Navigation of Vehicle in Urban Canyon Via Two-Satellite GNSS and Map Aiding

The urgency of reliable navigation for manned and self-driving vehicles in urban environment is growing. The de facto standard of mass-produced navigation systems is global navigation satellite system (GNSS). Standalone work of a GNSS receiver is possible while receiving at least 4 signals from different navigation satellites. Operating of GNSS receiver in an "urban canyon" is broken due to the well-known problem of occlusions and reflections of navigation signals by tall buildings. A number of approaches are proposed to support integrity and reliability of navigation in difficult urban environment. In this paper, we propose a new approach that ensures the existence of a GNSS navigation solution even while receiving signals from only two navigation satellites. The proposed approach requires knowledge of the city map, which is easily realized in modern navigation equipment. The proposed approach is software implemented and doesn't change the hardware part of a GNSS receiver.