Rail K&N

P44 - Data used by applications outside the ERTMS system

2023-01-12T20:47:00.001-08:00

The ERTMS/ETCS uses its own language to transmit information over radio or/and balise using variables, packets, messages, and telegrams. To allow flexible application, Packet 44 (P44) was specified in the Technical Specifications of Interoperability (TSI) for applications used outside the ERTMS/ETCS system.

The P44 can be used outside the ETCS application by associating with NID_XUSER, which is the variable that uniquely defines the identity number of a specific user system for which the remainder of P44 is intended. The NID_XUSER and P44 can be used for more than one purpose such as ASDO (Automatic Selective Door Operation ) and Speedo Meter Unit change.

Automatic Selective Door Operation (ASDO)

ASDO is a system that can be deployed with ETCS using Packet 44 to compare the length of the train with the length of the platform, sending a signal to the driver so that only the doors on the platform side are opened.

Automatic Selective Door Operation (ASDO)
Photo Credit: Petards Group

Platform information is transmitted by telegram that contains a set of packets including the P44 for each station platform by the balise group which contains information including but not limited to the side of the doors whether on the left or the right side and the length of the platform. This system is used in different countries like Australia (Transport for New South Wales), New Zealand (KiwiRail), and India (The National Capital Region Transport Corporation),... but they are deployed in different ways.

Automatic Train Operation - UK

In the United Kingdom, the Thameslink core section through Central London between St Pancras and Blackfriars became the first ATO route on the National Rail network in 2018. The Thameslink core represents the first deployment of ATO with the European Train Control System (ETCS), also called ATO over ETCS (AoE). The ATO in this project receives its timetable and regulation instructions via the Packet 44 telegram facility in the ETCS Eurobalise.

ATO-OB. Credit Govia Thameslink Railway (GTR)

Migration to ETCS

Switzerland has been the early adopter of ETCS to control trains. All rail vehicles in Switzerland are equipped with the so-called ETM (Eurobalise Transmission Module). This enables them to read and process information from the national SIGNUM and ZUB train control systems provided by Eurobalises and Euroloops (in packet 44).

Migration to ETCS. Credit Stefan Sommer

Speedo Meter Unit change

Alstom supported by partners at Network Rail, Grand Central and Angel Trains completed FiC testing and accumulated endurance running to prove the reliability of the Alstom ATLAS 2 ETCS onboard system. The Onboard ETCS system fitted to the Class 180 is the first onboard system tested at RIDC that is compliant with ETCS standard Baseline 3 Release 2 (required standard for ECDP rollout). The onboard system is the first to support Packet 44, which enables operation with GB specifics such as miles per hour.

ETCS-fitted Class 180 Train. Credit Network Rail

Sources:
23 EUG GDL Balise_Engineering v1.0 https://ertms.be/sites/default/files/ESG%20working%20Group/23%20EUG%20GDL%20Balise_Engineering%20v1.0.pdf
Presentation ERTMS / ETCS in Switzerland by Stefan Sommer, Head of Business Unit Train Control Systems, 01.11.2012
https://www.ft.dk/samling/20121/almdel/tru/bilag/133/1209684.pdf
Modern Railways, Thameslink putting ETCS to work
https://www.modernrailways.com/article/thameslink-putting-etcs-work
Rail Business Daily, Rail Innovation & Development Centre carries out its first ETCS retrofit train tests
https://news.railbusinessdaily.com/rail-innovation-development-centre-carries-out-its-first-etcs-retrofit-train-tests/

Railways Applications, Safety Integrity Level (SIL)

2022-02-04T12:12:00.003-08:00

The concept of Safety Integrity Level (SIL) is a direct result of the IEC 61508 standard, which is not specific to railways. For the railway industry, CENELEC (European Committee for Electrotechnical Standardization) has developed the standards EN 50126 (The Specification and Demonstration of Reliability, Availability, Maintainability and Safety (RAMS)), EN 50128 (Communication, signalling and processing systems - Software for railway control and protection systems), and EN 50129 (Communication, signalling and processing systems - Safety related electronic systems for signalling) which have been derived from the IEC 61508 standard to meet the specific requirements of the railways.

There are four Safety Integrity Levels, labelled from SIL 1 to SIL 4: The latter has the highest level of safety integrity and SIL 1 the lowest. The costs increase significantly to reach higher levels, so the cost of not implementing the appropriate SIL far exceeds the cost of the overall implementation.

The standard associates Safety Integrity Levels with numerical probabilities of hazardous failures in two tables, one for systems that operate continuously (Table 1) and the other one for systems that operate on-demand (Table 2).

Table 1: SIL - Continous Demand

Table 2: SIL - Low Demand

A low demand system, as defined by the standards, is 'no greater than one demand per year', hence the difference of 10(.^4) in the values in the two tables (where one year is approximated to 10(.^4) hours).

What does 'SIL 4 Certified System' mean? That means there is the probability of a single error in 10,000 years.

For Railway Signalling, usually, ATP (Automatic Train Protection) systems are SIL 4, ATO (Automatic Train Operation) systems are SIL 2, and ATS (Automatic Train Supervision) systems are SIL 2.

Evolution and beyond Railway Signals and Blocks

2022-01-27T13:43:00.003-08:00

First trains were pulled by horses or mules so they were slow and only a few ones. At that time, the first conventional signal appeared: a signalman mounted on a horse preceded some early trains. Hand and arm signals were used to direct the "train drivers." Foggy conditions and poor visibility later gave rise to flags and lanterns. The first form of blocks was created using a raised flag or ball signal that could be seen from a distance.

Some evolutions have occurred which led trains to run at a higher speed, approximately up to 60 km/h, which complicated its stop in case of emergency due for example to the low adhesion between rail and wheel in addition to serious problems to notice another train passing in front or in the other direction. It was, therefore, more and more a need to warn the driver of a train early enough of the presence of an obstacle to its route to prevent accidents and collisions.

Accidents were common in the early days of railroading. The first switchmans stood at intervals, which we called today blocks, along the line with stopwatches and manual signals to inform train drivers that a train has passed more or less than a certain number of minutes before. This process required considerable staff resources. This solution was not very effective as they had no way of knowing if a train had crossed the line ahead, so if a preceding train stopped for any reason, the crew of a following train would have no way of knowing unless it was clearly visible.

Then mechanical signals appeared to replace manual signals and they became later controlled by levers grouped in a signal box to control the correspondent blocks. Then they were followed by the signals that we know today.

Today, railway signalling is based on fully automatic blocks, with no need for manual intervention. A line equipped with automatic blocks is divided into several sections whose length is greater than the greatest train braking distance.

Detection of the train is used usually by a track circuit or axle counter and the continuous check of the speed of a train, if it is compatible with the permitted speed allowed by the signalling system, is done by the Automatic Train Protection (ATP)

Train Detection Systems

Automatic Train Protection (ATP)

Fixed Block

The track is divided into portions, called block sections or blocks, which normally admit only one train. Each block is protected by a signal placed at its entrance. Line and train speed, gradient, braking characteristics of trains, and other information should be provided to identify the length of the block.

The animation below illustrates well the principle of a fixed block but it needs some improvements for the distance of the block compared to the length of the train in addition to the speed.

Illustration of Fixed Block
Source: Murat Yukselir / The Globe and Mail

A disadvantage of fixed blocks is that if faster trains are allowed to run, they require longer stopping distances, which requires longer blocks, which decreases the capacity of the line. Fixed blocks must be sized for the worst-case stopping distance, regardless of the actual speed of the trains.

Moving Block

In a moving block system, computers calculate a "safety zone" around each moving train into which no other train is allowed to enter. The system depends on knowledge of the precise location, speed and direction of each train, which is determined by a combination of several sensors: active and passive markers along the track and on-board speedometers; (GPS systems cannot be relied upon because they do not work in tunnels). With a moving block configuration, line-side signals are unnecessary and instructions are transmitted directly to the trains. This has the advantage of increasing track capacity by allowing trains to run closer together while maintaining the required safety margins.

