By Kovid KaushikRoll-ece 087

acknowledgementsacknowledgements

• my sincere thanks to my sincere thanks to Mr.ALOK RANJAN, Mr.ALOK RANJAN, DSTE-TELEDSTE-TELE. I pay special thanks to . I pay special thanks to Mr. Mr. Sudheer Chawla, Mr. Krishna Avatar, Sudheer Chawla, Mr. Krishna Avatar, Ms Anisha Modak, Mrs. Jyotsana Mr. Ms Anisha Modak, Mrs. Jyotsana Mr. Sumer Singh, Mr Banty Kr SaoSumer Singh, Mr Banty Kr Sao, who in , who in spite of their busy schedule have lent spite of their busy schedule have lent their precious time for helping out me their precious time for helping out me to understand various systems used in to understand various systems used in DMRC .DMRC .

Need Need

• Delhi has more registered vehicle than the Delhi has more registered vehicle than the total number of vehicles in Mumbai, total number of vehicles in Mumbai, Calcutta and Chennai put together. Calcutta and Chennai put together.

• Delhi has now become the fourth most Delhi has now become the fourth most polluted city in the world, polluted city in the world,

• Need to improve both the quality and Need to improve both the quality and availability of mass transport service. availability of mass transport service.

• Is possible only if a rail-based mass transit Is possible only if a rail-based mass transit system, system,

Delhi MRTS ProjectDelhi MRTS Project• a feasibility study for developing such a multi-a feasibility study for developing such a multi-

modal MRTS system was commissioned by modal MRTS system was commissioned by GNCTD (with support from GOI) in 1989 and GNCTD (with support from GOI) in 1989 and completed by RITES in 1991. completed by RITES in 1991.

• will cost approximately Rs 4860 crores will cost approximately Rs 4860 crores

• 11 km to underground (METRO) corridor along 11 km to underground (METRO) corridor along with 44.30 km of elevated / surface (RAIL) with 44.30 km of elevated / surface (RAIL)

• a joint venture company (viz., Delhi Metro Rail a joint venture company (viz., Delhi Metro Rail Corporation Ltd.) set up on 50:50 partnership Corporation Ltd.) set up on 50:50 partnership basis by GOI and GNCTD (within 10 years) basis by GOI and GNCTD (within 10 years)

Fiber Optics Transmission Fiber Optics Transmission System (FOTS) in DMRCSystem (FOTS) in DMRC

FOTS can be termed as the backbone FOTS can be termed as the backbone of DMRC telecommunications .Fiber of DMRC telecommunications .Fiber optical cables are on both sides of the optical cables are on both sides of the track.You can see as yellow The track.You can see as yellow The number of fibers is determined in number of fibers is determined in order to comply with redundancy. The order to comply with redundancy. The fiber is redundant for security and fiber is redundant for security and protection. In case of fiber optic protection. In case of fiber optic failure, communication can take place failure, communication can take place via spare fiber while the fiber that is via spare fiber while the fiber that is down may be fixed.down may be fixed.

The main components of the fiber optic transmition1. Optical fiber cables2. Synchronous Digital Hierarchy (SDH)3. Digital Distribution Frame (DDF)4. Flexible Multiplexer (FMX)5. Optical Distribution Frame (ODF)

Optical Fiber Cables Fiber cables are used for the transmission of the data from one station to the other station. An optical FIBRE has two concentric layers called the core(n1, refractive index =1.48 to 1.5) and the cladding (n2, refractive index=1.46 to 1.48). The refractive index of core is slightly higher than that of the cladding i.e. n1>n2. This difference between n1 and n2 allows total internal reflection. Light ray enters the FIBRE and strike core cladding surface at and angle greater than the critical angle. This is totally reflected back into the core. As angle of incidence and angle of reflection are equal the reflected light will again be reflected. The light will continue to travel in zigzag manner down the length of the FIBRE.

