for the optimal allocation of the common rate among users and the power between the common and private streams for a given practical low-complexity beamforming direction design. Numerical results show that the proposed algorithm achieves at least 90% of the MMF rate obtained by the conventional iterative optimization algorithm while only takes an average of 0.1 millisecond computational time, which is three orders of magnitude lower than the conventional algorithm. It is therefore a practical resource allocation algorithm for RSMA.

翻译：本文提出了一种新颖的资源分配算法，用于在速率分裂多址接入（RSMA）赋能的多元天线广播信道中实现最大最小公平性（MMF）。具体而言，针对一种实用的低复杂度波束赋形方向设计，我们推导出了用户间公共速率以及公共流与私有流之间功率最优分配的闭式解。数值结果表明，所提算法至少能达到传统迭代优化算法所获MMF速率的90%，而其平均计算时间仅为0.1毫秒，比传统算法低三个数量级。因此，该算法是一种实用的RSMA资源分配算法。