Combination of UWB and GPS for indoor-outdoor vehicle localization

GPS receivers are satellite-based devices widely used for vehicle localization that, given their limitations, are not suitable for performing within indoor or dense urban environments. On the other hand ultra-wide band (UWB), a technology used for efficient wireless communication, has recently being used for vehicle localization in indoor environments with promising results. This paper focuses on the combination of both technologies for accurate positioning of vehicles in a mixed scenario (both indoor and outdoor situations), which is typical in some industrial applications. Our approach is based on combining sensor information in a Monte Carlo localization algorithm (also known as particle Filter), which has revealed its suitability for probabilistically coping with a variety of sensory data. The performance of our approach has been satisfactorily tested on a real robot, endowed with a UWB master antenna and a GPS receiver, within an indoor-outdoor scenario where three UWB slave antennas were placed in the indoor area.