Novel DCF-based multi-user MAC protocol and dynamic resource allocation for OFDMA WLAN systems

To enhance the throughput of wireless local area networks (WLANs) while satisfying the quality of service (QoS) requirements, this paper proposes a novel DCF-based multi-user MAC protocol employing orthogonal frequency division multiple access (OFDMA) scheme. In the proposed protocol, an access point (AP) acts as a master to organize all the stations within the basic service set (BSS) and reserves the radio resource by the conventional distributed coordination function (DCF). In the resource reservation period, the AP performs a flexible access control utilizing the fine-grained resource block and the opportunistic scheduling based on the QoS requirements and the channel condition of each station. With the objective to increase the spectrum efficiency as well as to satisfy the QoS requirements, this paper also proposes a dynamic resource allocation algorithm. Numerical results confirm that the proposed multi-user MAC protocol ensures the QoS requirement with a high probability and enhances the throughput performance.