Since massive multiple-input multiple-output (MIMO) array and beamforming significantly improve spectrum efficiency, where beamforming adapts the radiation pattern of the massive array, most previous studies focus on the MIMO beamforming optimization problem to maximize the utility of the system by assuming that a massive array consists of an isotropic antenna. This research work was conducted to investigate the beamforming optimization problem with practical elements in a MIMO array. By inserting the effect of a practical antenna array gain in the channel model, the impact of array elements feeding on the beamforming optimization problem could be illustrated. Furthermore, the beamforming optimization, non-convex issue, is reformulated to synonymous convex optimization issue, through a weighted minimum mean square error (WMMSE) technique. Consequently, a conformal array (CfA) with a half wavelength dipole element is proposed at the base station (BS). The simulation results display that the suggested WMMSE-beamforming technique performance with considering antenna array gain effect can yield much better and accurate system performance than the other algorithms. Eventually, to analyze the impact of array gain on the optimization problem solution in addition to boot the network capacity, a curl antenna array in octagonal prism geometry is created. The curl antenna is circularly polarized and has a high gain compared to the half-wavelength dipole.
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