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80-619: Communications Based Train Control (CBTC) and Transmission Based Signalling (TBS) are two signalling standards that can detect the exact location of trains and to transmit back the permitted operating speed to enable this flexibility. The European Train Control System ( ETCS ) also has the technical specifications to allow moving block operations, though no system is uses it currently, besides test tracks. Information about train location can be gathered through active and passive markers along

160-413: A moving block system as shown in the second figure, the train position and its braking curve is continuously calculated by the trains, and then communicated via radio to the wayside equipment. Thus, the wayside equipment is able to establish protected areas, each one called Limit of Movement Authority (LMA), up to the nearest obstacle (in the figure the tail of the train in front). Movement Authority (MA)

240-409: A Frequency Spectrum for Critical Safety Applications dedicated to Urban Rail Systems) to reserve a frequency band specifically for radio-based urban rail systems. Such decision would help standardize CBTC systems across the market (a growing demand from most operators) and ensure availability for those critical systems. As a CBTC system is required to have high availability and particularly, allow for

320-560: A Level 2-equipped train. A route is locked based on the national principles by the interlocking system and the RBC is informed about the routes set. The RBC checks whether it is possible to allocate a train to the route and then informs the interlocking system that a train is allocated to the route. The interlocking system may show the ETCS white bar aspect to signals at the ETCS Border or along

400-488: A better adaptation of the transport offer to the actual demand, allows significant energy savings reducing the power consumption. The primary risk of an electronic train control system is that if the communications link between any of the trains is disrupted then all or part of the system might have to enter a failsafe state until the problem is remedied. Depending on the severity of the communication loss, this state can range from vehicles temporarily reducing speed, coming to

480-484: A buffer to account for this, so trains might be 10 to 30 metres off the ideal, or "perfect" positioning. This helps to account for the transmission delays, and the slight inconsistency in train positioning calculations. Additionally, transmission between the train and the signalling system isn't literally continuous, instead it is sent as packages of information on the order of several times per second, to as infrequently as several seconds between transmissions. What this means

560-507: A careful analysis of the benefits and risks of a given CBTC architecture (centralized vs. distributed) must be done during system design. When CBTC is applied to systems that previously ran under complete human control with operators working on sight it may actually result in a reduction in capacity (albeit with an increase in safety). This is because CBTC operates with less positional certainty than human sight and also with greater margins for error as worst-case train parameters are applied for

640-547: A development plan first mentioned the creation of the European Rail Traffic Management System . In 1996 the first specification for ETCS followed in response to EU Council Directive 96/48/EC99 on interoperability of the trans-European high-speed rail system . The functional specification of ETCS was announced In April 2000 as guidelines for implementation in Madrid . In autumn 2000

720-544: A fully redundant architecture of the CBTC system may however achieve high availability values by itself. In principle, CBTC systems may be designed with centralized supervision systems in order to improve maintainability and reduce installation costs. If so, there is an increased risk of a single point of failure that could disrupt service over an entire system or line. Fixed block systems usually work with distributed logic that are normally more resistant to such outages. Therefore,

800-418: A graceful degradation, a secondary method of signaling might be provided to ensure some level of non-degraded service upon partial or complete CBTC unavailability. This is particularly relevant for brownfield implementations (lines with an already existing signalling system) where the infrastructure design cannot be controlled and coexistence with legacy systems is required, at least, temporarily. For example,

880-573: A halt or operating in a degraded mode until communications are re-established. If communication outage is permanent some sort of contingency operation must be implemented which may consist of manual operation using absolute block or, in the worst case, the substitution of an alternative form of transportation . As a result, high availability of CBTC systems is crucial for proper operation, especially if such systems are used to increase transport capacity and reduce headway. System redundancy and recovery mechanisms must then be thoroughly checked to achieve

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960-509: A high robustness in operation. With the increased availability of the CBTC system, there is also a need for extensive training and periodical refresh of system operators on the recovery procedures . In fact, one of the major system hazards in CBTC systems is the probability of human error and improper application of recovery procedures if the system becomes unavailable. Communications failures can result from equipment malfunction, electromagnetic interference , weak signal strength or saturation of