SYNCHRONIZED DIGITAL SYNCHRONIZED DIGITAL HIRARCHY (SDH)HIRARCHY (SDH)

In early 60’s the analog communication was taken In early 60’s the analog communication was taken over by the digital communication. There are number over by the digital communication. There are number of advantages of digital communication over analog of advantages of digital communication over analog system. With the advent of semi conductor circuits system. With the advent of semi conductor circuits and the increasing demand for the telephone and the increasing demand for the telephone capacity, a new type of transmission method called capacity, a new type of transmission method called Pulse Code Modulation (PCM) made an appearance. Pulse Code Modulation (PCM) made an appearance. It allows multiple use of a single line by means of It allows multiple use of a single line by means of digital time domain multiplexing. The analog digital time domain multiplexing. The analog telephone signal is sampled at a bandwidth of 300-telephone signal is sampled at a bandwidth of 300-3400Hz, quantized and encoded and then 3400Hz, quantized and encoded and then transmitted at a basic bit rate of 64Kbps.transmitted at a basic bit rate of 64Kbps.

• Audio range =4khz =4000hz• Sampling frequency =2*4000 =8000hz• No of bits / sample =8Bit rate =8000hz x 8 bits/sample =64 Kbps =.Further the bandwidth of speech signals andvisible range is limited.with the advancement in the needs of the frequency bands, this bandwidth must be utilized.

•So the frequencies must be multiplexed in order to transmit maximum information through the channel. •The multiplexing is achieved by time division multiplexing (TDM).•In TDM, the time axis divided into slots and more information can be transmitted. For an audio signal the time period of the signal is 0.025ms.•Time period of the sampled signal = 1/ 8000

=125 ms•This implies that between two samples there is gap of 125 ms. Between this time interval of 125 ms, we can multiplex number of signals.

• When 32 channels are multiplexed for a When 32 channels are multiplexed for a transmission rate of 2.048 Mbps speed transmission rate of 2.048 Mbps speed also E1also E1

• E2=4E1 E3=4E2=16E2 STM1= 63E1 E2=4E1 E3=4E2=16E2 STM1= 63E1

Access-MUX Access-MUX

• D D

PIDS (Passenger Information Display PIDS (Passenger Information Display System)System)

• There are 2 pids panel on each platform There are 2 pids panel on each platform plus 1on each side of concorse .plus 1on each side of concorse .

• It gives us direction and countdown ei. 4 It gives us direction and countdown ei. 4 means train is 4 stations behind .means train is 4 stations behind .

• Display panel consist of LEDs with Display panel consist of LEDs with matrix displaymatrix display

• Panel cards 1 LED card 2 Microprocessor Panel cards 1 LED card 2 Microprocessor card 3 LDR card card 3 LDR card

PAS( passenger addressing PAS( passenger addressing system) system)

• Pas broadcasting of voice messages Pas broadcasting of voice messages

• Exchanger net card –takes voice data Exchanger net card –takes voice data

• SA2(Serial Address) card –decides in SA2(Serial Address) card –decides in which zone should announcement be which zone should announcement be made .made .

OCC SERVER Zone 8M Shaper OCC SERVER Zone 8M Shaper Gatekeeper Amplifier SpeakerGatekeeper Amplifier Speaker

EBTS (Enhanced base EBTS (Enhanced base transceiver system)transceiver system)

• Remote site functionalityRemote site functionality

• Redundancy for fots (@128kbps)Redundancy for fots (@128kbps)

• DMRC uses motorola dimetra having DMRC uses motorola dimetra having benefit of TETRA standards range is benefit of TETRA standards range is 380-400MHz. 380-400MHz.

