A channel reservation based multi-channel MAC protocol with serial cooperation for the next Generation WLAN

Most recently, an enhancement amendment named IEEE 802.11ax is proposed by the High-Efficiency WLAN (HEW) Task Group for the Next Generation WLAN (NGW), with a focus on improving spectrum efficiency as well as area throughput. However, collisions among stations (STAs) and Low-Rate-Links (LRLs) severely degrade the network performance, which have become a great matter of concern. In this paper, a channel reservation based multi-channel MAC protocol with serial cooperation is proposed for the next generation WLAN, called CRSC-MMAC, to explore the capabilities of both cooperative relay and channel reservation. In particular, with cooperative relay available, a LRL is divided into two wireless links that sequentially occur on the same data channel with higher data rate. Besides, by using multi-step channel reservation, multiple cooperative transmission opportunities can be reserved in advance with only one successful handshake on the control channel, and thus collisions are effectively alleviated. Extensive simulations are deployed using ns-2 simulator, simulation results show that saturation throughput of the proposed CRSC-MMAC protocol is nearly two times of that of the `Baseline' scheme, and average packet delay of CRSC-MMAC is decreased by nearly 33%.