Wi-Fi azimuth and position tracking using directional received signal strength measurements

A new approach for estimating and tracking the azimuth angle regarding north and a two-dimensional position of a mobile unit is presented. Outdoors, the azimuth angle of a device can be easily detected using an electronic compass and the position can be calculated using a global navigation satellite system (GNSS). Indoors, magnetic disturbances lead to unreliable compass outputs. Also, indoors there exists no standard positioning system like GNSS outdoors. The presented approach is based on Wi-Fi signal strength measurements collected by four horizontally arranged directional antennas. To proof the concept the well known Wi-Fi fingerprinting based on the normalized Euclidean distance in signal space has been adopted. A test with measurements collected in a laboratory demonstrates the feasibility of the approach. Especially in indoor environments this facilitates the use of electronic guides that offer additional information by means of augmented reality, e.g. on museum exhibits in visual range.