1040-529: A moving block railway system are: Moving block signalling could not effectively be implemented until the invention of reliable systems to communicate both ways between a train and a signalling system. While such technically has existed for decades, the impracticality of early technology a system made it unviable for many years. Pulse codes were used on the first version of the London Underground Victoria line 's signalling system. However,

1120-465: A moving block system knows where a train is, is from the train's own identification of where it is. Traditionally signalling systems use external means, such as axle counters and track circuits to determine the location of a train. What this means is that most trains have no way of positively confirming that the entire train is still connected. Such systems can easily be added to multiple unit passenger trains, especially if they are very rarely separated, but

1200-426: A pulse code two-way communication system using the computational technology at the time would have been complicated, so a fixed block system was used instead. Train integrity, while not a complicated problem on short suburban and metro lines, becomes a much more difficult problem when dealing with a variety of different train types, train lengths, and locomotive hauled trains (as opposed to Multiple Units). The only way

1280-469: A requirement for moving block operation. That said, the overwhelming majority of moving block systems use a signalling system consistent with the IEEE 1474 (1999) standard. Many different manufactures create systems consistent with the IEEE 1474 standard, and very few of them (if any) are compatible with each other. Transmission-based Train Control (TBTC) is an earlier form of CBTC that used induction loops on

1360-425: A route currently assigned for optical authorisation (e.g. after Start Of Mission (SOM) procedure or when the driver changes level from Level NTC to Level 2), the optical authorisation is automatically upgraded to a Level 2 movement authority. Consequently, a Level 2 movement authority is downgraded to an optical authorisation after a predefined time-out if the driver closes the cab or a fault is detected that restricts

1440-757: A variety of applications as shown in the figure below (mid 2011). They range from some implementations with short track, limited numbers of vehicles and few operating modes (such as the airport APMs in San Francisco or Washington ), to complex overlays on existing railway networks carrying more than a million passengers each day and with more than 100 trains (such as lines 1 and 6 in Madrid Metro , line 3 in Shenzhen Metro , some lines in Paris Metro , New York City Subway and Beijing Subway , or

1520-452: Is a "continuous, automatic train control system utilizing high-resolution train location determination, independent from track circuits ; continuous, high-capacity, bidirectional train-to-wayside data communications; and trainborne and wayside processors capable of implementing automatic train protection (ATP) functions, as well as optional automatic train operation (ATO) and automatic train supervision ( ATS ) functions," as defined in

1600-645: Is also used by the Hong Kong MTR , on the Tuen Ma line , Disneyland Resort line , South Island line and the East Rail line . It was supposed to be the enabling technology on the modernisation of Britain's West Coast Main Line which would allow trains to run at a higher maximum speed (140 mph or 230 km/h), but the technology was deemed not mature enough, considering the large number of junctions on

1680-529: Is commonly known to have three levels: Level 1 (an ATP system only); Level 2 (a virtual block system that can also be provided with Automatic Train Operation (ATO)); and Level 3 (similar to Level 2 but uses moving block and can do away with a lot of the lineside equipment. In practice level 3 is not yet used, and this has become an extension of Level 2. Equipment is produced by various manufactures, but this standard has protocols and therefore all ETCS equipment

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1760-426: Is compatible, unlike CBTC systems. Theoretically moving block can provide capacity advantages compared to fixed block systems, however in practice such advantages are difficult to fully realise. The main reason for this is a combination of the way railway networks practically operate, and tolerances within the moving block system. While a moving block system can technically allow a train to get as close as it can to

1840-473: Is considered as a basic enabler technology for this purpose. There are four grades of automation available: CBTC systems allow optimal use of the railway infrastructure as well as achieving maximum capacity and minimum headway between operating trains, while maintaining the safety requirements. These systems are suitable for the new highly demanding urban lines, but also to be overlaid on existing lines in order to improve their performance. Of course, in

