Dynamic sub-array HBF algorithm based on alternative least squares for ELAA MU-MIMO

Joint hybrid beamforming (HBF) and dynamic physical antenna port mapping algorithm based on alternative least squares (ALS) method with antenna sorting routine was proposed. It was shown that antenna subset reconfiguration provides better approximation of fully digital (FD) precoder in comparison with fixed sub-array structure in multi-user MIMO regimes significantly improving spectral efficiency. Hybrid antenna array gain improvement in a limited scanning area of arbitrary shape was also demonstrated. Proposed iterative algorithm convergence was carefully analyzed and it demonstrated fast and robust behavior. Simulation results for MU spectral efficiency were evaluated for realistic CDL-based channel model.