A new antenna selection scheme for MIMO-NOMA systems with multiple-antenna users

Non-orthogonal multiple access (NOMA) is a promising technology for the next generation wireless communication networks. The benefits of this technology can be further enhanced through deployment in conjunction with multiple-input multiple-output (MIMO) systems. Antenna selection plays a critical role in MIMO-NOMA systems as it has the potential to significantly reduce the cost and complexity associated with radio frequency chains. This paper considers antenna selection for downlink MIMO-NOMA networks with multiple-antenna base-station (BS) and multiple-antenna user equipments (UEs). An iterative antenna selection scheme is developed for a two-user system, and to determine the initial power required for this selection scheme, a power estimation method is also proposed. The proposed algorithm is then extended to a general multiuser NOMA system. Numerical results demonstrate that the proposed antenna selection algorithm achieves near-optimal performance with much lower computational complexity in both two-user and multiuser scenarios.