Capacity improvement of high density wireless LAN networks using adaptive directional antenna

This paper evaluates capacity improvement of high density wireless LAN networks using adaptive directional antenna, in terms of channel capacity and system capacity based on IEE802.11a OFDM PHY with CSMA based MAC protocol. Simulation results show that the utilization of adaptive directional antenna increases channel and system capacity and the improvement becomes large as the AP deployment density becomes scarcer. In addition, this paper compares two adaptive directional antenna control schemes, i.e. directivity tracking scheme and directivity switching scheme, and reveals that the directivity switching scheme achieves almost the equivalent channel and system capacity improvement as the directivity tracking scheme.