A Novel Collision Analysis For Multiple-Subcarrier Frequency-Domain Contention

Frequency-domain contention is a promising technique that can significantly improve channel utilization. Recently, a novel multi-subcarrier frequency-domain contention protocol called WiFi-BA has been proposed to solve the collision issue between data transmissions in single-subcarrier frequency-domain contention protocols. In this paper, however, we reveal that WiFi-BA has serious design defects, which will cause a new type of collision between data transmission and contention signal. We then analyze the root cause leading to such a collision and provide solutions to fix it.