The technologies that will be used in the future are not yet selected. It is clear that, when thinking about technologies currently available, LTE is the first one that comes to our minds. However, at the moment, there are a number of uncertainties that do not allow to get to that conclusion.
There is no evidence that LTE can support voice and data traffic when moving at high speeds (over 250 km/h) with an adequate performance. The current LTE specification does not fulfil all the railway requirements (e.g. railway emergency calls, group calls, priority and pre-emption) although the latter are planned to be included in the next LTE Releases (13 and above), to be commercially available in some years. In addition, railways are entitled to use a spectrum band that is not included in the current LTE specification and the reliability of the network has to be sufficient to cope with the RAMS requirements for railways.
A number of communication services can be made available to railways by using today’s LTE commercial networks, but this is not yet possible for the railway operational communications.
Finally, in the current EU legal framework, the use of GSM-R is mandated for railway operational communications.