Satellite availability in a railway mountainous environment : Can we use satellite positioning for safety applications ?

The arrival of GALILEO will provide to railways a localisation solution, civil, European, interoperable with the existing GPS. The use of both systems and the characteristics of GALILEO open the way to new applications, and particularly to safety related applications. However the reception of satellite signals depends on the environment around the antenna and can degrade the typical performance of such systems. The PREDISSAT tool based on video records permit to evaluate the satellite states of reception along a line. The study realised along a mountainous line in the south of France illustrates the tool and typical results obtained.