1920-474: Is done by replacing former national signalling equipment and operational procedures with a single new Europe-wide standard for train control and command systems. The development process was started with the technical foundations for communication (GSM-R) and signalling (ETCS). Both are well established and in advanced public implementation worldwide . Now it begins to start attention for the 3rd part of ETML i.e. for fleet management or passenger information. In

2000-436: Is evolving, making use of the latest techniques and components to offer more compact systems and simpler architectures. For instance, with the advent of modern electronics it has been possible to build in redundancy so that single failures do not adversely impact operational availability. Moreover, these systems offer complete flexibility in terms of operational schedules or timetables, enabling urban rail operators to respond to

2080-561: Is in practice, is that movement authority is given as several metre sections at a time, often with a buffer and a slight delay from the actual position of the train ahead. Therefore, a similar level of performance could be achieved using fixed, but very small blocks. This is in fact how the Moscow Metro , and London Underground Victoria Line operate. They do not have moving blocks, merely a very high number of closely spaced "virtual" blocks. These networks are often considered to be two of

2160-476: Is mixed with NTC of ASFA and LZB . Operational principle of ETCS in mixed operation: NTC and ETCS Level 2 The principle of mixed level signalling is based on simple principles using bi-directional data exchange between the Radio Block Centre (RBC) and the interlocking systems. The operator sets a route and does not need to know if the route will be used for a Level NTC (former LSTM) only or

2240-483: Is possible even without moving block. Moving block can increase the capacity of a line if this limitation is removed from the system, which purportedly has been done on some railway networks, such as the Hong Kong MTR and at some stations, under certain conditions on the New York City Subway 's BMT Canarsie Line ( L train), however there is no verification of this available. Additionally, if it

2320-567: Is possible to run a line with both conventional and ETCS trains and to use the advantages of ETCS technology for the trains so equipped (e.g. higher speed or more trains on the line) but with the benefit that it is not necessary to equip the whole train fleet with ETCS simultaneously. Examples of ETCS in mixed operation include HSL 3 in Belgium where ETCS is mixed with national ATP system TBL or High-Speed Line Cordoba-Malaga in Spain where ETCS

2400-449: Is sortable, and is initially sorted by year. Click on the [REDACTED] icon on the right side of the column header to change sort key and sort order. 2021 (Tuen Ma Line and former West Rail Line) Brownfield (other sections) Greenfield (other sections) Line M4: UTO Line 5, Kelana Jaya Line Line 12, Putrajaya Line European Rail Traffic Management System The European Rail Traffic Management System ( ERTMS )

2480-459: Is the location to which the train is permitted to proceed according to a MA. When transmitting a MA, it is the end of the last section given in the MA. The RBC sends a Movement Authority (MA) to the train if a Level 2 train is allocated to the route. Otherwise the signal shows the optical proceed aspect and the related NTC code is sent to the track. As soon as a Level 2 train reports itself in rear of

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2560-419: Is the permission for a train to move to a specific location within the constraints of the infrastructure and with supervision of speed. End of Authority is the location to which the train is permitted to proceed and where target speed is equal to zero. End of Movement is the location to which the train is permitted to proceed according to an MA. When transmitting an MA, it is the end of the last section given in

2640-728: Is the system of standards for management and interoperation of signalling for railways by the European Union (EU). It is conducted by the European Union Agency for Railways (ERA) and is the organisational umbrella for the separately managed parts of The main target of ERTMS is to promote the interoperability of trains in the EU. It aims to greatly enhance safety, increase efficiency of train transports and enhance cross-border interoperability of rail transport in Europe . This

2720-402: Is the use of leaky feeder cable that, while having higher initial costs (material + installation) achieves a more reliable radio link. With the emerging services over open ISM radio bands (i.e. 2.4 GHz and 5.8 GHz) and the potential disruption over critical CBTC services, there is an increasing pressure in the international community (ref. report 676 of UITP organization, Reservation of

