The new ATC system using the digital transmission for super high speed operation on the Shinkansen lines

East Japan Railway Company (JR East) developed a new automatic train protection (called Automatic Train Control, ATC) system, which uses the continuous digital transmission for Shinkansen lines. In this system, such messages as the distance to the preceding train or the speed limit on switches are transmitted to each train. This is done through the rail using digital codes. On-board equipment verifies the train speed. If the speed exceeds the value of a calculated braking-pattern, the brake is applied. As the on-board equipment controls the train speed in one step from maximum speed to stop, this system can upgrade the maximum speed and shorten the train headway. It can effectively cope with a mixture of trains with different braking performances.