Power Allocation for Rate-Splitting MISO Systems With Imperfect CSIT: A Genetic Approach.

In this paper, we propose innovative power allocation strategies for rate-splitting multiple-input single-output (MISO) broadcast channel communication systems, in the presence of imperfect channel state information at the transmitter (CSIT). First, we simplify the power allocation problem by assuming equal transmit power for private messages, leading to a closed-form expression for the power allocation for the common message. Then, we focus on the joint power allocation for common and private messages, aimed at optimizing the average sum rate. To solve the formulated non-convex problem, a genetic algorithm (GA) based method is proposed, while utilizing sample average approximation. Extensive numerical results are provided to verify the superiority of the proposed GA-based power allocation algorithm, and show its robustness to channel estimation errors and channel estimation feedback budget bits.