The animation below illustrates the principle of a moving block.

Illustration of Moving Block
Source: Murat Yukselir / The Globe and Mail

Unfortunately, the technology is not mature enough for mainline, given the variety of traffic, such as freight and local trains as well as expresses. It's part of the European Rail Traffic Management System (ERTMS) Level 3 specification for future installation in the European Train Control System (ETCS), which will feature moving blocks.Up to date, ERTMS/ETCS Level 3 Hybrid is the most mature and is developed using existing technology solutions augmented for optimisation

What's Next? Train to Train communication

You may have asked yourself, "What's beyond? What are the improvements that could happen?".

In 2016, a paper titled "ERTMS Level 4, Train Convoys or Virtual Coupling" was published in IRSE NEWS February 2016, and reissued in May of the same year in the Rail Engineer Magazine.

The latter was informally mentioned to be Virtual coupling that enables vehicle-to-vehicle communication allowing a very short headway. where the first train ('lead train') sends speed and braking curve data to the two other trains ('following train') creating a 'train convoy'. In other words, a sort of platooning.

Concept of Virtual Coupling

A combination of technologies to enable digital automated train operation: moving block, virtual coupling, advanced interlocking, TMS, and ATO.

Rail Baltica Signalling & Control Command Contract Awarded

2022-01-19T08:18:00.001-08:00

On January 17, 2022, an agreement was signed between the joint venture Rail Baltica, the overall coordinator of the project RB Rail AS and an international consortium for the engineering and project management of the Control Command and Signalling works for Rail Baltica.

A consortium led by mobility specialist Systra and made up of the railway branch of Egis and the Italian Italferr won a contract on January 17 to provide engineering and project management services for the preparation, procurement, and supervision of the deployment of the control command and Signalling subsystem for the Rail Baltica high-speed line.

the project company RB Rail AS judged Systra's bid to be the most advantageous in terms of price (563,065 euros) compared to the three other bids, which came from a Franco-Lithuanian consortium led by Egis Rail, from DB Engineering & Consulting, and from another German firm, Gauff Rail Engineering.

Supported by Estonia, Latvia and Lithuania, through the joint venture Rail Baltica and the overall project coordinator RB Rail AS, the double-track High-Speed Rail project equipped with the European Rail Traffic Management System concerns a line of some 870 km. A route that is to connect Tallinn to the border between Lithuania and Poland, via Pärnu, Riga, Panevėžys, and Kaunas, with a running speed of 250 km/h.

This dedicated passenger and freight line will be interoperable with the rest of the continent's trans-European transport network and competitive with other transport modes. It will be connected to 7 international passenger railway stations, 3 multimodal terminals, airports, seaports as well as several regional passenger stations, maintenance facilities, and interfaces with the existing 1520 mm rail network, the rail gauge still in use in the Baltic States.

China High-speed Train Network Miracle

2022-01-19T05:11:00.004-08:00

The operational mileage of China's high-speed railroads has exceeded 40,000 kilometers. China has by far the most extensive High-Speed Train Network in the world.

On December 30, 2021, the Anqing-Jiujiang section of the Beijing-Hong Kong high-speed railroad was put into operation and the high-speed railroad directly connecting Hefei to Nanchang was completed, with the fastest travel time reaching 2 hours and 22 minutes, marking the basic connection of the Shangqiu-Shenzhen section of the Beijing-Hong Kong Canal of the "eight horizontal and eight vertical" high-speed railway system.

To date, the operating mileage of China's high-speed railroads has exceeded 40,000 kilometers, which is equivalent to circling the earth's equator; the total mileage of China's operating railroads has exceeded 150,000 kilometers.

In 2008, the network included only one high-speed line, the one linking Beijing to Tianjin, which was put into service for the Olympic Games and covered a distance of 131 km in 30 minutes. In 2020, the network will cover more than 37,000 km and will link Hong Kong to Beijing or Shanghai, as well as Urumqi to Xian or Chengdu to Beijing.

Eurobalise, an integral part of the ERTMS

2021-12-24T06:44:00.001-08:00

Balises are an integral part of the ERTMS/ETCS ensuring the transmission of data between the trackside and the onboard unit. There are two types of balise according to the data to transmit: the 'Fixed Data Balise' that transmit the same information hence the use of the word 'Fixed' as the location of the train and 'Transparent Data Balise' connected to the 'Lineside Electronic Unit' and transmits data according to the aspect of the signal. Other words can be used to describe the two types as switchable, fill, and infill. The use of both types is used for ERTMS/ETCS Level 1 while for Level 2 and Level 3 mostly the first type is only used for the train location.

Eurobalise

Linking

As balises are installed along the track, linking is essential to ensure that a balise group has not been missed or not detected in addition to the assign the coordinate system for the group of balise that contains only one and to correct the data received from the odometer. Linking contains 5 information:

The identity of the linked balise group,
Where the location reference of the group has to be found.
The accuracy of this location
The direction with which the linked balise group will be passed over (nominal or reverse)
The reaction required if a data consistency problem occurs with the expected balise group.

Group of Balise

A group of balise has to have at least one balise and 8 as a maximum, each one must store at least the internal number illustrating its position in the group, the number of balises in the associated group in addition to the group identity.

Each balise group has its own coordinate system and its orientation, to know whether the reverse and nominal direction, is defined as 'Group Balise Orientation'.

For the group of balise created of 2 or more balises, the first one is called 'location reference' and gives the origin of the coordinate system of its group

Orientation of a 2 to 8-balise-group

For the single balise group (balise group composed of one balise), there are two scenarios according to ERTMS/ETCS Level. For level 1, the allocation of the coordinate system is done through the linking data and received from the previous balise group.

Orientation of a single balise group

For ERTMS/ETCS Level 2 and Level 3, LRBG (Last Relevant Balise Group) is used as a common location reference between the ERTMS/ETCS onboard and trackside equipments in those levels.

If the ERTMS/ETCS on-board equipment cannot evaluate the orientation of the last balise group detected, being a single balise group, i.e. no linking information is available to identify the orientation of the co-ordinate system of this single balise group, the ERTMS/ETCS on-board equipment shall report its position by means of a position report based on two balise groups reporting the train position in reference to the LRBG and the “previous LRBG”

Rules

Distance

Following the speed, the distance between two consecutive Standard Size Balises shall be:

2.6 m from center to center, on lines with a Maximum Permitted Speed of 180 km/h
3.0 m from center to center, on lines with a Maximum Permitted Speed of 300 km/h
5.0 m from center to center, on lines with a Maximum Permitted Speed of 500 km/h.

For Reduced Size Eurobalises, the same distances except a 2.3 m for a maximum speed of 180 km/h.

Minimum Distance Between Eurobalises

There are two sorts of distance that are not the same: the distance between two balise groups that is the closest balises of the two groups and the linking distance which is the distance between the first balise in each group.

Linking and Balise Group distance

Installation

The SUBSET-040 (Dimensioning and Engineering rules) describes some rules to take into consideration when installing balises:

The maximum distance between two consecutive balises within the same group shall be 12 m from reference mark to reference mark.

With regards to balises at a signal containing switched information any balise located in rear of the operational stopping location shall not be located further than 0.7m in rear of the operational stopping location.

Maximum distance between a balise and the stopping point

If the transition from one train detection section to the following one affects the information transmitted by a switchable balise, this switchable balise shall be placed at least 13.8 m in rear of the location where the detection device of the next section may start detecting the train.

