Satellite based Rail Traffic Management System

In 2019, around 1 500 significant railway accidents were reported in Europe. The ESA-backed 3InSat project aims to develop and validate a new satellite-based platform to be integrated into a European Rail Traffic Management System to prevent accidents due to human errors and increase railway safety.

Source: Eurostat

Modern railway signalling systems play a major role in providing safety networks to prevent accidents due to human errors. Furthermore, railways traffic management systems improve the utilisation of scarce and expensive resources like the railways infrastructure. One of the major breakthroughs has been the introduction of an interoperable European standard known as the European Rail Traffic Management System (ERTMS), which not only allows speed limits to be transmitted to the driver, but can also continuously monitor the driver's response to this information. An on-board computer effectively compares the speed of the train with the maximum permitted speed and automatically applies the train's braking, if the limit is exceeded. The wider implementation of the ERTMS requires significant investments in ground infrastructure (used for both positioning and telecommunication purposes). So far, high speed lines and international freight transport lines have been the primary target for these systems, which are implemented using infrastructure deployed along the rail tracks (e.g. balises (electronic beacons), track circuits, cablings, GSM-R network) that are expensive to procure, install and maintain. Such highly expensive infrastructure has so far prevented the adoption of advanced train traffic management systems in regional and remote railways lines, where traffic levels are typically low. Both railways and train operators are interested in the introduction of advanced safety systems along this type of lines, which therefore still represents an untapped market. A promising way to reduce the costs associated with the implementation and maintenance of ERMTS compatible solutions is to reduce the extent of deployment of the track side infrastructure using SatNav and SatCom to complement or replace the ground-based infrastructure. 3InSat is a project that aimed to develop and validate a new satellite-based platform to be integrated into an ERTMS system. This satellite supported solution is not yet available on the market because of the very challenging safety requirements (Safety Integrity Level 4 SIL4 requirement) that a railway signalling system needs to comply with. A validation campaign is planned on a specific test site to be carried out in Sardinia on a 50-km stretch.