An SDMA algorithm for high-speed WLAN. Performance and complexity

Wireless LANs (WLANs) still offer low capacity compared to conventional wired LANs. To increase the capacity of a bandwidth-limited wireless system, its spatial efficiency can be improved. Pico-cellular WLAN architectures have been proposed to this aim. However, we showed in a previous study that pico-cellularisation has serious disadvantages. Instead, space division multiple access (SDMA) enables spatial selectivity within one cell. We present a blind SDMA algorithm suitable for a 100 Mbps WLAN. Its design is based on rigorous indoor channel modeling and is targeted towards implementation. The performance of the proposed algorithm in typical office environments is assessed using a semi-analytic simulation approach. Furthermore, the complexity required for a hardware realization is determined. We conclude that a frequency re-use factor of four is achieved by a four antenna receiver using 2000 snapshots for channel estimation