PRESENTATION ON:SIGNALLING AND TELECOMMUNICATION IN
INDIAN RAILWAYS
PRESENTED BY: LOKESH GOGIABRANCH: EIC
YMCA University of Science and Technology
Faridabad-121006
Successful Organization
Innovative & Creativeactivities
Tight Control of Certain Routine Aspects
Organizational Imperative
Types of Organizations - Indian Railways Annual revenue of Rs 600 Billion Type I organizations
more than 100 years old well suited to deliver large scale repetitive tasks
Type II organizations Production units - 20 to 50 years old. Structured as production facilities
Type III organizations Commercially oriented Public sector companies -30 years old.
Type IV Organizations New PSUs created in last five years.
Type V organizations Type III PSU diversification and growth - “New” organizations of
seventies have matured and are setting up new ventures.
Type III and V Organizations
RITES, IRCON, CONCOR
The “new” ventures of the “seventies” are working together in new areas and markets.
About Company RITES Ltd. was established in 1974, under the aegis of
INDIAN RAILWAYS. It is an ISO 9001-2000 company and is a multi-
disciplinary consultancy organization in the fields of transport, infrastructure and related technologies.
Multidisciplinary internationally recognized consultancy organization in the field of transportation infrastructure - “Mini-Ratna” company
Provides consultancy and engineering services in the fields of railways, urban transport, urban development and urban engineering, roads and highways, airports, ropeways, inland waterways, ports and harbor, information technology, signal and telecom and export packages of rolling stock and railway related equipment.
Signal and Telecom services provided:-o
Field survey and collection of Data Feasibility studies
System planning and design System specifications
Detailed engineering Project Management
Tender documentation Bid invitation and evaluation
Contract negotiations Project preparation and planning
Installation and supervision Acceptance testing and commissioning
Maintenance methodology Training of client's personnel
Signals and telecom projects (ongoing and completed)
SIGNALS IN RAILWAYS
Signals in Railways Medium to convey pre determined meaning in non- verbal form which
convey definite informationRequirements of signals: For safety purpose. For efficient running of train. Control movement. Safe and reliable communication. Reduce traffic.
Types of signalsSemaphore Signals(mechanically)Colour light signals
SEMAPHORE SIGNALS
Consist of a vertical post on which a movable arm is pivoted at the top.
For indicating signal at night arm is fitted with two lenses, duplicating the indication displayed.
Lenses are illuminated from behind, originally by oil lamps, later by electric lamps.
Arm of the signal is displayed in a horizontal position to show the “stop” or “danger” indication. The red lens is illuminated.
To give a “ proceed” indication, the semaphore arm is raised to an angle of 45 degree. Movt. Of arm causes green lens to replace red.
Movable arm is controlled by means of levers and cables from the cabin.
These are fixed on the left hand side of track, with spectacles towards driver.
Colour light signals Used for automatic signalling these days No moving arm is present Give indication by electric light both during day and night
o Red – Stopo Green – Proceedo Yellow – Proceed with caution
RECEPTION SIGNALS
Outer signals This is the warner signal first seen by the driver Trains moving at high speed require certain distance for stopping Hence driver informed about the position in advance that platform
is clear or not. This signal gives the position of stop signal ahead. As it is provided at some distance away from station it is also called
as distant or outer or warner signal. In horizontal or stop position it indicates that the driver must bring his train to halt within 90 m before outer signal and than proceed to the home signal with caution
Home signal or Stop signal It is next signal after outer signal towards station It is a simple semaphore signal and indicates whether platform is clear
or notAfter the outer signal towards station is a stop signal and exactly placed at the station limit is called home or stop signal. Its main function is to protect the stations. The permission to enter the platform is given by the operation of this signal. The maximum unprotected distance between the signal and the point, it is intended to protect is specified as 180 m due to its location at the door of station, it is called home signal.
2-aspect colour light signal(left) Signal with red and green aspect is act as a replacement for a semaphore
stop or home signal. A 2-aspect distant signal would have yellow and green aspects. The white plate below the signal will display an identification plate using the
reference letters of controlling signal cabin and the signal number.
3- aspect colour light signal
Developed to allow higher speeds and shorter block section to accommodate more trains.
Three aspects are red, yellow and green. The red indicates stop, the yellow indicates that only one block section
ahead is clear and the next will be stop aspect and the green indicates that atleast two blocks ahead are clear.
DESPATCH SIGNALS
Starter Signal This signal is provided at the forward end of platform
and controls the movement of the train as they leave the station. It gives permission to the train to leave the platform for next station. No train can leave the platform unless this signal is lowered, that is why it is called starter signal. A separate signal is provided for each line.
Advance Starter Signal The limit of a station section lies between the home signal and
the advance starter signal. The signal which allows the train to enter in block section is called advance starter signal. It is always placed beyond the outer most set of the point connections. These signals are placed about 180m beyond the last point or switches.
