Performance analysis of smart antenna systems for indoor wireless LANs

Given the potential market for wireless LAN (WLAN) technology, capacity within the available 2 and 5GHz frequency bands is likely to fall short of market demands. Multiple-sector antenna arrays are known to be able to provide capacity enhancement by means of interference reduction through spatial filtering. In this paper, the performance of an eight-element circular array acting as an access point in an indoor wireless LAN environment is analysed. Spatial-temporal channel data used within the analysis was obtained from physical measurements within numerous indoor environments using a state-of-the-art wideband vector channel sounder. Performance analysis of the array employing switched-sector and switched-beam architectures within Hiperlan/2 standard is appraised in terms of the averaged receive power and carrier-to-interference (C/I) ratios. The results demonstrate average improvements of up to 5 dB in the received power level through the use of the array. It is also shown that 22% of the time, two users per timeslot can be supported by the switch-sector system for a space division multiple access deployment scenario.