Adaptive Reservation-Assisted Collision Resolution Protocol for Wireless Local Area Networks

In conventional IEEE 802.11 medium access control protocol, the distributed coordination function is designed for the wireless stations (WSs) to perform channel contention within the wireless local area networks (WLANs). Packet collision is considered one of the major issues within this type of contention-based scheme, which can severely degrade the network performance for the WLANs. Research work has been conducted to modify the random backoff mechanism in order to alleviate the packet collision problem while the WSs are contending for channel access. However, most of the existing work can only provide limited throughput enhancement under specific number of WSs within the network. In this paper, an adaptive reservation-assisted collision resolution (ARCR) protocol is proposed to improve the packet collision from the random access schemes. With its adaptable reservation period, the contention-based channel access can be adaptively transformed into a reservation-based system while there are pending packets required to be transmitted from the WSs. Furthermore, according to the designed reservation table within the access point, the fairness for channel access between the WSs is addressed within the ARCR protocol. Numerical results indicate that the proposed ARCR scheme can outperform the existing schemes with enhanced channel utilization and network throughput.