Galileo for railway operations: question about the positioning performances analogy with the RAMS requirements allocated to safety applications

摘要

Purpose GNSS is penetrating, surely but certainly, the railway market. Introduction is performed through non safety oriented applications such as fleet management or passenger information. However, a huge panel of safety applications could take advantage of this technology. Galileo will soon complement the navigation satellite offer, monopolized today by GPS. Some issues have to be studied before safety uses: performance requirements have to be expressed; cost benefit analysis has to prove advantages compared to installed equipment... But one of the main issues concerns safety proofs that have to be in accordance with European railway standards. Methods Today, Galileo is not yet deployed but specifications are available. However, such specifications have been mainly driven by aeronautics. This paper deals with the question of the RAMS evaluation of the satellite-based location function delivered to a railway safety application, as recommended by railway standards and presents a methodology to transpose GNSS specifications into RAMS. Results It explains each definition of performance and demonstrates the relations between the Galileo SoL performances and the railway RAMS attributes. Conclusions GNSS are a powerful tool to enhance railway efficiency when its adequacy with railway specifications will be proved. This paper is a contribution to this effort.