The ATC system includes four subsystems: automatic train protection (ATP), automatic train driving (ATO), automatic train monitoring (ATS) or centralized dispatch (CTC), and computer Interlocking system.
The ATC system includes five principle functions: ATS function, interlock function, train detection function, ATP function and PTI (train identification) function.
(1) ATS function: It is the core function of ATC, which can automatically or manually control the route, conduct traffic dispatch command, and provide information to the traffic dispatcher and external systems. The ATS function is mainly implemented by equipment located in the OCC (Control Center).
(2) Interlock function: In response to commands from the ATS function, under the premise of meeting safety guidelines at any time, manage the control of access roads, turnouts and signals, and integrate access roads, track circuits, turnouts and signals And status information is provided to ATS and ATC functions. The interlocking function is realized by equipment distributed along the track.
(3) Train detection function: generally completed by the track circuit.
(4) ATP function: under the constraint of interlocking function, realize the control of train operation according to the requirements of ATS. The ATP function has three sub-functions: ATP/ATO trackside function, ATP/ATO transmission function and ATP/ATO vehicle-mounted function. ATP/ATO trackside function is responsible for train interval and message generation; ATP/ATO transmission function is responsible for sending induction signals, which include messages and other data required by ATC on-board equipment; ATP/ATO on-board function is responsible for safe operation of trains and trains Autopilot, and provide interfaces for the signal system and the driver.
(5) PTI function: It transmits and receives various data through multiple channels, transmits it to ATS at a specific location, and reports train identification information, destination number, crew number and train location to ATS Data to optimize train operation.