WiFi Assisted Dual-band MAC Protocol for Coordinated Beamforming among WiGig APs in Indoor Environment

摘要

Wireless Gigabit (WiGig) Access Points (APs) using 60 GHz unlicensed frequency band are considered as a key enabler for future gigabit Wireless Local Area Networks (WLANs) as well as 5 G cellular networks. Beamforming (BF) is tremendously used with WiGig transmissions to enhance the link quality and overcome the channel propagation loss. The exhaustive search BF protocol, currently used by WiGig APs, causes a lot of packet collisions when multiple APs tend to work concurrently using random access. Accordingly, system throughput is highly decreased with a high increase in packet delay and packet dropping rate. In this paper, we propose an efficient dual-band (5 GHz/60 GHz) Medium Access Control (MAC) protocol to coordinate the BF operation among the WiGig APs using their wide coverage 5 GHz (WiFi) interfaces. Therefore, concurrent WiGig data transmissions can be successfully accomplished with a low number of packet collisions. Using the proposed coordinated BF, a higher system throughput, a lower packet delay and a lower, packet dropping rate than those obtained using the conventional BF can be achieved.