Station Section
4-aspect colour light signal Normal aspect of the signal is green. When train pass green signal but still in that block red aspect will indicate. The signal allows a single yellow to indicate one block ahead is clear. A double yellow to indicate two blocks ahead are clear. Green to show atleast three blocks ahead are clear.
Subsidiary Signals
To ensure safety To optimize the use of tracks & rolling stock, help movement inside
big yards, station premises. To give instruction to driver at stop signals regarding the condition of
track head
Types-I. Shunt SignalsII. Calling on signal
Shunting Signals Also called as disc or ground signals or miniature semaphore signals Used during shunting operations Consist of a circular disc painted white with a red band along its
diameter. Red band is horizontal – stop Red band is inclined – proceed Similar to semaphore these are also provided with lamp and colored
glasses
They are placed below stop signal and are used for diverting routes without showing the particular route.
Modern shunt signal This is a typical modern shunt signal, used to allow movements into
and out of a siding. It has three lights with red and white indications. The signal can be seen at ground level or attached to a signal post
below a normal stop signal. The ON indication shows a red and white light side by side. The OFF indication shows two white lights at 45 degrees.
Calling on Signal It is small size signal placed below main stop signal It permits the driver to proceed till the next stop signal with caution
and be prepared to stop short of any obstruction. Signal is capable of being taken off only when the stop signal above it
is in ‘ON’ position & vice versa. These signal cannot be taken ‘OFF’ unless a train has come to a stop
at the signal.
Typical Train control room.,
DATA LOGGER It is a microprocessor(32 bit Motorola 68000
Microprocessor) based digital data storing system.
Record data over time or in relation to time or in relation to location either built in instrument or sensor via external instrument & sensors.
Has inbuilt temperature sensor. Its storage capacity is 1.7/35 lakh events. Data collected by data logger can be used for
failure analysis, repetitive discrepancies and accident investigations
They are provided in relay room of big yards to maintain the operation of signalling gears.
Electrial Point Machine It is an electrical driven machine used fo operation
of points in railway yards.
POINT MACHINE ( MOTOR DRIVEN DEVICE) It operates switches of track(points). In case of failure
of such a device delay to trains can be avoided by crank handling
Points are used to divert trains from one line to the other, and it will become a source of danger unless adequate precaution is taken.
The points should be correctly set i.e. the closed switch should be housed correctly against the stock rail and the open switch should be well clear of the corresponding stock rail
Toungue Rail on points Stock Rail points Check Rail points V Rail points Cross over WWN button on panel Point button at bottom left
Continue…
FM(FOULING MARK) Used to prevent side collision of two trains when they are traveling on
different tracks come on same track after certain time. To show that latter two tracks are coinciding to form single track. Signals are applied at 15km distance away from FM
COMMUNICATION IN RAILWAYS
Today’s Railway Communication Systems
Limitation and Consequences Not Interoperable
Limited applications Inefficient use of resources( radio freq., cabling….) High procurement cost ( several different systems, no big market for suppliers) High operational cost( power supply, leased line cost …) High maintenance cost ( service organization and logistics for each of the systems) Technical evolution almost impossible
WHAT IS GSM-R ? GSM-R stands for GSM(global system for mobile communication) for
railways. A communication system for railway networks utilizing GSM
technologies and specific applications for railway operations.
WHY IT IS NOW OPTED FOR RAILWAYS? To solve the maintenance costs, limited interoperability between
railway networks, the concept of GSM-R was introduced. To meet the evolving railway business challenges that are:
Iteroperability with national and international railway network’s communication systems.
Improved operational performance to achieve higher efficiency, safety, reliability, passenger satisfaction.
Differentiating value added services to increase customer loyality and explore other revenue sources
Frequencies used in GSM-R
GSM-R occupies a 1.6 MHz wide range of the P-GSM band (900 MHz-GSM) held by Indian Railways
Uplink: 907.8–909.4 MHz Downlink: 952.8–954.4 MHz
Basic feature of GSM-R
Full GSM system architecture
Basic structure of a standard PLMN(GSM) network architecture with its interfaces is shown in fig.
SSS is based on the worldwide most successful digital switching system EWSD.
All register function like VLR, HLR, EIR and GCR are realised as software implementation on EWSD-platform(Elektronicsches wahl system digital)
EWSD performs switching for over 160 million lines in more than 100 countries) it is developed by siemens
Typical GSM-R Network Structure Star Connection-
The BTS are connected to the BSC in star connection This connection applies especially for sectorised BTS with
several carriers Chain Connection-
The BTS are connected to the BSC in a chain connection via multidrop.
Whenever a BTS fails or thr link interface for the A-bis connection is defect, a relias switches the PCM30 through to the next BTS. The switchover will be seamless for the connection
Star Chain Connection- The BTS are connected to the BSC in a Star Chain connection
via multidrop. The first two BTS are connected chain, after BTS we split up
into star chain. The advantage is a better usage of existing railway
communication cables. Functionality in case of BTS or link failure is equal to the first
prescribed connection types.
