Group-based centralized radio resource management strategies in wireless local area networks

To improve the transmission performance of wireless local area networks (WLANs), this paper proposes a distributed coordination function-based (DCF-based) medium access control (MAC) protocol that enables centralized radio resource management (RRM). In the protocol, AP and associated stations form a cooperative group, and the central controller acts as a master to organize the access of associated stations. Once the cooperative group reserves the radio resource in a traditional DCF-manner, the central controller allocates the reserved radio resources to the stations by an orthogonal frequency division multiple access (OFDMA) scheme. Since the central controller dynamically allocates the fine-grained resource blocks (RBs) to the stations through the opportunistic two-dimensional scheduling based on the channel and traffic conditions of each station, the transmission opportunities can be granted to the appropriate stations. Numerical results confirm that the proposed protocol enhance the throughput while satisfying QoS requirements.