SDH Link

1. 1

2. 2

3. Transmission network consist of the following major transmission
technologies:
 Optical fiber communication link
 Microwave communication link
3
Transmission Network link

4. 4
Transmission Protocol
SDH (Synchronous Digital Hierarchy)
PDH ( Plesiochronus Digital Hierarchy)
Both optical fiber and microwave communication
link support PDH and SDH link

5. Overview of Synchronous Digital
Hierarchy (SDH) Transmission
Network
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6.  ---- It stands for Synchronous Digital Hierarchy
 ---- It is a transmission protocol
 ---- It defines frame structure, multiplexing method, digital rates
hierarchy and interface code pattern
 ---- It needs for a system to process increasing amounts of information
 ---- It is a new standard that allows mixing equipment from different
suppliers
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7. Channel capacity of SDH
SDH Bit rate E1
STM-1 155.520 Mbps 63
STM-4 622.08 Mbps 252
STM-16 2488.32 Mbps 1088
STM-64 9953.28Mbps 4032
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8. Overview of PDH ( Plesiochronus
Digital Hierarchy) Transmission
Network
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9.  ---- It stands for Plesiochronus Digital Hierarchy
 ---- It is a transmission protocol
 ---- It is a technology used in networks run in a state where different
parts of the network are nearly, but not quite perfectly, synchronized
 ----- It allows transmission of data streams that are nominally running
at the same rate, but allowing some variation on the speed around a
nominal rate
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10. Signal Bit rate Channel
E1 2.048 Mbps 30-31
E2 8.448 Mbps 120-124
E3 34.368 Mbps 480-496
E4 139.264 Mbps 1920-1984
Channel capacity of PDH
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11. Advantages of SDH over PDH
PDH
Electrical interfaces
--- Only regional standards.
PDH rate hierarchies for PDH:
European (2.048 Mb/s),
Japanese, North American (1.544
Mb/s).
Optical interfaces
--- No standards for optical line
equipments, manufacturers
develop at their will.
SDH
Electrical interfaces
--- Can be connected with
existing PDH signals.
Optical interfaces
--- Can be connected to multiple
vendors’ optical transmission
equipments. 11

12. PDH
• Weak Operation,
Administration &
Maintenance function.
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SDH
• Abundant overheads
bytes for operation,
administration and
maintenance
• About 5% of the total
bytes are being used

13. Low rate SDH to higher rate SDH
( STM-1→STM-4→STM-16→STM-64 )
4:1
STM-1
A
STM-1
B
STM-1
C
STM-1
D
A
B
D
C
B
A
D
C
B
A
…
STM-4
One Byte from
STM-1 B
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Figure 1:SDH Multiplexing

14. 14
 PDH : Asynchronous Multiplexing
 The location of low-rate signals in high-rate signals is neither regular nor
predictable
 Not suitable for huge-volume transmission
140 Mb/s
34 Mb/s 34 Mb/s
8 Mb/s 8 Mb/s
2 Mb/s
140 Mb/s
de-multiplexer
de-multiplexer
de-multiplexer multiplexer
multiplexer
multiplexer
level by level
Figure 2: PDH Multiplexing

15. Communication System Overview
Message
Source
Transmitter Transmission
Medium/Channel
Receiver
Message
Destination
Noise,
Interference,
Distortion
Information Capacity, C = B log2 (1+SNR)
Development trend: Increase the bandwidth
Move to higher frequency
Figure 3: Basic concept of transmission system
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16. 16
Indoor unit Indoor unit
STM-1
Optical Mux
STM-1
Optical Mux
63 E1
Add drop
Multiplexing
Add drop
Multiplexing
63 E1
Outdoor unit Outdoor unit
Out door unit
Out door unit
Point to Point
communication
Point to Point
communication
IF cableIF Cable
Wave guide
Wave guide
Figure 4: P to P SDH MW link

17. SDH Optical Communication link
Optical Communication: Deals with theory and applications of
light wave signals (of frequencies ~1014 Hz or STM-256)
Optical Communication:
Uses light as a
medium of
communication
Optoelectronics:
Deals with other
applications of light
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18. Overview of Optical Communication
Light Source: LASER or LED
Digital
Signal
Light
Source &
Modulator
Photo-
detector
Digital
Signal
Optical Fiber
Optical Fiber: one or more glass fibers, and optoelectronic
repeater or fiber amplifier
Detector: APD or PIN
Figure 5: Optical communication
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19. 19
Figure 6:Establishment STM-16 SDH link

