IEEE 802.11e Enhanced Distributed Channel Access (EDCA) Throughput Analysis

The upcoming standard IEEE 802.11e will provide Quality of Service (QoS) support in Wireless Local Area Network (WLAN). The contention based channel access method called Enhanced Distributed Channel Access (EDCA) is considered as the mandatory mode for Medium Access Control (MAC) in IEEE 802.11e. This paper presents an accurate throughput analytical model for EDCA in saturated situation. The analytical model is suitable for both basic access and RTS/CTS access mechanisms. It considers the features in EDCA such as different Arbitration Inter-frame Space (AIFS) and contention window for different Access Category (AC), and virtual collision for different priority queue in the same station; and can be easily extended to other features such as Transmission Opportunity (TXOP), etc. The analytical model is evaluated by extensive simulation results, and it provides deep understanding of the effect by different parameter setting to the throughput.