Alocação de recursos para redes móveis empregando RSMA com múltiplas subportadoras

Abstract

This work explores a resource allocation problem for mobile networks considering a scenario with multiple subcarriers in a system employing Rate-Splitting Multiple Access (RSMA). The system model consists of a downlink composed of a base station with multiple antennas and users with a single antenna. For each available subcarrier in the system, a unique pair of users is associated, to which the RSMA mechanism is applied. For each pair of users, the directions of the private precoders are defined using Zero Forcing (ZF), and the direction of the common precoder is designed in such a way that the common rate of the pair is maximized. The studied problem aims to maximize the total user rate weighted by factors that can be configured to improve system fairness, for example. In the optimization process, it is necessary to allocate the total available power in the system between the common message and the private messages of each pair associated with the subcarriers. In this work, two low complexity solutions were proposed for the optimization problem. These solutions were compared with two benchmarks developed to demonstrate how the steps that compose the solutions improve the performance. The first benchmark solution consists of randomly matching pairs of users and subcarriers and using the power allocation algorithm proposed in the first solution. The second benchmark solution utilizes the matching of pairs of users and subcarriers used in both proposed solutions with equal power allocation.