DINGPOS: High sensitivity GNSS platform for deep indoor scenarios

Deep indoor scenarios are one of the most challenging areas of application for Global Navigation Satellite Systems (GNSS) in personal navigation devices. Especially severe signal attenuation, as well as heavy multipath constrain the use of GNSS in this environment. The project DINGPOS is focusing on the development of a platform for pedestrian users which can acquire and track GNSS signals also under most adverse indoor signal conditions. The main idea of the concept is the extension of the coherent signal integration time of the GNSS receiver to the length of several seconds, which increases the correlation gain significantly. To facilitate this goal, a very long and very precise signal replica is needed. Therefore the system must reproduce the user motion, the navigation message data bits and the satellite constellation precisely. Hence, the system uses a sensor suite of several state of the art indoor positioning sensors and innovative fusion algorithms. The integrating element of the system is a software receiver using Ultra-Tightly Coupling (UTC) implemented by vector tracking. The presented work was performed under the ESA funded contract DINGPOS, ESTEC Ctr. No. 20834.