Detection of GNSS errors caused by local effects

Recent progress in the field of satellite navigation systems (GNSS, SBAS) supports effort to use it for the determination of train position for the railway safety-related systems. Firstly, current state of art in this field is mentioned in this paper. The key feature of localization from the point of view of safety-related applications in transportation is integrity. Proposed method for increasing integrity is investigated in this paper. The method is based on relation between horizontal and vertical GNSS errors. This method has been investigated by simulations of errors in pseudoranges (multipath). Simulation was based on real pseudoranges measured by GNSS receiver. According to results of simulation error in horizontal plane can be detected by known error in vertical plane with assumption that we know position in vertical plane.