Semi-synchronous Channel Access for Full-Duplex Wireless Networks

Full-duplex radios are often envisioned to double wireless link capacity. Substantial work has focused on redesigning the radio hardware to achieve this theoretical gain. From a network-protocol perspective, however, it remains an open problem how to exploit full-duplex radio, and how much gain it can achieve in practical multi-cell wireless LANs. In this paper, we propose FuMAC, a channel access protocol tailored for full-duplex radios to optimally exploit their unique capabilities. FuMAC addresses a unique trade off between PHY-layer full duplex transmission and MAC-level spatial reuse, through a semi synchronous channel access principle. Its design is enabled by a novel self-interference cancellation mechanism called Active Antenna Cancellation. We verify FuMAC using software-radio implementation combined with large scale simulation. The results demonstrate that conventional MAC protocols severely underutilize full-duplex´s potential. In contrast, FuMAC can achieve more-than-doubled throughput gain over half-duplex wireless LANs and significantly outperform alternative full-duplex MAC designs, while maintaining a much higher level of fairness.