The system that monitors and provide necessary commands to direct the operation of Trains in order to maintain the schedule in the required traffic patterns to minimise the effect of Train delays. Automatic Train Supervision System (ATS) is part of the Automatic Train Control (ATC) along with Automatic Train Protection System(ATP) .Refer Figure 1 for  the relation .Primary Function of an Automatic Train Supervision(ATS)  is to control and monitor the train operation .ATS is managing the train operation according to a time table or a specific headway or based on human (operator ) interaction on degraded mode of operation. A modern day ATS includes Automatic Train Regulation (ATR) and a Schedule Compiler.

Figure :1 Block Diagram of Automatic Train Control

ATS provide interface for the operator to supervise and manage trains. It provide real time status of the operating positions of the trains. ATS control launching of trains from storage facility to the commercially operating line and return the trains from operating lines to storage facility. It can also send manual and automatic commands to initiate and terminate train operations with override automatic command functionality. Modern day ATS system has some of the following functionality.

1. Operator can create and modify timetables.
2. Operator can monitor and control real time trains
3. Automatically send route call requests according to train operation requirements
4. Automatically send traffic locking calls based on train operation requirements
5. Automatically regulate train movements based on regulation needs.
6. Allow restore services and re-establish train operating patterns due to service delays and breakdowns
7. Tracking Train Positions in all signalled area.
8. Manage events and alarms from signalling system, trains and other signalling subsystems.
9. Supply real time train information to Public addressing system.
10. Generate performance reports for train service availability and train service quality factor.
11. Allow automatic and manual taking over of control centres, if have multiple control centres for redundancy purpose.
12. Capable of remotely control to open and close train doors and Platform Screen Door, if present
13. Can build centralized functionality and localized functionality.
14. Can build Train Description Facility for tracking and maintain a record of each train.