2800-493: Is varying according to the continuous updates of the train location and speed, maintaining the safety requirements. This results in a reduced headway between consecutive trains and an increased transport capacity . Modern CBTC systems allow different levels of automation or grades of automation (GoA), as defined and classified in the IEC 62290–1. In fact, CBTC is not a synonym for " driverless " or "automated trains" although it

2880-599: The BMT Canarsie Line in New York City was outfitted with a backup automatic block signaling system capable of supporting 12 trains per hour (tph), compared with the 26 tph of the CBTC system. Although this is a rather common architecture for resignalling projects, it can negate some of the cost savings of CBTC if applied to new lines. This is still a key point in the CBTC development (and is still being discussed), since some providers and operators argue that

2960-478: The IEEE 1474 standard. CBTC is a signalling standard defined by the IEEE 1474 standard. The original version was introduced in 1999 and updated in 2004. The aim was to create consistency and standardisation between digital railway signalling systems that allow for an increase in train capacity through what the standard defines as high-resolution train location determination. The standard therefore does not require

3040-711: The Singapore North East Line . CBTC has its origins in the loop-based systems developed by Alcatel SEL (now Thales ) for the Bombardier Automated Rapid Transit (ART) systems in Canada during the mid-1980s. These systems, which were also referred to as transmission-based train control (TBTC), made use of inductive loop transmission techniques for track to train communication, introducing an alternative to track circuit based communication. This technology, operating in

3120-416: The signalling system perspective, the first figure shows the total occupancy of the leading train by including the whole blocks which the train is located on. This is due to the fact that it is impossible for the system to know exactly where the train actually is within these blocks . Therefore, the fixed block system only allows the following train to move up to the last unoccupied block 's border. In

3200-544: The 30–60  kHz frequency range to communicate trains and wayside equipment, was widely adopted by the metro operators in spite of some electromagnetic compatibility (EMC) issues, as well as other installation and maintenance concerns (see SelTrac for further information regarding transmission-based train-control). As with new application of any technology, some problems arose at the beginning mainly due to compatibility and interoperability aspects. However, there have been relevant improvements since then, and currently

3280-484: The ERTMS-route. Depending on the implementation, NTC systems along the route may or may not be active. Movement Authority (MA) is the permission for a train to move to a specific location within the constraints of the infrastructure and with supervision of speed. End of movement Authority (EoA) is the location to which the train is permitted to proceed and where target speed is equal to zero. End of movement Authority

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3360-447: The ETCS and ATC balise frequencies are too close so that older trains would get faults when passing Eurobalises . Mixed operation is a strategy where the wayside signalling is equipped with both ETCS and a conventional Class B system. Often the conventional system is the legacy system used during the signalling upgrade program. The main purposes of introducing a mixed operation (mixed signalling system) are: With mixed operation it

3440-463: The MA. It is important to mention that the occupancy calculated in these systems must include a safety margin for location uncertainty (in yellow in the figure) added to the length of the train. Both of them form what is usually called 'Footprint'. This safety margin depends on the accuracy of the odometry system in the train. CBTC systems based on moving block allows the reduction of the safety distance between two consecutive trains. This distance

3520-565: The Sub-Surface network in London Underground ). Despite the difficulty, the table below tries to summarize and reference the main radio-based CBTC systems deployed around the world as well as those ongoing projects being developed. Besides, the table distinguishes between the implementations performed over existing and operative systems ( brownfield ) and those undertaken on completely new lines ( Greenfield ). This list

3600-693: The UIC ERTMS World Conference in Stockholm, Sweden, the executive director of the Community of European Railway and Infrastructure Companies (CER) called for an accelerated implementation of ERTMS in Europe. After definition of ETCS Baseline 3 in about 2010 and starting of implementation in multiple countries with Baseline 3 Release 2 in summer 2016, it is again possible to direct attention to operational management requirements of payloads . Logistics companies like DB Cargo have

3680-413: The ability to determine their own speed, this information can be combined and transmitted to the external signalling computer (at a rail operations centre). Using a combination of time and speed, the computer can add the time since the train passed the transponder, and the speeds it has travelled at during that time, to then calculate exactly where the train is, even if it is between transponders. This allows