Minimum distance between a balise of a balise group and limit of train detection section

Sources:

SUBSET-026-3: System Requirements Specification - Chapter 3 - Principles

SUBSET-023: Glossary of Terms and Abbreviations

SUBSET-040: Dimensioning and Engineering rules

SUBSET-036: FFFIS for Eurobalise

Automatic Train Operation - An Overview

2021-11-23T06:32:00.011-08:00

When it comes to Automatic Train Operation (ATO), the word 'Driverless' is often used and leads to the understanding that there is no attendant or driver in the train but this is not always true for many GoA (Grade Of Automation, explanation in the next chapter) that require the presence of a driver or an on-board staff.

ATO is a system that helps to automate trains, frequently used in metros as it's easier to ensure security and less used in mainlines that need more development to reach a higher level of automation and can be widely used as much as metros.

In the 60s were the first use of ATO in the United States of America (New York) and United Kingdom (London).

Grade of Automation (GoA)

GoA, as its name suggests, is the degree of the automation of a train depending on how much humans are evolved. The GoA is classified up to 4 levels as specified in The International Electrotechnical Commission (IEC) standard IEC 62290-1 and defined by the UITP (International Association of Public Transport):

Grade Of Automation Levels
Credit: UITP

GoA0: Manual operations with no Automatic Train Protection (ATP).

GoA1: Manual Operation with Automatic Train Protection.

GoA2: Semi-automatic train operation (STO); Train has ATO in addition to the ATP and it drives and brakes automatically with the presence of a driver in the cab that ensures some functions as closing the doors.

GoA3: Driverless train operation (DTO); Train equipped with ATO and ATP but with the presence of on-board staff.

GoA4: Unattended train operation (UTO); train operates fully automatically with no driver or attendant on it. For this GoA, control cabs are not required anymore in the rolling stock.

ATO & Metros

Automatic Metros - Statistics

According to a report about metro automation published in 2018 by UITP (International Association of Public Transport), in March 2018, automated metros reached the 1,000km milestone with the opening of the Pujiang Line in Shanghai. As of December 2018, nearly a quarter of the world’s metro systems have at least one fully automated line in operation.[]

by putting in service the Pujian Line in Shanghai, automated metros are operating 1 026 km around the world in 64 lines in 42 cities which represents an increase of more than a quarter -- or 27.7% -- compared to the 2016 World Report. The number of automated metro km worldwide is expected to triple by 2023, in particular in China, if the confirmed projects maintain their plans.

Cities with fully automated metro lines in operation, as of 31 December 2018
Source: UITP

Beyond 2023, forecasts based on confirmed projects show the number of automated metro km will preserve and will reach more than 3 800 km by 2028 whether by creating new lines or extending existing ones.

Forecasts of the evolution of the number of automatic metro km
Source: UITP

UITP makes it also possible to see an online map of the automated metros in the world through a website that created it.

CBTC for metro automation:

Most of the metros in the world are using CBTC (Communications-Based Train Control) system to achieve a GoA 4. How is this system works is shown in the video below:

ATO & Mainline

ATO for mainline isn't as developed as for metros with few examples around the world, in particular, in Europe that conducted and is conducting some projects to develop it more such as:

X2Rail-1 Start-up activities for Advanced Signalling and Automation Systems coordinated by Siemens Mobility

X2Rail-4: Advanced signalling and automation system - Completion of activities for enhanced automation systems, train integrity, traffic management evolution, and smart object controllers coordinated by Alstom.

The video above shows one of the joint development projects within the Shift2Rail development program to develop ATO over ETCS specifications:

ATO over ETCS architecture and specifications

For mainline, AoE (ATO over ETCS) is used following this architecture and specifications and is capable at this stage to reach GoA2.

ATO over ETCS Architecture
Credit: UNIFE

An animated picture was published by Siemens Mobility to show how it works:

ATO over ETCS
Credit: Siemens Mobility

ERTMS, what you need to know

2021-11-12T13:16:00.014-08:00

This article aims to give an overview of the European Rail Traffic Management System (ERTMS) through History, Statistics, European Deployment Plan, FRMCS, GSM-R alternatives, CCS TSI, Braking Curves, Baselines, Baselines compatibility, Levels, Modes, and case studies.

Definition and History
ERTMS Deployment statistics
ERTMS European Deployment Plan (EDP)
ERTMS Architecture, CCS TSI, and its interfaces
ERTMS Subsystems
FRMCS, The Successor of GSM-R
Is it possible to use other radio communication systems than GSM-R? ERTMS
Levels ERTMS Modes
ETCS Braking Curves
ERTMS/ETCS Baselines & Backwards/Forwards compatibility
The Elizabeth Line: one of the most challenging Signalling projects

For this article, you may need to refer to SUBSET-023, the Glossary of terms and abbreviations. (link: https://bit.ly/2Wc6dja )

1. Definition and History

The European Rail Traffic Management System (ERTMS) is a single European signalling and speed control system that ensures interoperability of the national railway systems, reducing the purchasing and maintenance costs of the signalling systems as well as increasing the speed of trains, the capacity of infrastructure and the level of safety in rail transport[1].

Before the ERTMS was conceived, almost every single country used to have its own Automatic Train Protection System (ATP).

European ATP systems

Normally these systems were not compatible with each other and thus crossing a signalling area border meant that trains needed to implement several on-board ATP devices, each of which was self-functioning. Due to the increasing international rail services, a harmonised ATP system is needed for the European context. Thus, the aim of the ERTMS was (and is) to gradually replace the different national ATP systems in European countries[2].

2. ERTMS Deployment statistics

According to the last update by UNISIG (Union Industry of Signalling), by September 2020, half of the ERTMS/ETCS Level 1 and Level 2 tracks are and 31% of contracted vehicles are outside Europe: these countries have also shown their taste and conviction for ERTMS deployment, committing to more than 12 000 vehicles and more than 30 000km of tracks. [3]

ERTMS worldwide statistics

ERTMS worldwide deployment evolution

3. ERTMS European Deployment Plan

The guidelines for the Trans-European Transport Networks (TEN-T) establish ERTMS as one of the requirements for railway infrastructure and sets out a deadline for its deployment on the core network by 2030 and on the entire network by 2050. Building on this, the ERTMS European Deployment Plan (EDP), adopted by the European Commission in January 2017, sets out deadlines for deploying ERTMS on some sections of the core network corridors for the period 2017-2023.

According to the Deployment Plan, the signalling system should be deployed on 15.682 kilometres of track by 2023. Of this target, 38 percent was realised in April 2020. The rollout of ETCS, the system on board of trains, is going slower than the installation on tracks. 12 percent of the core network corridors were in operation with the on-board system ETCS (6120 kilometres) and 63 percent with GSM-R, the system for railway communication that will be replaced by the newer system FRMCS[4].

4. ERTMS Architecture, CCS TSI, and its interfaces

Depending on the application level, the architecture of the ERTMS changes.

The picture below from SRS (System Requirements Specification) Chapter 2 (SUBSET-026) illustrates the mandatory applicable CCS TSI (Control Command & Signalling Technical Specification for Interoperability) and the ERTMS own interfaces.[5]

ERTMS/ETCS references architecture

(*) Depending on its functionality and the desired configuration, the national system can be addressed either via an STM using the standard interface or via another national solution.

Note: the entities inside the ERTMS/ETCS on-board equipment box are shown only to highlight the scope of the interfaces that are specified in the TSI CCS annex A.

