A GNSS-based inverted radar for carrier phase absolute indoor positioning purposes first experimental results with GPS signals

The continuity of the positioning service, in all potential environments, and specifically from outdoors to indoors, is a fundamental aspect when one wants to increase the use of location-based services. Many techniques have so far been investigated, ranging from inertial systems to the latest light fidelity approaches. Besides these physical means, an aspect which is almost as important is the associated processing techniques: calculation methods, fusion algorithms, filtering, etc. This leads to our GNSS (Global Navigation Satellite System) based approach. The basic idea is to take advantage of the wide availability of such receivers and the strength of the related community of engineers and researchers. The principle is based on the so-called pseudolites (acronym for “pseudo satellites”) approach which consists in deploying local transmitters.