  A grid of orthogonal beams with zero column coherence can be easily
constructed to cover all prospective user equipments (UEs) in the far-field
region of a multiple-antenna base station (BS). However, when the BS is
equipped with an extremely large aperture array, the Fraunhofer distance is
huge, causing the UEs to be located in the radiative near-field region. This
calls for designing a grid of beams based on a near-field dictionary. In the
previous work, a polar-domain grid design was proposed to maintain control over
the column coherence. A limitation of this approach is identified in this
paper, and we propose an enhanced methodology for the design of a polar-domain
dictionary specifically tailored for the near-field of an extremely large
aperture uniform planar array. Through simulation results, it is demonstrated
that the proposed dictionary, employing a non-uniform distance sampling
approach, achieves lower column coherence than the benchmark and significantly
improves the localization of UEs compared to uniform distance sampling.
