Adaptive Multilink Channel Access Under Cross-Link Interference in Next-Generation WLANs

Multilink operation (MLO) has recently been proposed to provide extremely high throughput by simultaneously exploiting multiple links for next generation wireless local area networks (WLANs). To transmit and receive packets using MLO, a multilink device (MLD) should have the capability to successfully separate signals on each of the multiple links. However, if frequency separation between the two multiple links is not sufficient, the transmission of a station (STA) on an MLD causes cross-link (self) interference to other STAs on the other link on the same MLD. An STA affected by cross-link interference can not decrease its back-off counter, resulting in lower channel access probability and accordingly lower throughput compared to a legacy STA on the same link. Based on a thorough analysis, we find an appropriate contention window (CW) size of an STA on the MLD, aiming to allow it to achieve as much throughput as a legacy STA on the same link. Through extensive ns-3 simulations, we show that our proposed scheme successfully compensates for the loss of access opportunities of an STA on the MLD under cross-link interference without compromising network throughput.