intermittent and continuous ATP 101119 - irse.nl

Euroloop locationsLevel 2 would be the normal choice for main lines, being similar in performanceto the LZB and TVM type of systems. As the GSM-R radio is in most cases also usedfor voice transmission between driver and dispatcher, the cost of the radio systemcan be considered part of the communication system and therefore does not need tobe justified solely by the ATP/ATC system. This can make ERTMS/ETCS level 2systems more cost effective than many of the existing continuous ATC systems inEurope. The number of lineside signals can be significantly reduced and be replacedby cab signalling. There is, however, the required availability and the fallback strategyin case of a failure to be considered.As Level 3 systems of ERTMS/ETCS operate without lineside signals and trackbased train detection systems are made redundant by active reporting of the trainposition. The train integrity supervision is therefore a vital function, which up to nowdoes not have convincing technical solutions for freight trains. If this technicalproblem can be overcome in the future, level 3 offers an implementation whichshould be very effective in terms of investment and maintenance cost, but also interms of Occupational Health and Safety as it reduces the amount of equipmentmounted close to or even inside the fouling gauge.The mode of operation of a level 3 system can be either fixed block, where linecapacity is not critical or moving block for minimised train headway.To facilitate the migration to ERTMS/ETCS whilst the required maintaininginvestment at an affordable level, some railways, most notably the Swiss, advocate aLimited Supervision level of application to be added to the standard which wouldrequire only a limited number of signals to be equipped and the UIC still pursues aregional ERTMS project.44