It has been a couple of years since I worked in the area, but back then that wasn’t the plan and would’ve been deemed impossible both for safety and for accuracy reasons. Do you maybe have a source?
> A failsafe on-board multi-sensors localisation unit consisting of a navigation core (IMU, tachometer, etc.) brought in reference using GNSS, track map and a minimal number of reference points
> to complement the existing European Train Control System (ETCS) odometry system by using GNSS to enable absolute safe train positioning whilst also transforming today’s train localisation by demonstrating a GNSS based multi-sensor fusion architecture.
Okay, so as I expected they want to add GNSS as an additional sensor input. That is useful because without it train odometry is purely relative and the train doesn't know where it is until is reads the first balise. The plan doesn't seem to be to remove all other sensors. Denial of GNSS would then mean that start-of-mission is about as tedious as it is today and odometry accuracy might be reduced. Depending on the number of balises on the track that lowers the capacity of the track a little but is far from catastrophic.
I see a balise antenna even in the „long term“ architecture diagram and don’t have the time to parse ninety pages of technical documentation. Of course I wouldn’t be surprised if they went to reduce the number of balises, but I don’t think it’s possible to go completely without.
