The Impact of Using Multiple Antennas on Wireless Localization

We show that signal strength variability can be reduced by employing multiple low-cost antennas at fixed locations. We further explore the impact of this reduction on wireless localization by analyzing a representative set of algorithms ranging from fingerprint matching, to statistical maximum likelihood estimation, and to multilateration. We provide experimental evaluation using an indoor wireless testbed of the localization performance under multiple antennas. We found that in nearly all cases the performance of localization algorithms improved when using multiple antennas. Specifically, the median and the 90th percentile error can be reduced up to 70%. Additionally, we found that multiple antennas improve the localization stability significantly, up to 100% improvement, when there are small scale 3-dimensional movements of a mobile device around a given location.