Division 2.2.3 Levels of Application (ERTMS/ETCS)
United Kingdom
The interfaces specified by this TSI define the means of data transmission to, and sometimes from, trains. The Class A specifications referenced by this TSI provide options from which a project may choose the means of transmission that meet its requirements. Three levels of application are defined:
Data transmission is achieved by spot transmission (Eurobalise) and in some cases by semi-continuous transmission (Euroloop or radio in-fill). The detection of trains is achieved by track-based equipment, usually track-circuits or axle counters. Signalling information is communicated to the driver by equipment in the driving cab and, optionally, lineside signals.
Data transmission is achieved by continuous radio transmission (GSM-R). For some functions, the radio transmission requires complementing by spot transmission (Eurobalise). The detection of trains is achieved by track-based equipment, usually track-circuits or axle counters. Signalling information is communicated to the driver by equipment in the driving cab and, optionally, lineside signals.
Data transmission is achieved by continuous radio transmission (GSM-R). For some functions, the radio transmission requires complementing by spot transmission (Eurobalise). The detection of trains is achieved by equipment on-board, reporting to the Control-Command Track-side Assembly. Signalling information is communicated to the driver by equipment in the driving cab.
The requirements of this TSI apply to all levels of application. Implementation is addressed in Chapter 7 (Implementation of the TSI Control-Command). A train equipped with a Class A On-board system for a given level of application shall be able to operate on that level and any lower one.