Below, the list of specifications that figure in the picture. You can download them from here: https://bit.ly/3CZUaqh

CCS TSI Annex A – Mandatory specifications - Set of specifications 3 (ETCS B3 R2 GSM-R B1):

SUBSET-034: Train interface
ERA_ERTMS_015560: ETCS Driver Machine Interface
SUBSET-027: Juridical Recording
SUBSET-035: Specific Transmission Module FFFIS
SUBSET-056: STM FFFIS Safe time layer
SUBSET-057: STM FFFIS Safe link layer
SUBSET-058: FFFIS STM Application layer
SUBSET-101: Interface "K" Specification
SUBSET-100: Interface "G" Specification
SUBSET-036: FFFIS for Eurobalise
SUBSET-044: FFFIS for Euroloop
SUBSET-037: EuroRadio FIS A11T6001: (MORANE) Radio Transmission FFFIS for EuroRadio
SUBSET-047: Trackside-Trainborne FIS for Radio infill
SUBSET-114: KMC-ETCS Entity Off-line KM FIS
SUBSET-137: On-line Key Management FFFIS
SUBSET-038: Offline Key Management FIS
SUBSET-039: FIS for RBC/RBC handover
SUBSET-098: RBC-RBC Safe Communication Interface

In addition to the specifications above, there is also 'Informative specifications' that are available also for download: https://bit.ly/3mnvFNz

5. ERTMS Subsystems

Due to the nature of the required functions, the ERTMS/ETCS system will have to be partly on the trackside and partly on board the trains.

NOTE: Interlocking is not part of ERTMS

Trackside[5]

Depending on the application level, the trackside subsystem can be composed of:

Balise: is a transmission device that can send telegrams to the on-board subsystem
Lineside Electronic Unit (LEU) : The LEUs are electronic devices, that generate telegrams to be sent by balises, on basis of information received from external trackside systems.
Radio communication network (GSM-R): The GSM-R radio communication network is used for the bi-directional exchange of messages between on-board subsystems and RBC or radio infill units.
Radio Block Centre (RBC): is a computer-based system that elaborates messages to be sent to the train on basis of information received from external trackside systems and on basis of information exchanged with the on-board subsystems
Euroloop: The Euroloop subsystem operates on Level 1 lines, providing signalling information in advance as regard to the next main signal in the train running direction.
Radio infill unit: operates on Level 1 lines, providing signalling information in advance as regard to the next main signal in the train running direction.
Key Management Centre (KMC): The role of the KMC is to manage the cryptographic keys, which are used to secure the EURORADIO communications between the ERTMS/ETCS entities (ERTMS/ETCS on-board equipments, RBCs and RIUs)
Public Key Infrastructure (PKI): The role of the PKI is to manage and distribute digital certificates, so as to allow a secure on-line distribution of cryptographic keys between KMCs and from a KMC to the ERTMS/ETCS entities (ERTMS/ETCS on-board equipments, RBCs and RIUs).

Onboard[6]

Depending on the application level, the on-board subsystem can be composed of:

Euro Vital Computer (EVC): is the core of the ETCS onboard device. It is part of the Automatic Train Protection logic and is the unit with which all the other train functions interact, such as the odometer or the GSM-R data reception.
Driver Machine Interface (DMI): the interface between the driver and the ETCS. In most cases, it is an LCD touch screen panel for control and indication functions, allowing the driver to enter the required input data into the system and to visualise the output data.
Train Interface Unit (TIU): is the interface that allows the ETCS to exchange information and issue commands to the rolling stock.
Juridical Recording Unit (JRU): provides ‘black box’ functions, i.e. it stores the most important data and variables from train journeys, allowing later analysis.
Balise Transmission Module (BTM): The BTM is a module inside the ETCS onboard equipment for intermittent transmission from track to train, which processes signals received from the onboard antenna and retrieves data messages from a Eurobalise.
Loop Transmission Module (LTM): The LTM is an optional module inside the ETCS onboard equipment for transmission from track and train, which processes signals received from the onboard antenna and retrieves data messages from a Euroloop.
Onboard radio communication system (Euroradio): The GSM-R onboard radio system is used for the bi-directional exchange of messages between the onboard subsystem and RBC or radio infill unit. The onboard Euroradio is a module inside the ETCS onboard equipment for exchanging messages between track and train, which processes signals received from the onboard antenna and retrieves application data messages from the RBC or the RIU.
Odometry system: The odometer is responsible for calculating the distance run by the train, typically consisting of redundant tachometry and radar, able to calculate distance, speed and acceleration.
Specific Transmission Module (STM): The STM is a device that allows the ETCS onboard equipment to be interfaced with the onboard part of an existing National Train Control system. It will enable smooth transitions from/to the national system(s) and gives access to some ETCS onboard resources (e.g. DMI). Depending on its functionality and the desired configuration, the national system can be addressed either via an STM using the standard interface or via another national solution.

6. FRMCS, The Successor of GSM-R

GSM-R is approaching obsolescence. The GSM-R suppliers have committed to support this system until 2030, and possibly beyond. There is, consequently, a need to replace GSM-R, an issue which is critical in Europe where railways have implemented GSM-R on more than 100,000km of lines, in a fully interoperable way.
Since 2010, UIC-member railway organisations have been discussing a successor to GSM-R. The work on specifying the GSM-R successor, which is the Future Railway Mobile Communication Systems (FRMCS), was launched by the International Union of Railways (UIC) as a project in 2014[7].

FRMCS TSI

[8] FRMCS will be based on 3GPP building blocks, gaps will be covered by ETSI specifications. The system will have an FRS and an SRS, to provide the necessary means to operate the FRMCS networks and to guarantee their interoperability in the context of cross border operations. The FRS and the SRS will complete the FRMCS system and will be the base in the CCS TSI for the Train-Radio and ETCS critical applications. The UIC FRMCS planning includes three steps:

Deliver the first stable version of specifications and obtain frequencies
Prepare and deliver the FRMCS demonstrator, based on the stable specifications and 3GPP R16 products
Prepare and deliver a FRMCS European trial, based on updated specifications and 3GPP R17 products.

FRMCS Planning

7. Is it possible to use other radio communication systems than GSM-R?

Below are some cases where other radio communication systems like TETRA and LTE were used/going to be used:

Tetra

Australia: Siemens Mobility and DAMM Cellular Systems have together successfully implemented and tested an open and interoperable Tetra packet data solution which complies with the demands for ETCS Level 2. The tests were mainly focused on bandwidth requirements and the reliability of data delivery. They were performed according to UNISIG Subset-093 (PS version) – the communication requirement specification for ETCS describing the worst-case conditions for ETCS communication.[9]

Kazakhstan: National railway KTZ has certified the use of Bombardier Transportation (Recently acquired by Alstom) ETCS over a Teltronic Tetra voice and data communications network on the 300 km route from Zhetigen to Altynkol on the Chinese border.[10] The tests in the field demonstrated and it is recognized by KTZ, that the complete system solution, Integrated by TETRA NEBULA infrastructure and EN50155/EN45545 on board equipment, works stably on the whole back and forth track, under regular and high load traffic operation of signalling system, according to the requirements and specification.[11]

LTE

India: In January 2020, Alstom has won a contract worth €106 million from the National Capital Region Transport Corporation Ltd. (NCRTC) to design, supply and install the signalling, train control, and telecommunication system (Package 24) of the 82.15 km Delhi – Ghaziabad – Meerut Regional Rapid Transit System (RRTS) Corridor. This line will be the first in India to adopt the European Train Control System (ETCS) hybrid Level 3* signalling system, which is the core signalling and train control component of the European Rail Traffic Management System (ERTMS). The contract marks a world premiere for the combination of the latest ETCS standard supported by the latest digital Interlocking and Automatic Train Operation (ATO) over Long Term Evolution (LTE) radio. The integrated platform screen door solution will also provide utmost safety to passengers.

(*): Hybrid Level 3 is a combination of ETCS Level 2 with shorter virtual section normally used in ETCS Level 3 for even higher performance.[12]

8. ERTMS Levels[5]

ERTMS/ETCS Level 0

The train is equipped with ERTMS/ETCS operating on a line not equipped with any train control system (ERTMS/ETCS or national system) or on a line equipped with ERTMS/ETCS and/or national system(s) but operation under their supervision is currently not possible.

