An Embedded Secondary Contention Window for In-Band Full-Duplex Enabled WLAN

In-band full-duplex wireless techniques have provided an attractive opportunity to double both spectrum efficiency and network throughput. A shared wireless channel permits two sets of directional paths, one called by primary and the other by secondary, onto which two different pair of wireless stations can send simultaneously their packets with no collision. The complexity emerges in station selection for multiple access due to random distribution, especially for WLAN. We propose in this paper an elaborate scheme to address the competition in secondary path access while keeping primary path fully compatible to the conventional 4-way handshaking of IEEE 802.11 Distributed Coordination Function (DCF). A generic framework of throughput analysis is discussed and a formulation specific to a simplified topology is deduced. Numeric evaluations show that the proposed scheme promises a maximum speedup factor beyond double in magnitude. Keywords-in-band full-duplex; WLAN; secondary path access; embedded contention window; p-consistence CSMA; throughput performance