Adaptive Scheduling for Asymmetric Beamforming Training in IEEE 802.11ay-based Environments

IEEE 802.11ay introduced Beamforming for Asymmetric Links (BAL) in its D0.3 release. BAL aims to guarantee an efficient Beamforming Training (BT) when a distant station (STA) has insufficient link budget to communicate with the Access Point (AP) during the BT phase. BAL makes the use of directional BAL Allocation (BALA) to avoid the usage of quasi-omni pattern at the AP side, and thus to maximize the reception gain. However, the directional BALA scheduling is left up to implementers/vendors in the IEEE 802.11ay draft. In this article, we propose a novel and dynamic algorithm to schedule BALA: the Adaptive Scheduling and random BALA Backoff (AS-BB) algorithm. AS-BB uses the Signal-to-Interference-plus-Noise Ratio (SINR) to dynamically schedule directional BALAs and allows the STA to retry the BT in the remaining BALAs. Simulation results show that the AS-BB achieves better performance than the baseline 802.11ay BAL especially in terms of the BT convergence time and BAL success rate.