Slanting mmWave Subarrays in the Hybrid Architecture to Compensate for Directional Antenna Elements

Assuming the hybrid mmWave architecture and the 3GPP antenna model, we propose a new ULA-like array configuration called array of slanted subarrays (AoSSA) by allowing a non-zero relative angle between subarrays on a terminal. Considering 2-D (azimuth-only) beamforming, two sub-arrays per terminal and a range of base station and user equipment relative rotations, we compare the linear array of subarrays and the AoSSA under four different channel models. We find the slant angle of about 31 degrees optimizes the average spectral efficiency of the link for three of the four channel models and we explain why the result for the fourth channel model should be disregarded.