Automatic train control system and corresponding method

An automatic train control system of the type with communication-based train management, including a ground component, called a ground ATC, and an on board component that is on board a train, called an on board ATC, wherein the on board ATC is able to be switched from an “active” operating mode to a “standby” operating mode and vice versa through a wake-up unit, and in that, in the “standby” operating mode, only the following components remaining supplied with electricity using an electrical power source:

• an odometry device measuring a movement of the train;
• a main computer;
• and
• a radio communication device between the on board ATC and the ground ATC;
• wherein the main computer being programmed so as, in the “standby” operating mode, to verify that the movement of the train measured by the odometry device from a switching moment from the “active” operating mode to the “standby” operating mode is zero and, in the affirmative, to send the ground ATC an instantaneous position of the train using the radio communication device, at least at a switching moment from the “standby” operating mode to the “active” operating mode.