3760-645: The case of upgrading existing lines the design, installation, test and commissioning stages are much more critical. This is mainly due to the challenge of deploying the overlying system without disrupting the revenue service. The evolution of the technology and the experience gained in operation over the last 30 years means that modern CBTC systems are more reliable and less prone to failure than older train control systems. CBTC systems normally have less wayside equipment and their diagnostic and monitoring tools have been improved, which makes them easier to implement and, more importantly, easier to maintain. CBTC technology

3840-414: The communications medium. In this case, an interruption can result in a service brake or emergency brake application as real time situational awareness is a critical safety requirement for CBTC and if these interruptions are frequent enough it could seriously impact service. This is the reason why, historically, CBTC systems first implemented radio communication systems in 2003, when the required technology

3920-454: The design (e.g. guaranteed emergency brake rate vs. nominal brake rate). For instance, CBTC introduction in Philly's Center City trolley tunnel resulted initially in a marked increase in travel time and corresponding decrease in capacity when compared with the unprotected manual driving. This was the offset to finally eradicate vehicle collisions which on-sight driving cannot avoid and showcases

4000-639: The difficulty in achieving this means that the system has not yet been implemented. Communications-based train control Communications-based train control ( CBTC ) is a railway signaling system that uses telecommunications between the train and track equipment for traffic management and infrastructure control. CBTC allows a train's position to be known more accurately than with traditional signaling systems. This can make railway traffic management safer and more efficient. Rapid transit system (and other railway systems) are able to reduce headways while maintaining or even improving safety. A CBTC system

4080-422: The frequency of the same line, but with only two platforms at stations (one per direction) even if both lines use equivalent signalling systems. This reality means that most of the benefits of a moving block signalling system can only be achieved in and around stations. However, then consider that almost all railways have an operational requirement that a following train cannot begin to enter the train platform, until

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4160-496: The highest capacity railway lines in the world. The second reason why capacity is not necessarily improved, is because trains operating on a railway line with stations must make station stops. This time spent in a station means trains won't travel anywhere near as close to each other on 95% of the railway as they technically would be able to, if there were no stations. Consider that a two-track railway with four parallel platforms (2 per direction) at stations can have more or less double

4240-401: The implementation of technology to do the same with locomotive hauled trains is significantly more involved. Every effective solution would require expensive technology, the cost of which may outweigh the benefits of a moving block system. Another version of the moving block system would be to locate computers solely on the trains themselves. Each train determines its location in relation to all

4320-527: The introduction of ETCS Level 1 (such as in Spain) proved to be expensive and nearly all implementations are delayed. The defined standards were comprehensive by political nature, but not exact in technical means. National rail authorities often had certain features or constraints in their existing system they did not want to lose, and since every authority was still required to approve the systems, dialects of ERTMS emerged. Some active players were willing to overcome

4400-471: The introduction of ETCS the infrastructure manager has to decide whether a line will be equipped only with ETCS or if there is a demand for a mixed signalling system with support for National Train Control (NTC). Currently, both 'clean' and mixed systems are being deployed in Europe and around the world. Many new ETCS lines in Europe are being created and then it may often be preferred to implement ETCS Level 1 or Level 2 only. With this implementation strategy

4480-484: The line, and the plan was dropped. Current implementations of Moving block have only been effectively proven on segregated networks with few junctions. The European Rail Traffic Management System 's level-3 specification (naming on this has recently changed) for the European Train Control System , aims to provide a more robust version of moving block which can work with complex railways, however

4560-739: The member states of EU voted for publication of this specifications as decision of the European Commission to get a preliminary security in law and planning. This was to give the foundation for testing applications in six member railways of the ERTMS Users Group . In 2002 the Union of Signalling Industry (UNISIG) published the SUBSET-026 defining the current implementation of ETCS signalling equipment together with GSM–R – this Class 1 SRS 2.2.2 (now called ETCS Baseline 2 )