Continue.. In these path always able connecting the BTS’s
Reliability of ether copper wire or fibre optic cable in combination with the necessary line termination ( NTPM, HDSL- modem or Drop in Drop out-multiplexer ) is not necessarily as high as the one of BTS and BSC, even a very high reliability of BTS will not improve availability of the system.
Therefore, railway applications with high requirements for reliability will make use of the multidrop loop architecture.
The interleaving of BTS of two different loops will decrease the consequences of a single BTS or BSC failure. Loop Multidrop connection:
Upto 7 BTS could be connected in one loop using one pcm30 for.
The risk of cable as critical path is reduced. Two interleaved BSC with Loop
Multidrop:• The BTS are connected to two different BSC in
Loop Multidrop interleaving eachother on a one by one scheme.
• In the prescribed case, both the risk of a cable failure and a BTS or BSC failure is reduced
The suggested case operates with a fully duplicate network structure with either collocated or staggered radio cells. To allow these two network ‘levels’ several functions like
• Priority of cell A1 or B1• Other hierarchical cell parameters• Subscriber administration• Load distribution
TCUBSC
DMS-MSC
VMS SMS EIR
HLR
NSS
IN
BTS
BTS
RSM
OSS
TerminalsDispatcher
Dispatcher
PABXCopyright © 1996 Northern Telecom
PABXPCU / SGSN
GGSN
DataIWF
OMC-D
OMC-S
OMC-R
Transmissionsolutions
GSM –R INFRASTRUCTURE
DETAILS OF THE GSM-R FUNCTIONS
FUNCTIONS GSM-R
Functional addressing
Location dependent addressing
Access matrix
Functional number
A term used to describe the process of addressing a call using a number representing the function a user is performing, rather than a number identifying the user’s terminal equipment.
The full number used within the functional addressing scheme to identify an end user/system by function or role.
The access matrix defines which subscribers are able to contact which other subscribers within the EIRENE network.
Location dependent addressing is provided to route calls for a given function to a destination number that is dependent upon the user's location.
Confirmation of Railway
emergency calls
Emergency calls by mobiles is confirmed by a message sent to a ground-based central location.
OPERATIONAL ASPECTS
EMLPP
VBS
VGCS
Enhanced Multi-Level Precedence and Pre-emption.
Voice Broadcast Service.
Voice Group Call Service.
TELECOMSERVICES
MOBILE
DISPATCHER
Copyright © 1996 Northern Telecom
VBS and VGCS: Group Calls
GSM-RNETWORK
The Voice Broadcast Services (VBS) and the Voice Group Call Services (VGCS) permit the distribution of a voice call from:
- users- dispatchers
to a user group located in defined geographical zone in the same way as a preset group of dispatchers
Voice Broadcast Service:A bidirectional channel is dedicated to the caller.A downlink unidirectional channel is dedicated to each cell of the calling zone (spectral efficiency)
Group call:As for VBS, a unidirectional channel is allocated in each cell of the calling zone (spectral efficiency)The caller uses the uplink link of the unidirectional downlink channel allocated in its cellThe speaker change is made with PTT (Push To Talk)
eMLPPGuaranties the access to the network resources for the priority calls even in case of congestion
PRECEDENCE Priority allocation during call setting and for hand-overs
PRE-EMPTIONIn case of resources lack, requisition of the resources used by a lower priority call
THE SUPPLEMENTARY SERVICE EMLPP APPLIES TO Point to point voice and data callsBroadcast voice callsGroup voice call
Priority Levels
Call settlings classes
eMLPP
Pre-emptioncapability
Waiting lines
management
EMLPP: PrioritiesEnhanced multi-level precedence and pre-emption
The dispatcher calls a functional number in order to join the driver of a specific trainController
GMSC
HLRm
IMSI MSISDN
MSC/VLR
Copyright © 1996 Northern Telecom
Functional #CFU MSISDN
Functional HLR
Train driver functional number sending
Functional Addressing
FUNCTIONAL ADDRESSING ; The functional addressing permits to call a user or an application via a number which identifies its function (instead of its MSISDN)
THE FUNCTION « FOLLOW-ME » of the GSM is used to:
Registration, deregistration and interrogation of the functional numbers
FUNCTIONAL NUMBERS
The presentation displays an information according to :
The functional number of the recipient for the caller,
And the functional number of the caller for the recipient
The functional number is carried by the end-to-end supplementary service UUS1
Dispatcher (CFN = 765432)
Copyright © 1996 Northern Telecom
ExternalNetwork or
PABX
Dispatcher 765432
Train driver 234567
Train Driver234567
Train Driver (TFN = 234567)
GSMAccess
Functional Number Presentation
UIC Priority priority Pre-emption
Railway Emergency 0 1 and lower
Control-command (ETCS) 1 2 and lower
Emergency public calls 2 3 and lower
Railway Operations
(radio ground-train,...)3 4 and lower
Railway information and other calls 4 -
Data calls ETCS
Priority Calls
Every calls use the eMLPP service
Group call