Global navigation is supported by satellite systems. Because they may not be sufficiently reliable and precise in certain situations, terrestrial radio localization technology becomes increasingly important. It offers precise positioning of nodes equipped with radio emitters that can be constructed ad-hoc. Furthermore, transmitted radio signals like WiFi or cellular signals, can be opportunistically exploited to determine the position of the source nodes.

A typical approach uses a number of base stations (anchors) at known positions and determines the position of the nodes via ranging measurements and trilateration. Another approach is based on the angle-of-arrival (AoA) estimation which co-locates the receiving antennas to form a 2D or 3D antenna array.

“There are a number of applications of localization via AoA measurement that we are investigating: accurate positioning in indoor environments challenged by the severe multipath propagation for instance for the navigation of AGVs in warehouses, locating cars in safety critical situations, precise navigation of UAVs, tracking goods and assets,” Andrea Tonello says and adds, “We are interested in evaluating the performance limits introduced  by radio signal propagation and hardware impairments. For this, we have built hardware prototypes to test the technology.”