Contrôle de vitesse par balises

Contrôle de Vitesse par Balises (Speed control by beacons), abbreviated to KVB[note 1] is a train protection system used in France and in London St. Pancras International station.

[1] KVB consists of: The on-board computer generates two speed-thresholds based on the received signals from the balises.

If the second speed threshold is passed, the KVB automatically engages emergency brakes on the train.

The TGV is equipped with this system for all of its routes over conventional rail lines.

KVB is comparable to ETCS Level 1 Limited Supervision because it offers a beacon-based speed control without any indication for the driver.