Near-field Beamforming Technique Based on 3-D Cylindrical Array: Enlarging Region and Improving Spectral Efficiency

For large incidence/emergence angles in uniform linear arrays, the near-field region shrinks sharply. In this paper, we present Uniform 3D Cylindrical Array (UCA-3D), which can enlarge the near-field region and improve the spectral efficiency. Specifically, using the rotational symmetry of UCA-3D, we can obtain near-field regions that are uniformly enlarged at all angles. As UCA-3D can generate orthogonal near-field beams along the same direction, we can improve the spectral efficiency. The simulation results prove that the theory is valid, and the UCA-3D is feasible.