Network-Load Aware Adaptive Channel Access Control for WLAN

Xiaoyan Wu, Qinghe Du, Pinyi Ren

School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an, China.
School of Electronic and Information Engineering, Xi’an Jiaotong University, Xi’an, China 2National Mobile Communications Research Laboratory of Southeast University, Nanjing, China.

DOI: 10.4236/cn.2013.53B2085                

Abstract

Wireless local area network (WLAN) brings us a low cost and high bandwidth experience and thus plays a critically important role in current/future networks to support high-rate transmissions. To better provide quality-of-service (QoS) for WLAN users, we in this paper propose an improved scheme called “A-EDCA”(adaptive EDCA), based on enhanced distributed channel access (EDCA) of IEEE 802.11e under the infrastructure mode. Our proposed scheme aims at efficiently adapting the transmission over WLAN to the time-varying network conditions and mitigating the competition ability unfairness between access point (AP) and non-AP stations (STAs). Specifically, all non-AP STAs adaptive-ly modify the contention window based on the network condition. Moreover, AP skips the backoff phase by setting its backoff counter as zero when non-AP STA completes transmission successfully to relieve the unfairness. At last, simulation results demonstrate the effectiveness of the proposed approach.

Keywords

Quality of Service (QoS); IEEE 802.11e; Enhanced Distributed Channel Access (EDCA)

Conflicts of Interest

The authors declare no conflicts of interest.

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