Contents I. Introduction
Recently, the mm-wave 60 GHz band has brought significant consideration because it can provide much more available spectrum resource to meet the growing needs in the coming 5G, the next generation of mobile communication, for a better quality of experience (QoE) [1]. However, the mm-wave signals encounter notable propagation loss, penetrating reluctance, rain impact, and atmospheric absorption. In addition, user movement cuts the beam alignment and demands continuous retraining, noticeably enhancing the beamforming responsibility [1]. This particularly exists for user rotation. The experiments confirm that a small misadjustment of 18° degrades the link budget about 17 dB in a system with a 7° radiation pattern beamwidth. Based on IEEE 802.11ad coding sensitivities [1], the highest throughput would decrease by up to 6 Gb/s upon this degradation or cut the connection completely.
