Multiple Access Protocol for Wireless Internet Access Network with Smart Antennas

Employing smart antennas in the central access point (CAP) of wireless internet access networks is studied, and a polling based adaptive beamforming multiple access protocol (PB ABFMA) is proposed. In PB ABFMA, the CAP stimulates the corresponding mobile terminal (MT) to transmit training sequence just before the data packets transmission, so the temporal reference beamforming (TRB) can be performed by the smart antennas. The CAP schedules packet transmissions based on the polling mechanism, and a mini slot is used to keep connectivity when an MT is idle, thus, the access delay is reduced. A simple and effective collision resolution algorithm is proposed to guarantee rapid access of new arrival MTs to the channel. Based on the "request reply" traffic, the analysis of channel utilization and mean turn around delay is presented. Results show that the proposed protocol effectively supports the application of smart antennas and provide high channel utilization and low turn around delay.