AbstractThe combination of nonorthogonal multiple access (NOMA) and multiple input and multiple output (MIMO) systems is considered a promising approach for 5G mobile communication networks. In addition, techniques such as user selection and beamforming could be applied to improve some parameters of system performance. In this context, we propose a joint user selection, adaptive power allocation, and beamforming algorithm for the downlink of massive MIMO NOMA systems in order to maximize the throughput of users. To this end, we present a novel optimal beamforming solution scheme based on the adaptive computation of signal power values to maximize system throughput, considering the less interfering users. To evaluate the performance of the proposed algorithm, simulations were performed considering different power allocation algorithms.