ERTMS/ETCS Level 0

ERTMS/ETCS Level NTC

The train is equipped with ERTMS/ETCS operating on a line equipped with a national system

ERTMS/ETCS Level NTC

ERTMS/ETCS Level 1

With or without infill transmission, train equipped with ERTMS/ETCS operating on a line equipped with Eurobalises and optionally Euroloop or Radio infill

ERTMS/ETCS Level 1

ERTMS/ETCS Level 2

The train is equipped with ERTMS/ETCS operating on a line controlled by a Radio Block Centre and equipped with Eurobalises and Euroradio, with train position and train integrity proving performed by the trackside.

ERTMS/ETCS Level 2

ERTMS/ETCS Level 3

Similar to level 2 but with train position and train integrity supervision based on information received from the train.

ERTMS/ETCS Level 3

9. ERTMS Modes

Operation modes can be defined as different conditions required for managing different situations regarding the status of the trackside and the train itself. Unlike the ETCS levels (associated with train-trackside communication), ETCS modes are related to the operational circumstances of the line or the onboard equipment status.[13]

ETCS modes

ISOLATION: In Isolation mode, the ERTMS/ETCS on-board equipment shall be physically isolated from the brakes and can be isolated from other on-board equipments/systems depending on the specific on-board implementation. Used in all levels: Level 0, level 1, level 2, level 3 and level NTC[14].
NO POWER: When the ERTMS/ETCS on-board equipment is not powered, the equipment is in the No Power mode. Used in all levels: Level 0, level 1, level 2, level 3 and level NTC.
SYSTEM FAILURE: The ERTMS/ETCS on-board equipment shall switch to the System Failure mode in case of a fault, which affects safety. Used in all levels: Level 0, level 1, level 2, level 3 and level NTC.
SLEEPING: The Sleeping mode is defined to manage the ERTMS/ETCS on-board equipment of a slave engine that is remote controlled. Used in all levels: Level 0, level 1, level 2, level 3 and level NTC
STAND BY: The Stand-By mode is a default mode and cannot be selected by the driver. Used in all levels: Level 0, level 1, level 2, level 3 and level NTC
SHUNTING: The purpose of the Shunting mode is to enable shunting movements. Used in level 0, NTC, 1, 2 and 3.
FULL SUPERVISION: The ERTMS/ETCS on-board equipment shall be in the Full Supervision mode when all train and track data, which is required for a complete supervision of the train, is available on board. Used in level 1, 2 and 3.
UNFITTED: The Unfitted mode is used to allow train movements in either; areas that are equipped neither with ERTMS/ETCS track-side equipment nor with national train control system or areas that are equipped with ERTMS/ETCS trackside equipment and/or national train control system(s), but operation under their supervision is currently not possible. Used in level 0.
STAFF RESPONSIBLE: The Staff Responsible mode allows the driver to move the train under his own responsibility in an ERTMS/ETCS equipped area. This mode is used when the system does not know the route. Used in level 1, 2 and 3.
ON SIGHT: The On Sight mode enables the train to enter into a track section that could be already occupied by another train, or obstructed by any kind of obstacle. This mode cannot be selected by the driver, but shall be entered automatically when commanded by trackside and all necessary conditions are fulfilled. Used in level 1, 2 and 3.
NON LEADING: The Non-Leading mode is defined to manage the ERTMS/ETCS on-board equipment of a slave engine that is NOT electrically coupled to the leading engine (and so, not remote controlled) but has its own driver. Used in all levels: Level 0, level 1, level 2, level 3 and level NTC.
National System (SN) mode: In SN mode, according to the specific on-board implementation, the National System may access the following resources via the ERTMS/ETCS on-board equipment: DMI, Juridical Recording interface, odometer, train interface and brakes. This can be achieved through the STM interface. Used in level NTC.
REVERSING: The Reversing mode allows the driver to change the direction of movement of the train and drive from the same cab, i.e. the train orientation remains unchanged. This is possible only in areas so marked by trackside. Used in level 1, 2, 3.
LIMITED SUPERVISION: The Limited Supervision mode enables the train to be operated in areas where trackside information can be supplied to realise background supervision of the train. Limited supervision can not be selected by the driver, but shall be entered automatically when commanded by trackside and all necessary conditions are fulfilled. Used in levels 1, 2 and 3.
PASSIVE SHUNTING: The Passive Shunting mode is defined to manage the ERTMS/ETCS on-board equipment of a slave engine (NOT remote controlled, but mechanically coupled to the leading engine), being part of a shunting consist. This mode can also be used to carry on a shunting movement with a single engine fitted with one on-board equipment and two cabs, when the driver has to change the driving cab. Used in all levels: Level 0, level 1, level 2, level 3 and level NTC.

10. ETCS Braking Curves[15]

A CCS system does not brake, i.e. it is not responsible for the braking system of the train, which will do the actual job. ETCS (and also some elaborated legacy CCS systems) supervises both the position and speed of the train to ensure they continuously remain within the allowed speed and distance limits, and -if necessary- it will command the intervention of the braking system to avoid any risk of the train exceeding those limits.

To do so the ETCS onboard computer must predict the decrease of the train speed in the future, from a mathematical model of the train braking dynamics and of the track characteristics ahead. This prediction of the speed decrease versus distance is called a braking curve.

The braking curve related to the speed decrease due to the emergency brake is called EBD (Emergency Brake Deceleration) curve. Each specific target location (corresponding either to a speed reduction or to a stop location) given by the ETCS trackside is used by the ETCS on-board to compute a fully deterministic EBD curve, which depends on both train and track characteristics. The shape of the EBD curve, for a given piece of track, will therefore vary according to the type of rolling stock: the less the emergency braking system is efficient, the flatter the EBD curve will be.

ETCS braking curve

The ETCS on-board calculates in real time other supervision limits: Indication (I), Permitted speed (P), Warning (W) and Service Brake Intervention (SBI) (only if the ETCS on-board is designed to command itself the service brake). They consist of locations that, when crossed by the train, will trigger some information to be given to the driver through appropriate graphics, colours and sounds on the Driver Machine Interface. These locations are defined in order to:

For the “I” supervision limit: leave the driver enough time to act on the service brake so that the train does not overpass the Permitted speed, when this latter will start to decrease. Without the indication it would not be possible for the driver to perform a transition from ceiling speed supervision to the target speed supervision without overpassing the Permitted speed
For the “P” supervision limit: in case of overspeed, to leave the driver an additional time to act on the service brake so that the train will not overpass the point beyond which ETCS will trigger the command of the brakes.
For the “W” supervision limit, to give an additional audible warning after the Permitted speed has been overpassed.
For the “SBI” supervision limit, to take into account the service brake build up time so that the EBI supervision limit is not reached after the command by ETCS of the full service brake effort. The SBI supervision limit is facultative and can be implemented on-board the train in order to avoid too frequent emergency braking, which can be damaging for both the rolling stock and the track.

11. ERTMS/ETCS Baselines & Backwards/Forwards compatibility

Baseline definition

The baseline is a stable kernel in terms of system functionality, performance and other non-functional characteristics. Any system needs to evolve, and new functions and corrections might be needed.
“Baseline 2’’ is the first set of requirements, considered as interoperable, and to be adopted at European level.
“Baseline 3” is a controlled evolution of Baseline 2 that includes new additional functions and backward compatibility with Baseline 2[16].

Backward and forward compatibility of ETCS baselines

A first baseline compatibility assessment undertaken by the sector (UNIFE/UNISIG and ERTMS Users Group) has checked the compatibility between ETCS baseline 3 MR1 and ETCS baseline 2 (release 230d).

Within the scope of this assessment and provided that its recommendations are taken into account, the ETCS baseline 3 MR1 is backward compatible with ETCS baseline 2.

