An Efficient HCF Scheduling Mechanism in Mixed Traffic Scenarios

In this paper an efficient scheduling mechanism for wireless local area networks (WLAN) is proposed. This innovative scheme, named hybrid HCCA-EDCA centralised scheme (HHE-CS), is based on the hybrid coordination function (HCF) protocol introduced by the IEEE 802.11e standard. The HHE-CS aims at satisfying the user quality of service (QoS) demands for real time (RT) services with variable bit rate while maximising the throughput of best effort users. This paper proves conclusively that an adequate allocation of downlink and uplink traffic between EDCA and HCCA increases system performance as compared with more traditional schemes in which all best effort traffic is exclusively delivered by a distributed mechanism like EDCA.