An Adaptive Fused System of GNSS and Enhanced DR

When the vehicle traverses urban canyons such as valleys, tunnels and underground garages, the positioning accuracy decreases significantly, potentially leading to signal loss. This paper presents an optimised Dead Reckoning (DR) system consisting of a heading projection subsystem and a wheel speed sensor. The heading projection subsystem includes an inertial measurement unit (IMU) and a geomagnetometer to derive a stable, accurate heading angle. Trajectory projection is achieved by integrating speed data from the wheel speed sensor. An adaptive decision making process then evaluates this data, enabling independent calibration of the DR system and GNSS under varying conditions to maintain the integrity of the vehicle's positioning information during GNSS signal degradation or loss.