Capacity Improvement of Wireless LAN VoIP using Distributed Transmission Scheduling

This paper proposes a medium access control (MAC) protocol that provides quality of service (QoS) in voice over IP (VoIP) over Wireless Local Area Networks (WLANs). Our proposed protocol minimizes packet collision and improves voice communication quality in both single-cell and multiple-cell cases. Introduction of the proposed protocol requires only VoIP STA software modification, i.e. replacement of Access Points (APs) is not necessary. Our protocol also keeps backward compatibility with the legacy devices that do not implement the proposed method. We evaluate the performance of the proposed protocol and show that it can increase the number of accommodated VoIP calls by approximately 50%.

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