Antenna arrays for RSS based indoor localization systems

Abstract

In current state-of-the-art received signal strength-based localization systems a single omnidirectional antenna is often used on the receiver nodes in the wireless network. Using receiver nodes equipped with these antennas will result in received signal strength distributions with little spatial variation. Since there are less unique data points, there will be ambiguity present in the location estimate. We therefore wish to increase the diversity in the received signal strength value distribution throughout the environment by employing an antenna array. This will result in received signal strength distributions containing less ambiguities in the location estimate. Using a methodology based on mutual information, the proposed localization system using antenna arrays in the fixed receiver nodes of the network and a probabilistic radio frequency pattern matching algorithm is evaluated. This evaluation shows that the amount of ambiguities in the location estimates is reduced compared to the same localization system using omnidirectional antennas in the fixed receiver nodes.