20.  ---- To be newly connection Ramna to SBN for GMSC, MSC,, BSC,
MGW etc. HLR
 ---- It is requirements STM-16 (2.5 Gbps) SDH link.
 ---- For STM-16 link the only physical media is suitable is Single mode
optical fiber cable. Hence Single Mode G.652 fiber is selected between
those sites and has been installed
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21.  ---- Synchronous digital hierarchy (SDH) refer to a group of fiber-
optic transmission rates that can transport digital signals with
different capacities.
 ---- STM-16 SDH Multiplexer is cost-effective and compact STM-16
SDH multiplexer equipment designed to manage and derive
services from the optical core to access
 ---- Microwave SDH link does not support STM-16 (2.5 Gbps).
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22. Transmitter Receiver
Connector
Splice
Connector
Power
Distance
Receiver Sensitivity
Link Loss
Margin
Figure 7 : Optical loss budget
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23.  Just take the difference between transmitter power and receiver
sensitivity
 Example:
Tx =-20 dB Rx = -30 dB
 Link Margin = 10 dB
 The loss of the total cable system must not exceed the Link Margin
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24.  Typical Attenuation for Single mode fiber:
0.4 dB/km @ 1310 nm
 Typical Attenuation for connector
0.5 dB/connector @ 1310 nm
 Typical Attenuation for Splice
0.3 dB/Splice @ 1310 nm
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25.  SM @1310 nm; typical values
6 km length x 0.4 dB/km = 2.4 dB
4 connector pairs x 0.5 dB = 2.0 dB
4 splice (mechanical) x 0.3 dB = 1.2 dB
___________________________________________________
Total = 5.6 dB
Transmitter Receiver
Connector
Splice
Connector
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26.  ----Determining Cabinet Positions
 ---- Marking Installation Hole Positions
 ---- Installing Supports and Slide Rails
 ---- Adjusting Support Height
 ---- Fasten all bolts. Assembling Supports
and Slide Rails
 --- Installing Floor Holder Fixing Components
 --- Installing Insulation Plates
Figure 8: Mux cabinet
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27.  ----Optical mux installation inside the cabinet.
 ---- Insert the optical interfaces
(STM-16 S16.1 card) on the optics rack.
 ---- Insert the Processing interface (PQ1 card)
 ---- Insert the Tributary interface (D75S card)
 ----- Optical Cross-connects (OXCs)
processing board CXL16
 -----Digital Cross-connects (DXCs) board GXCSA
Figure 9: Optics 2500
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28.  --- Installing Insulation ODF rack
 ----Verities type of optical connector.
These are SC-FC , FC-FC, and LC-FC etc
optical I-connector/Adapter
 ---- Different types patch cord use in optical
fiber for termination ODF to optical equipment
 ----Optical patch cord connect between
ODF and Optical interfaces board.
Figure 10:ODF
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29.  ---- The trunk cables include 75Ω/120Ω E1
cables
 --- Electrical interface to connect
optical interfaces.
 ---- 63 E1 Digital distribution frame (DDF).
 ---- Coaxial cable connect between DDF and
Electrical interface.
Figure 11:DDF
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30.  ---- The labels are affixed to the DC cables
that provide power for the cabinets
 ---- the protection grounding cables, including
the –48V, PGND, and BGND cables
 --- The labels for DC power cables are affixed
to one side of the identification plates on cable ties
Figure 12:DC Power
(1) (2)
TO:
A01 -48V2
B08
TO:
B03 -48V2
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31.  ---- Splicing is the act of joining two optical
fibers end-to-end using heat
 ---- Termination between two optical adapter
 --- Each Splice loss 0.5 dBm
Figure 13:Splice Machine
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32.  ---- Optical fiber measurement equipment is
Time Domain Reflecto meter (OTDR)
 ---- Get actual optical fiber length 6.8 Km
from OTDR
6.8 Km length x -0.4 dBm/km = -2.72 dBm
4 connector pairs x -0.5 dBm = -2.0 dBm
6 splice (mechanical) x -0.4 dBm = -2.4 dBm
__________________________________________
Total = -7.12 dBm
Figure 14:OTDR
Figure 15:Optical power
measure
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33.  ---- Optical cross-connects (OXCs) CXL16
transmit power is -2 dBm
 ---- Get optical power meter receive -2.1 dBm ,
wave length 1310nm
 ---- When fiber through interface from Ramna
to SBN receive level is -12 dBm ,
wave length 1310 nm.
 ---- Ramna and SBN almost same receive level.
Figure 16:Interface power
measurement
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34.  ---- Ramna transmit power (TX)
and SBN receive power (RX)
is connected
 ----Ramna receive (RX) and
SBN transmit (TX) is connected
 ----Finally to be get Ramna receive
level is -16 dBm and SBN receive level is -17 dBm
 ---- Optical Mux threshold level is -26 dBm
 ----STM-16 link has been completed.
Figure 17:STM-16 link
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35.  ---- Starting the PC
 ---- Setting IP Address for a PC
 ---- Starting the T2000-LCT Server
 ---- Network Element Commissioning
 ---- Configuring NE Commissioning Data
 ---- Configuration NE name, Date and Time
 ---- Configuration Services to the NE for Commissioning
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36.  ---- Testing Fiber Connection
 ---- Testing connection of Cables to interfaces
 ---- Testing Optical Fiber Jumper Connection
 ---- Testing Specifications of Optical Interfaces
 ---- Testing Received Optical power of an optical interface Board
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37. 37
Figure 18: UAT for Ramna to SBN

38.  ---- Management Function by LCT.
 ---- Order wire Phone Test
 ---- Power Supply Environment Test
 ---- Optical Power Test
 ---- Bit Error Rate Test
 ---- ON/OFF Test.
 ---- alarms (Critical, Major and Minor etc.).
 ---- Check of BOQ.
 ---- Visual checking of interconnection cables.
 ---- Checking of Overall Installation.
 ---- Checking of Physical Connection of Power.
 ---- Continuity test of each & every E1 between the stations.
 ---- Cable runs.
 ---- DDF and DDF cabling.
 ---- of Physical Connection of Earthling of the equipments
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39.  ---- STM-16 SDH link has been completed from Ramna to SBN
 ---- Optical Cross connects (OXCs) and Digital cross-connects
(DXCs) are to be completed
 ---- Both site Ramna and SBN optical receive level are correct
 ---- Optical receive level were some problem, when optical to be
installed
 ---- Get difference between optical fiber link budget loss and
calculating optical measurement loss
 ---- Finally STM-16 (2.5 Gbps) SDH link is ok.
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40. Thank you
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