Verification of quantitative requirements for GNSS-based railway applications

摘要

The objective of this paper is to verify whether requirements for GNSS-based railway telematic applications are met through GNSS Safety of Life (SoL) services. Measurement methodology was developed for this purpose. An analysis of the achievement of railway requirements was subsequently performed. This technique represents a contribution to the certification process of the GNSS system, which must prove that the required parameters are fulfilled. The analysis consists of: 1) evaluation of static measurements to verify GNSS system behaviour under standard conditions of GNSS Signal-In-Space (SIS) reception, and 2) analysis of dynamic tests focused on train position and protection level determination under variable conditions of GNSS SIS reception in a real railway environment. Experimental tests have been carried out using GPS/EGNOS receivers that meet requirements for the SoL service according to the RTCA DO-229D standard.