• Line Of Site usage 15 EBTS sites 25 Line Of Site usage 15 EBTS sites 25 to 75 miles apartto 75 miles apart

Breaker panel functions for power distributions Overload protection circuit breakers provides Manual on/off plus auto.Junction panel cabinet grounding ,inter-cablingCable terminationsCavity Combiner It combines TX and RX signalsSends them to APMReceiver Multi Coupler provides serial ports viareceiver in BR and combines them in TDM Environment Alarm system Analog power monitor measures incident and reflected power via vswr ranges from zero to infinity .Filter tray contains band pass filter

Tetra site Controller site controller provides the X.21 interface to master site and BR operations Can control 7BRs folowing are the components of TCS 1 Power PC mother board Site reference ISA card this uses GPS signal to provide time or frequency reference .X.21 interface card Ethernet LAN PCI card Flash memory cardBase Radio has 4channels

CLOCK SYSTEM CLOCK SYSTEM • Global Positioning System (GPS)Global Positioning System (GPS)

by Master Clock at OCC.by Master Clock at OCC.

• gps>> srs>>master clock gps>> srs>>master clock >>Lan>>submasterclock>>Lan>>submasterclock

LNA

PLGPS

TB

TB

TCPLTC

PL2QA

EPABX (Electronics Private EPABX (Electronics Private Automatic Branch Exchange)Automatic Branch Exchange)

• self-sustained telephone exchangeself-sustained telephone exchange

• EPABX System at OCC:EPABX System at OCC:

• Telephone system shall interface to the radio Telephone system shall interface to the radio system to enable radio users to initiate and system to enable radio users to initiate and receive calls to/ from EPABX extension or to receive calls to/ from EPABX extension or to MTNL or TATA INDICOM telephones. MTNL or TATA INDICOM telephones.

• Centralized Digital Recording System: The Centralized Digital Recording System: The telephone system is equipped with a CDRS for telephone system is equipped with a CDRS for recording of designed lines, emergency PAS recording of designed lines, emergency PAS announcements and designated conversion announcements and designated conversion system. system.

• Network Management System:Network Management System: The telephone The telephone network including EPABX system is monitorednetwork including EPABX system is monitored

Shelf 0 &Shelf 1Shelf 0 &Shelf 1 2 2 Power cardsPower cards: This card distributes power to : This card distributes power to

wholerackwholerack SF2X8 SF2X8 card: This card provides LAN ports for card: This card provides LAN ports for

monitoring of EPABX at other stations.monitoring of EPABX at other stations.• 2 2 DXCXL DXCXL cards: These are CPU cards used for cards: These are CPU cards used for

networking purposes.networking purposes.• ADPADP: Administrative Data Processor. This is : Administrative Data Processor. This is

also a CPU card performs controlling also a CPU card performs controlling information.information.

• HDMO cardHDMO card: Hard Disk Magneto Optical card : Hard Disk Magneto Optical card used for all software information backup.used for all software information backup.

Shelf 1Shelf 1• 2 2 SLMACSLMAC cards: This card is for analog cards: This card is for analog

phones. Maximum 24 phones can be phones. Maximum 24 phones can be connected to each card.connected to each card.

• 2 2 SLM02SLM02 cards: This card supports cards: This card supports digital phones. Maximum 24 phones can digital phones. Maximum 24 phones can be connected to each card be connected to each card

• LTUCA LTUCA card: This card connects shelf 1 card: This card connects shelf 1 and 0 in EPABX rack.and 0 in EPABX rack.

• 2 2 DIUN2DIUN2 cards: This card takes E1 cards: This card takes E1 signal from DDF. Links one station to signal from DDF. Links one station to other stations. There are 2 ports in each other stations. There are 2 ports in each card, one for analog and another for card, one for analog and another for digital. 2 cards for linking to both sides. digital. 2 cards for linking to both sides.

DDF

SDH

SDH

EPABX

DDF

EPABX

ODF

ODF

DDF-Digital Distribution FrameSDH-Synchronous Digital HierarchyODF-Optical distribution Frame

Station 1

Station 2

Station 2

conclusionconclusion

• Through this presentation I would Through this presentation I would conclude that in dmrc all the systems conclude that in dmrc all the systems are interdependent synchronization are interdependent synchronization is as important is as important

• Dmrc has compiled all the new Dmrc has compiled all the new technologytechnology

to make efficient company .to make efficient company .

Thank YouThank You