4640-1085: The mid-1980s, the International Union of Railways (UIC) and the European Rail Research Institute (ERRI) began the search for a common European operation management for railways, titled ERTMS. Today the development of ERTMS is steered by the ERA and driven by the Association of the European Rail Industry (UNIFE, Union des Industries Ferroviaires Européennes). Until this effort began, there were (for historical reasons in each national railway system) in Europe: all influencing train communication in parts. To illustrate this, long running trains like Eurostar or Thalys must have 6 to 8 different train protection systems. Technical targets of ERTMS are: In 1995

4720-409: The modern CBTC systems the trains continuously calculate and communicate their status via radio to the wayside equipment distributed along the line. This status includes, among other parameters, the exact position, speed, travel direction and braking distance . This information allows calculation of the area potentially occupied by the train on the track. It also enables the wayside equipment to define

4800-404: The need to develop functional capabilities in the target scope of ETML, which should be welcome for standardisation. The deployment of the European Rail Traffic Management System means the installation of ETCS components on the lineside of the railways and the train borne equipment. Both parts are connected by GSM-R as the communication part. Various railway roll out strategies can be used. With

4880-421: The other trains and sets its safe speeds using this data. Less wayside equipment is required compared to the off-train system but the number of transmissions is much greater. "Moving block" is not technically a standard, rather it is a concept that can be implemented through multiple standards. CBTC is the most common associated standard, however CBTC as it is described in IEEE 1474 (1999) makes no mention of

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4960-418: The points on the line that must never be passed by the other trains on the same track. These points are communicated to make the trains automatically and continuously adjust their speed while maintaining the safety and comfort ( jerk ) requirements. So, the trains continuously receive information regarding the distance to the preceding train and are then able to adjust their safety distance accordingly. From

5040-556: The protected section for each train is a "block" that moves with and trails behind it, and provides continuous communication of the train's exact position via radio, inductive loop, etc. As a result, Bombardier opened the world's first radio-based CBTC system at San Francisco airport 's automated people mover (APM) in February 2003. A few months later, in June 2003, Alstom introduced the railway application of its radio technology on

5120-398: The rear of the previous train has completely departed. This acts as a "fixed" block even on moving block systems, and will necessarily limit the throughput of the line to only that which is possible using conventional signalling practices. Most of the benefit networks gain from using moving block actually comes from the increased consistency of train movement, one gets from ATO . However, ATO

5200-485: The reliability of the radio-based communication systems has grown significantly. Moreover, it is important to highlight that not all the systems using radio communication technology are considered to be CBTC systems. So, for clarity and to keep in line with the state-of-the-art solutions for operator's requirements, this article only covers the latest moving block principle based (either true moving block or virtual block , so not dependent on track-based detection of

5280-749: The same headway capacity using the large amount of additional equipment it would take to do it with fixed or virtual block systems. Moving block is in use on several London Underground lines, including the Jubilee , and Northern lines, and parts of the sub-surface lines . In London it is also used on the Docklands Light Railway and the core section of the Elizabeth line . New York City Subway 's BMT Canarsie Line ( L train), Tren Urbano (Puerto Rico), Singapore's MRT , and Vancouver's SkyTrain , also employ moving block signalling. It

5360-410: The signalling system to then give a following train a movement authority, right up to the rear end of the first train. As more information comes in, this movement authority can be continuously updated achieving the "moving block" concept. Each time a train passes a transponder, it re-calibrates the location allowing the system to retain accuracy. Technologically, the three most difficult parts to achieve

5440-595: The situation with a new Baseline definition, not suited for immediate action. This situation shifted the focus more onto the technical parts of ETCS and GSM-R as universal technical foundations of ERTMS. To master this situation, Karel Vinck was appointed in July 2005 as EU coordinator. In 2005 a Memorandum of Understanding on ERTMS was published by members of the European Commission, national railways and supplying industries in Brussels . According to this declaration ETCS