A second baseline compatibility assessment has checked that:

ETCS baseline 3 R2 is fully backward/forward compatible with ETCS baseline 3 MR1.
Both the backward compatibility between ETCS baseline 3 R2 vehicles and ETCS Baseline 2 trackside and the compatibility between ETCS baseline 3 R2 trackside operated with system version X=1 (i.e. ETCS Baseline 3 R2 trackside using only baseline 2 functions) and ETCS baseline 2 vehicles.

ETCS baselines compatibility

The second baseline compatibility assessment also includes the analysis of the compatibility between trackside and onboard both within ETCS baseline 3 MR1 and within ETCS baseline 2, in the light of the problem description of the Change Requests included in ETCS baseline 3 R2.

This second baseline compatibility assessment confirms that the ETCS baseline 3 R2 is fully backwards and forwards compatible with the ETCS baseline 3 MR1, i.e. that ETCS baseline 3 R2 vehicles can run a normal service on ETCS baseline 3 MR1 trackside and ETCS baseline 3 MR1 vehicles can run a normal service on ETCS baseline 3 R2 trackside[1].

12. The Elizabeth Line: one of the most challenging Signalling projects

Crossrail is building the Elizabeth Line – a new railway in London that runs between Reading and Heathrow in the west to Shenfield in Essex and Abbey Wood in south east London. The new railway will use three distinct signaling systems, AWS/TPWS in the east, CBTC in the new central section and ETCS in the west.[17]

Elizabeth line Map and signalling systems

In addition to the different signalling systems, the control of the Crossrail route will be split across three control centres. On the GW main line, this is from the Thames Valley Signalling Centre at Didcot. The Crossrail core, including to Abbey Wood, will have a new control centre contained within Network Rail’s Rail Operating Centre (ROC) at Romford. The GE line, which is currently controlled from Liverpool Street IECC, will eventually transfer to the Romford ROC as well.

Elizabeth line - DMI

As can be imagined, testing such a complex signalling arrangement could never be progressed on site. The solution was to start with laboratory testing, involving several labs in different parts of the world including Bombardier in Stockholm and Delhi, Siemens in Paris, Braunschweig and Chippenham, Mors Smitt (part of Wabtec) in Crewe and Burton, Alstom for ETCS interoperability and a further lab for Customer Information integration.[18]

Elizabeth line - Onboard subsystem

Sources

[1] European Union Agency for Railways - European Rail Traffic Management System (ERTMS) Link: https://bit.ly/3z4DGdU

[2] European Commission - ERTMS - History of ERTMS Link: https://bit.ly/3B33Yhf

[3] UNISIG - Deployment Statistics Link: https://bit.ly/3CXw5jP

[4] Rail Tech - EU Commission: deployment ERTMS is behind on schedule Link: https://bit.ly/3klx6d4

[5] SUBSET-026-2: System Requirements Specification - Chapter 2 - Basic System Description Link: https://bit.ly/3CZUaqh (index 04)

[6] European Commission - Rail - Subsystems and Constituents of the ERTMS Link: https://bit.ly/2W9Wg6m

[7] Global Railway Review - FRMCS: More than just a successive replacement for GSM-R Link: https://bit.ly/3B2pens

[8] European Union Agency for Railways - FRMCS Definition, Specification and Standardization Activities Link: https://bit.ly/3AZVLKM

[9] TCCA - SIEMENS and DAMM complete testing of ETCS over Tetra Packet Data Link: https://bit.ly/381yjQO

[10] Railway Gazette Group - ETCS over Tetra certified Link: https://bit.ly/3zmRKQl

[11] Teltronic - Teltronic’s TETRA solution, certified to support ETCS Link: https://bit.ly/3sGVjhI

[12] Alstom - Press Release Link: https://bit.ly/3D88gG1

[13] European Commission - Rail - ETCS Levels and Modes Link: https://bit.ly/3z3QvVT

[14] SUBSET-026-4: System Requirements Specification - Chapter 4 - Modes and Transitions Link: https://bit.ly/3CZUaqh Index (04)

[15] ERA_ERTMS_040026 - INTRODUCTION TO ETCS BRAKING CURVES Link: https://bit.ly/3ml1JSo

[16] European Commission - Rail - ERTMS - FAQ on ERTMS Link: https://bit.ly/3mnUc5p

[17] ERTMS Solutions - ERTMSCAMCORDER TO BE USED ON AS AN INTEGRATED ONSITE TESTING SOLUTION ON THE CROSSRAIL PROJECT Link: https://bit.ly/3ze8GZ2

[18] Rail Engineer - Crossrail’s Signalling Challenge Link: https://bit.ly/3D0JCqG

Egypt, 3 contracts in 3 months

2021-11-09T14:10:00.004-08:00

Rolling stock contract for Phase 1 of Cairo Metro Line 4 - MC & Kinki Sharyo

Mitsubishi Corporation (MC), the prime contractor, and The Kinki Sharyo Co., Ltd. (Kinki Sharyo) announced yesterday 09 November that they have signed a contract worth approximately 40 billion Yen (355 million US dollars) with the National Authority for Tunnels (NAT) to deliver 184 cars of rolling stock for Phase 1 of Cairo Metro Line 4 (New CP 412).

Cairo Metro Line 4 Phase 1

Those trains will be delivered from 2025 to 2028. Cairo Metro Line 4 Phase 1 is approximately a 19-km line with 16 stations in total. It's expected that it would be open in 2028.

The above-mentioned contract is the third one since the announcement of Siemens Mobility of a historic contract for a High-Speed line last September and Alstom's largest metro rolling stock contract for Cairo's Metro Line 1.

Egypt's first High-Speed Line - Siemens Mobility

Last September, Siemens Mobility (SM) announced that it has signed a contract with NAT to design, install, commission, and maintain the first high-speed line in the country and the second one in Africa.

The contract consists of 660 km linking the port cities of Ain Sokhna on the Red Sea to Marsa Matrouh and Alexandria on the Mediterranean in addition to the rail infrastructures, trains, locomotives, and related services. SM will partner with Orascom Construction and The Arab Contractors for this project to complete all aspects of the project.

Cairo's - Alstom

Last Monday, an 876 million euro contract with NAT to deliver 55 9-car Metropolis trains in addition to an 8-year maintenance contract for the upgrade of the first-ever metro line in Africa and Egypt, Cairo Metro Line 1. These trains will be equipped with digital solutions like real-time passenger information, dynamic route maps, video displays, and video surveillance.

ERTMS Level 4

2021-11-07T07:32:00.005-08:00

More efficient Signalling Systems lead to increase capacity by reducing headway by trains and operating at a higher commercial speed on the same existing line. This is the case of the European Rail Traffic Management System (ERTMS) that the higher its level is, the higher the capacity will be.

Today, two of its 3 defined levels in CCS TSI (Control Command & Signalling - Technical Specifications of Interoperability), ERTMS/ETCS Level 1 and Level 2 who are based on fixed blocks are commercialised and deployed worldwide (Read ERTMS deployment statistics). Nevertheless, the moving-block-based solution, ERTMS/ETCS Level 3 is waiting for further development before it can be considered as a solution ready for deployment such as the above-mentioned 2 levels. To date, the most advanced and realistic type for this level is what's called "ERTMS/ETCS Hybrid Level 3" that is based on existing solutions, and its implantation is awaited in the latter half of the decade in, among other, France and India.

As you may have asked yourself, "What beyond ERTMS Level 3?". In 2016, a paper, "ERTMS Level 4, Train Convoys or Virtual Coupling" was published in IRSE NEWS February 2016, and reissued in May of the same year in the Rail Engineer Magazine.

