A Fast Precoding Design Algorithm for MISO BC: An ADMM Approach

In this letter, we propose a fast precoding design algorithm to solve the weighted sum rate (WSR) maximization problem with individual rate constraints for a multiple-input single-output broadcast channel (MISO BC), by employing the convex-concave procedure (CCP) approach and the alternating direction method of multipliers (ADMM). The proposed algorithm attains the stationary point of the non-convex WSR problem and shares three salient features: only one matrix inversion, simple closed-form updates, and a parallel computational structure, particularly appealing for practical implementation. The numerical results demonstrate that our proposed algorithm achieves almost the maximum WSR but saves computing time by up to 98% compared to the state-of-the-art algorithms, revealing its practical importance.