A TDMA based scheduling scheme in 802.11b WLANs with access point

This paper introduces a new scheduling scheme that provides fair access to all stations in 802.11b WLANs. The scheme divides the transmission opportunities between wireless stations according to their operating conditions. Stations that face errors and can´t communicate with the access point are given more transmission time at the moment these errors reduce to compensate for their loss of service. In 802.11b wireless stations can operate at different data rates 11, 5.5, 2 and 1 Mbps. From the literature and our simulation we found that operating at lower data rates would degrade the overall performance of the system. Still, it is impractical in developing a schedule scheme to assume that a wireless station can only operate at full data rate as similar previous work. Our scheduling scheme takes in consideration that some stations may operate at data rates lower than 11 Mbps. Simulation results show that fairness between mobile stations is almost achieved.