Concept of ERTMS L4

According to the paper, this concept is described by its supporters under various names 'ERTMS Level 4', 'Train Convey', or 'Virtual Coupling'. The figure above shows the general concept.

The paper takes this concept through 3 questions:

Is the technology feasible?
Is it safe?
Does the concept create additional capacity?

Link to the paper:

China first monorail line

2021-11-04T14:23:00.007-07:00

On Wednesday, a first-time achievement in China was marked with the unveiling of the first monorail line in the country. Wuhu Rail Transit’s Line 1, located in the southeastern Anhui province, enters in service by riding one of Bombardier's (recently acquired by Alstom) 28 six-car Innovia monorail trains from Baimashan Station to the Baoshun Road station. The construction of this line started in 2017 with a total cost of approximately 1.25 billion US dollars. The townspeople were able to experience it even before putting it in service during trial tests last month.

Wuhu Monorail - Photo Credit: Alstom

The 30-km-line is equipped with an Automatic Train Operation (ATO) with the highest Grade of Automation (GoA), GoA 4 which means that is fully automated without any staff on board. This line contains 25 stations and operates at a speed of 80 km/h.

A brief history of monorail

Monorail is a rail-based transportation system based, as its name indicates, on a single rail that acts as its sole support in its guideway. Its idea belongs to Ivan Elmanov that dates back to 1820. Deptford Dockyard in South-East London is where the first-ever monorail was installed in the world in 1821. Since that, many monorail variants were experimented and proposed with but only a few projects were able to be built and to operate like Wuppertal Suspension Railway in Germany and Patiala State Monorail Train-ways in India.

Monorail came to public attention in the '50s when Disneyland Park in California and Walt Disney World in Florida and Seattle built the first monorails, the first to be installed in the USA.

Sources:

Alstom: https://www.alstom.com/press-releases-news/2021/11/chinas-first-fully-automated-and-driverless-elevated-monorail-provided

Train History: http://www.trainhistory.net/railway-history/monorail-history/

Disneyland: https://disneyland.disney.go.com/attractions/disneyland/disneyland-monorail/

ETCS language: Packets

2021-11-01T14:46:00.004-07:00

After talking and understanding in a precedent article the variables of ERTMS/ETCS language that this language is based on it in addition to packets, telegrams, and messages. Now, it's possible to talk about PACKETS as it's essential to understand variables to evoke it.

Definition of Packets

Packets are " Packets are multiple variables grouped into a single unit, with a defined internal structure." as defined in §7.3.3.1, chapter 7 of the System Requirements Specifications (SRS) 026.

So a good knowledge of variables, their structure, and rules is mandatory to understand packets.

Packets Structures

There are two structures of packets whether the information is transmitted from train to track or the opposite. Both of them start with a packet header (NID_PACKET) followed by:

For Track to Train transmission:

A unique packet number
Length of the packet in bits
The orientation information
Optionally:

The distance scale and
Information section containing a defined set of variables

Track to Train Packet Structure

For Track to Train transmission:

A unique packet number
Length of the packet in bits
Optionally:

The distance scale
Information section containing a defined set of variables

Train to Track Packet Structure

Lists of Packets

There are 55 packets for Track to Train transmission and 8 packs for Train to Track transmission. These two lists are defined in chapter 7 of the SRS 026. Each list figure in the picture below:

Track to Train Packets

Train To Track Packets

How to find and read a packet?

Each packet in the two pictures above is associated with a page number. The latter is where you can find the related packet in the SRS 026 - Chapter.

Example:

For packet number 5 (Linking) in the list of Track to Train, the page number associated is 15.

On page 15 of SRS 026 Chapter 7, packet number 5 (Linking) appear:

Find packet

To find out more about any variable on it, all variables are defined in §7.5 Definitions of Variables (as of page 44) in the same above-mentioned document:

Example:

Find variable

Source:

System Requirements Specification - Chapter 7 ERTMS/ETCS language

From GSM-R to FRMCS

2021-10-31T11:46:00.015-07:00

The technical specifications of Global System for Mobile Communications – Railway (GSM-R) were finalised approximately 20 years ago. At that time, negotiations were launched by the International Union of Railways (UIC) with the European Frequency Committee (CEPT) on whether to use TETRA or GSM. After choosing the latter, the UIC launched again with European Commission (EC) and railways a project called European Integrated Radio Enhanced NEtwork (EIRENE) that specifies today the requirements for mobile networks for railways. The European Telecommunications Standards Institute (ETSI) as a specialized of GSM were also involved.

Simplified GSM-R System, Source: UIC

A project called MObile radio for RAilway Networks in Europe (MORANE) to develop prototypes that have been tested in Italy, France, and Germany came after EIRENE to finalize it by the development of detailed specifications.

ERTMS/ETCS wouldn't be created without EIRENE and MORANE projects, following these two projects, it was launched as a project.

As technology advances, industrial will not support GSM-R as of the next decade. From here, the need for new radio communication system appears. A new project was launched for the successor of the GSM-R, called Future Railway Mobile Communication System (FRMCS). Below, a video by UIC that introduces this system.

For this project, besides UIC, the European Rail Industry Association (UNIFE), European railway infrastructure managers, and European suppliers are involved.

As it will not be easy to migrate completely from one system to another, we will have probably an approximate 10-year migration phase as of 2030 so there will be parallel use of both radio communication systems. Europe is well prepared for this phase and a decision to define the frequency bands of each system during this phase appeared in the Official Journal of the European Union on 30 September 2021:

COMMISSION IMPLEMENTING DECISION (EU) 2021/1730 of 28 September 2021

Article 1: This Decision establishes the harmonised conditions for the availability and efficient use of radio spectrum for the Railway Mobile Radio (RMR) in the bands 874,4-880,0 MHz, 919,4-925,0 MHz and 1 900-1 910 MHz..

Source:

https://uic.org/rail-system/gsm-r/

https://uic.org/rail-system/frmcs/

ERTMS deployment statistics

2021-10-29T08:12:00.166-07:00

European Rail Traffic Management System marks its presence inside but also outside Europe. It can appear in other names like CTCS in China and KTCS in South Korea. According to the last update in the last few months of UNISIG, a recognised stakeholder composed of nine UNIFE members: 50% of the contracted track (trackside) and 31% of the contracted vehicles (Onboard) in the world are outside Europe.

Worldwide ERTMS Trackside & onboard Contracts

Evolution of the ERTMS deployment

The right histogram below shows that ERTMS' onboard contracts worldwide has increased consistently in the last decade starting at around 4 297 vehicles in 2010 vehicles and reaching 12 124 vehicles by 2020 which represents a growth rate of 282%

ERTMS Trackside & Onboard Worlwide Contracts 2010-2020

For the ERTMS' trackside contracts (left histogram), it has almost the same growth rate 287% in the same period. Contracts awarded for the trackside part increased during the 10-year period from 11 334 km to 32 562 Km.

Statistics inside Europe

For trackside contracts (left histogram), Belgium took first place with 7 860 Km followed respectively by France 7 474 Km, Spain 7 302 Km, Poland 4 965 Km, and Norway 4 418 Km.

ERTMS Trackside & Onboard Contracts in Europe

For Onboard contracts (right histogram), it's Germany who leads the top 5 with 2 753 Vehicles before the United Kingdom with 2 447 Vehicles, Switzerland 1 491 Vehicles, Spain 1 054 Vehicles, and Belgium 5th with 1 021 Vehicles.

Statistics outside Europe

The country that has the most contracts for trackside equipped and/or will be equipped with ERTMS in the world is a country outside Europe, China, with more than 20 000 Km of tracks under ERTMS/ETCS Level 1 and Level 2 (equivalent CTCS level to ETCS). Turkey takes second place with 20 870 km followed by Saudi Arabia 4 519 km, Australia 4 221 km, and Algeria 2 515 km.