5520-480: The specific traffic demand more swiftly and efficiently and to solve traffic congestion problems. In fact, automatic operation systems have the potential to significantly reduce the headway and improve the traffic capacity compared to manual driving systems. Finally, it is important to mention that the CBTC systems have proven to be more energy efficient than traditional manually driven systems. The use of new functionalities, such as automatic driving strategies or

5600-403: The track for communication with the signalling system, rather than radio signals or some other method. The words Transmission and Communication and synonyms in some circumstances, so neither one of these names accurately describes what each standard is. List of systems considered to use TBTC are: ETCS is the signalling protocol for the European Rail Traffic Management System (ERTMS). This system

5680-436: The tracks, and train-borne tachometers and speedometers. Satellite-based systems are not used because they do not work in tunnels. Traditionally, moving block works by having a series of transponders in the rail corridor that each have a known location. When a train traverses over a transponder, it will receive the identification information allowing the train to know precisely where on the network it is. Because trains also have

5760-469: The train in front while still retaining enough space for it to be able to stop (using regular service brakes) should a further update to the movement authority not be received, in practice if a train was to drive this close to the train ahead, the tiny inconsistency between the movement authority updates would require frequent braking applications and likely result in the train naturally tending to travel further behind. Most moving block systems also operate with

5840-520: The trains) CBTC solutions that make use of the radio communications . CBTC systems are modern railway signaling systems that can mainly be used in urban railway lines (either light or heavy ) and APMs , although it could also be deployed on commuter lines . For main lines , a similar system might be the European Railway Traffic Management System ERTMS Level 3 (not yet fully defined ). In

5920-414: The use of moving block railway signalling, but in practice this is the most common arrangement. Traditional signalling systems detect trains in discrete sections of the track called ' blocks ', each protected by signals that prevent a train entering an occupied block. Since every block is a fixed section of track, these systems are referred to as fixed block systems. In a moving block CBTC system

6000-401: The usual conflicts between operation and safety. The typical architecture of a modern CBTC system comprises the following main subsystems: Thus, although a CBTC architecture is always depending on the supplier and its technical approach, the following logical components may be found generally in a typical CBTC architecture: CBTC technology has been (and is being) successfully implemented for

6080-782: The wayside signalling cost is kept to a minimum, but the vehicle fleet that operates on these lines will need to all be equipped with ETCS on board to allow operation. This is more suitable for new high-speed passenger lines, where new vehicles will be bought, less suitable if long-distance freight trains shall use it. Examples of 'clean' ETCS operation include HSL-Zuid in the Netherlands, TP Ferro international stretch (Sección Internacional / Section Internationale ) Figueres [ES] – Perpignan [FR], Erfurt–Halle/Leipzig in Germany , among others. Also all ETCS railways in Sweden and Norway, since

6160-487: Was accepted by the European Commission in decision 2002/731/EEC as mandatory for high-speed rail and in decision 2004/50/EEC as mandatory for conventional rail. In 2004 further development stalled. While some countries ( Austria , Spain , Switzerland ) switched to ETCS with some benefit, German and French railway operators had already introduced proven and modern types of domestic train protection systems for high speed traffic, so they would gain no benefit. Furthermore,

6240-413: Was mature enough for critical applications. In systems with poor line of sight or spectrum/bandwidth limitations a larger than anticipated number of transponders may be required to enhance the service. This is usually more of an issue with applying CBTC to existing transit systems in tunnels that were not designed from the outset to support it. An alternate method to improve system availability in tunnels

6320-456: Was permissible to give the following train movement authority past the rear of the leading train (up to the point where the rear of the leading train would end up if its emergency brakes were applied) capacity could be further increased. However, this has never been done and is currently considered unsafe. Instead, the advantage of Moving block systems generally is that of decreased lineside equipment, which can save money in comparison to achieving

6400-691: Was to be introduced in 10 to 12 years on a named part of the Trans-European Networks . Following this a conference was held in April 2006 in Budapest for the introduction of ERTMS, attended by 700 people. In July 2009, the European Commission announced that ETCS is now mandatory for all EU funded projects which include new or upgraded signalling and GSM-R is required when radio communications are upgraded. In April 2012 at

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