Integration of Barometric Height into RTK Positioning for Fast Ambiguity Refixing

The horizontal positioning accuracy of Global Navigation Satellite System receivers is in general two times higher than the vertical positioning accuracy. The integration of barometric height information improves in particular the vertical positioning accuracy. In this paper, we integrate differential air pressure measurements into Real-Time Kinematic (RTK) positioning with a Kalman filter. W e show that t he d ifferential a ir pressure measurements enable a faster convergence of the float RTK solution and a more reliable ambiguity fixing. $T$ hereby, the proposed method is especially attractive for improving the RTK performance after temporary GNSS outages.