ERTMS Trackside & Onboard Contracts outside Europe

When it comes to onboard contracts, China is leading again with 2 096 vehicles then comes Saudia Arabia and Taiwan with 940 vehicles, Australia 780, and South Africa 600 vehicles.

Abbreviations:

CTCS: China Train Control System

KTCS: Korea Train Control System

UNISIG: UNion Industry of SIGnalling

UNIFE: Union des Industries Ferroviaires Européennes (The European Rail Supply Industry Association)

Source:

UNISIG: https://www.ertms.net/facts-figures/deployment-statistics/

GSM-R Alternatives for ERTMS

2021-10-28T05:36:00.014-07:00

GSM-R (Global System for Mobile Communications – Railway), the radio communication system mainly used for the implementation of the ERTMS.It is specified in both the TSI CCS and EIRENE (abbreviations below).

Is it possible to use other radio communication systems than GSM-R for ERTMS?

ERTMS Communication
Photo Credit: Comtest Wireless

Previous and ongoing experiences around the world show that it is possible to use other radio communication systems like TETRA (Terrestrial Trunked Radio) and LTE (Long-Term Evolution) with ETCS if they can fulfil the above-mentioned specifications.

Australia (TETRA)

Siemens Mobility and DAMM worked in an ERTMS/ETCS Level 2 project in Australia. For this project, they used TETRA Packet Data with ETCS to ensure communications between subsystems [1].

To approve this solution, after its implementation, they tested it according to specifications that specify the worst-case conditions for ETCS communication. Tests were approved.

Kazakhstan (TETRA)

Using the same radio communication system as the previous example (TETRA), Bombardier Transportation (recently acquired by Alstom) and Teltronic carried out together an implementation of the ERTMS using other radio communication system than GSM-R for the company Kazakhstan Temir Zholy (KTZ), the rail operator for passenger and freight [2].

Tests showed a stable function according to the requirements and specifications.

The project is a 300-km-line and the solution was recognized by KTZ.

India (LTE)

In January 2021, Alstom announced the winning of a Signalling & Telecom system contract in India. The particularity of this contract is that a solution for a communication system based on LTE will be deployed. Furthermore, this project represents the first Indian line that will use ERTMS/ETCS L3 Hybrid.

Abbreviations:

ERTMS: European Rail Traffic Management System

TSI CCS: Technical Specifications for Interoperability Control Command & Signalling

EIRENE: European Integrated Radio Enhanced NEtwork

Sources:

[1] https://tcca.info/siemens-and-damm-complete-testing-of-etcs-over-tetra-packet-data/

[2] https://www.teltronic.es/en/teltronics-tetra-solution-certified-to-support-etcs/

[3] https://www.alstom.com/press-releases-news/2021/1/alstom-wins-major-signalling-telecommunication-systems-contract-rapid

ETCS language: variables

2021-10-27T13:39:00.035-07:00

The ERTMS/ETCS has its own language to transmit information (to balises, radios, ...). The latter is based on variables, packets, messages, and telegrams [1]. For this article, we will focus on variables. What are they? In which form do they have to be (rules)? And which organizations are responsible for their assignment?

Definition of variables

Variables are what are used by ERTMS/ETCS to encode single data values. Variables cannot be split in minor units. The whole variable has one type. To create them, there are some rules that should be taken into consideration. The rules are described in the next part.

Illustration of the functioning of ETCS Level 2
Photo Credit: François Melchior

Rules

Rules in this section will be described in two parts: prefixes and other rules.

Prefixes

When it comes to variables, there is always at the beginning of each one, one of these prefixes according to the function/description:

Acceleration (A_)
Distance (D_)
Gradient (G_)
Length (L_)
Miscellaneous (M_)
Number (N_)
Class Number (NC_)
Identity Number (NID_)
Qualifier (Q_)
Time/Date (T_)
Speed (V_)
Text (X _)

Other rules

In addition to the prefixes, as mentioned above, there are other rules such as[2]:

Variables may have special values which are related to the basic meaning of the variable
Special values have always the highest values in a variable
Spare values are located between the normal and special values in the variable range
Names of variables are unique. A variable is used in context with the meaning as described in the variable definition. Variables with different meanings have different names.
When transmitting over the different transmission media, the most significant bit shall be transmitted first.
Boolean variables always use 0 for false and 1 for true.
All variable definitions are independent of the transport media over which they are used, if used in more than one media.

Definitions of various variables are available in chapter 7 of the System Requirements Specifications (SRS) 026 (page 44 to page 87).

Responsible organizations

There are two organizations responsible for assigning value depending on the coordination:

ERA: for variables that need international coordination,
Member States: for variables that need national coordination

The table below shows for each variable the related responsible organization for assignment:

Variables and Responsible Assignment organizations

ERA: NID_CTRACTION, NIC_C, NID_ENGINE, NID_NTC, and NID_XUSER
Member States: NID_BG, NID_LOOP, NID_RBC, NID_RIU, NID_MN, NID_RADIO, and NID_KMC

How to request an assignment of values?

For the variables for which ERA is responsible for their assignment, a request form (link below) must be filled then sent to the email address request.etcs_variables@era.europa.eu

The request form contains 3 parts:

Date of submission.
Information about the submitter.
Information about the request.

Link: https://www.era.europa.eu/sites/default/files/activities/docs/ertms_etcs_variables_form_en.doc

Rail K&N

P44 - Data used by applications outside the ERTMS system

Automatic Selective Door Operation (ASDO)

Automatic Train Operation - UK

Migration to ETCS

Speedo Meter Unit change

Railways Applications, Safety Integrity Level (SIL)

Evolution and beyond Railway Signals and Blocks

Fixed Block

Moving Block

What's Next? Train to Train communication

Rail Baltica Signalling & Control Command Contract Awarded

China High-speed Train Network Miracle

Eurobalise, an integral part of the ERTMS

Linking

Group of Balise

Rules

Distance

Installation

Automatic Train Operation - An Overview

Grade of Automation (GoA)

ATO & Metros

Automatic Metros - Statistics

CBTC for metro automation:

ATO & Mainline

ATO over ETCS architecture and specifications

ERTMS, what you need to know

Table of Contents

1. Definition and History

2. ERTMS Deployment statistics

3. ERTMS European Deployment Plan

4. ERTMS Architecture, CCS TSI, and its interfaces

5. ERTMS Subsystems

Trackside[5]

Onboard[6]

6. FRMCS, The Successor of GSM-R

7. Is it possible to use other radio communication systems than GSM-R?

Tetra

LTE

8. ERTMS Levels[5]

ERTMS/ETCS Level 0

ERTMS/ETCS Level NTC

ERTMS/ETCS Level 1

ERTMS/ETCS Level 2

ERTMS/ETCS Level 3

9. ERTMS Modes

10. ETCS Braking Curves[15]

11. ERTMS/ETCS Baselines & Backwards/Forwards compatibility

Baseline definition

Backward and forward compatibility of ETCS baselines

12. The Elizabeth Line: one of the most challenging Signalling projects

Egypt, 3 contracts in 3 months

Rolling stock contract for Phase 1 of Cairo Metro Line 4 - MC & Kinki Sharyo

Egypt's first High-Speed Line - Siemens Mobility

Cairo's - Alstom

ERTMS Level 4

China first monorail line

A brief history of monorail

ETCS language: Packets

Definition of Packets

Packets Structures

Lists of Packets

How to find and read a packet?

From GSM-R to FRMCS

ERTMS deployment statistics

Evolution of the ERTMS deployment

Statistics inside Europe

Statistics outside Europe

GSM-R Alternatives for ERTMS

Australia (TETRA)

Kazakhstan (TETRA)

India (LTE)

ETCS language: variables

Definition of variables

Rules

Prefixes

Other rules

Responsible organizations

How to request an assignment of values?