title: Low-complexity user selection for rate maximization in MIMO broadcast channels with downlink beamforming.
abstract: We present in this work a low-complexity algorithm to solve the sum rate maximization problem in multiuser MIMO broadcast channels with downlink beamforming. Our approach decouples the user selection problem from the resource allocation problem and its main goal is to create a set of quasiorthogonal users. The proposed algorithm exploits physical metrics of the wireless channels that can be easily computed in such a way that a null space projection power can be approximated efficiently. Based on the derived metrics we present a mathematical model that describes the dynamics of the user selection process which renders the user selection problem into an integer linear program. Numerical results show that our approach is highly efficient to form groups of quasiorthogonal users when compared to previously proposed algorithms in the literature. Our user selection algorithm achieves a large portion of the optimum user selection sum rate (90%) for a moderate number of active users.
authors.affiliation: Department of Electronics, Telecommunications and Informatics, Aveiro University, Aveiro, Portugal ; Instituto de Telecomunicações, Campus Universitário de Santiago, P-3810-193 Aveiro, Portugal.
authors.forename: Eduardo
authors.identifier: 0000-0003-0024-2707
authors.initials: E
authors.lastname: Castañeda
authors.affiliation: Department of Electronics, Telecommunications and Informatics, Aveiro University, Aveiro, Portugal ; Instituto de Telecomunicações, Campus Universitário de Santiago, P-3810-193 Aveiro, Portugal.
authors.forename: Adão
authors.initials: A
authors.lastname: Silva
authors.affiliation: Instituto de Telecomunicações, Campus Universitário de Santiago, P-3810-193 Aveiro, Portugal.
authors.forename: Ramiro
authors.identifier: 0000-0002-1054-1818
authors.initials: R
authors.lastname: Samano-Robles
authors.affiliation: Department of Electronics, Telecommunications and Informatics, Aveiro University, Aveiro, Portugal ; Instituto de Telecomunicações, Campus Universitário de Santiago, P-3810-193 Aveiro, Portugal.
authors.forename: Atílio
authors.initials: A
authors.lastname: Gameiro
mesh_terms: D000465:Algorithms; D011845:Radio / Q000592:standards*; D011846:Radio Waves