concept of pdh multiplexing
TRANSCRIPT
Concept of PDH Multiplexing
1
• What is the need of
• Exploiting the media and the line
terminal equipment for optimum
capacity.
•
2
•
Types of multiplexing ?
– FDM
– TDM PDH
3
– TDM
– DWDM
SDH
• What is Frequency Division Multiplexing ?
• Prescribed Structure of FDM?
Stage of No. of Chls Frequency Range
PDH MULTIPLEXING
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hierarchy
• Channel …… ……..1 1- 4 kHz
• Sub Group…………3 12 - 24 kHz
• Group…………….12 60 - 108 kHz
• Super Group………60 312-552khs
• Super Master Group……….900 Channel
(312-4028 Khz)
PDH MULTIPLEXING
5
(312-4028 Khz)
• Band for Microwave Radio Channel
2 x Super Master Group (900 Channel)
• Band for 4 Mhz coaxial cable 1 Super
Master Group (900 Channel)
• Band for 12 Mhz coaxial cable
PDH MULTIPLEXING
6
• Band for 12 Mhz coaxial cable
3 x Super Master Group (900 Channel) =
2700 Channel
• In TDM there are two type of
multiplexing
1. Plesiochronous Digital Hierarchy
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2. Synchronous Digital Hierarchy
• What is DWDM ?
– DWDM means on each wavelength we can
transmit one transport digital structure.
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transmit one transport digital structure.
• Prescribed PDH Hierarchies.
S. No. Order of Mux. Bit rates No. of Channels
PDH MULTIPLEXING
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1. First Order 2048kbit/s 30
2. Second Order 8448kbit/s 120
3. Third Order 34368kbit/s 480
4. Fourth Order 139264kbit/s 1920
5. Fifth Order 565Mbit/s 7680
PDH MULTIPLEXING
410 2 200 208 208 4 204
1a 2a 3a 4a 1b 2b 3b 4b
4 4
1b 2b 3b 4b s1 s2 s3 s4
8.448 Mbit/s ; frame length 848 bit: 100.4 us ; ITU-T G.742
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1 1 1 1 0 1 0 0 0 0 A N
1a 2a 3a 4a 1b 2b 3b 4b
A: Alarm Bit
N: National Spare Bit
: Stuffing Control Bit
S: Stuffing Bit
Frame sync signal
1 1 1 1 0 1 0 0 0 0 1 φ1 φ2 φ3 φ4x
y #2#1 #3
φ1 φ2 φ3 φ4 φ1 φ2 φ3 φ4
#49 #50
φ1 φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 1
C1
C11 C12 C13 C14
#51 #52 #53 #54 #55 #101 #102
φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 2
Details of 8.448 Mbit Frame Structure
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C11 C12 C13 C14 φ2 φ3 φ4 φ1 φ2 φ3 φ4
C2
C21 C22 C23 C24
#103 #104 #105 #106 #107 #153 #154
φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 3
C3
C31 C32 C33 C34
V #155 #156 #157 #158 #204 #205
φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 3
• Standard Principles of Multiplexing ?
• It conforms interfaces as per ITU recommendation G.703
• Principle characteristic of Multiplexing or De-multiplexing as per ITU
PDH MULTIPLEXING
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• Principle characteristic of Multiplexing or De-multiplexing as per ITU recommendation G.742
• Multiplexing method
bit by bit interleaving in tributary sequence
• Coding - HDB3
• Remote Station Alarm reception
• Local loop back
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• Local loop back
• Remote Loop Back
Elastic
Memory at
2Mbit/s
Elastic
Memory
at 8Mbit/s
ENCODER
Concept of Local Loop Back
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2Mbit/s at 8Mbit/s
DECODER
Concept of Remote Loop Back
Elastic
Memory at
2Mbit/s
Elastic
Memory
at 8Mbit/s
ENC.
Elastic
Memory at
2Mbit/s
Elastic
Memory
at 8Mbit/s
DEC.
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DEC. ENC.
A Station B Station
410 2 372 380 380 4 378
1b 2b 3b 4b
4
1c 2c 3c 4c s1 s2 s3 s4
34.368 Mbit/s ; frame length 1536 bit; 44.7 us; ITU-T G.751
4
1a 2a 3a 4a
16
1 1 1 1 0 1 0 0 0 0 A N
1b 2b 3b 4b
A: Alarm Bit
N: National Spare Bit
: Stuffing Control Bit
S: Stuffing Bit
1a 2a 3a 4a
Frame sync signal
1 1 1 1 0 1 0 0 0 0 1 φ1 φ2 φ3 φ4x
y #2#1 #3
φ1 φ2 φ3 φ4 φ1 φ2 φ3 φ4
#92 #93
φ1 φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 1
C1
C11 C12 C13 C14
#95 #96 #97 #98 #99 #184 #185
φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 2
Details of 34.368Mbit Frame Structure
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C11 C12 C13 C14 φ2 φ3 φ4 φ1 φ2 φ3 φ4
C2
C21 C22 C23 C24
#186 #187 #188 #189 #190 #281 #282
φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 3
C3
C31 C32 C33 C34
V #283 #284 #285 #286 #----- #-----
φ2 φ3 φ4 φ1 φ2 φ3 φ4SET 4
Plesiochronous Hierarchies -
Frame Structures
139.264 Mbit/s; frame length 2928 bit; ITU-T G.751
12 4 472 484 484 4 48444 4 484 4 480 4
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1 1 1 1 0 1 0 0 0 0 A N
1b 2b 3b 4b 1c 2c 3c 4c s1 s2 s3 s4
A: Alarm Bit
N: National Spare Bit
1a,b,c,d: Stuffing Control Bit
S: Stuffing Bit
1a 2a 3a 4a
N N
1b 2b 3b 4b 1b 2b 3b 4b
01
PARAMETERS BITS
ALLOCATION
SET
Frame alignment word : 111110100000
Alarm indication for far-end terminal
Bits reserved for national use
Bits coming from tributaries
from 1 to 12
13
from 14 to 16
from 17 to 488
Justification service bits
bits coming from tributaries
SET II to V
from 1 to 4
from 5 to 488
19
bits coming from tributaries from 5 to 488
SET VI
Justification service bits
Variable slots
bits coming from tributaries
from 1 to 4
from 5 to 8
from 9 to 488
Frame width
Bits per tributary per frame
Information bits per tributary
2928 bit
2928 : 4 = 732 bit
732 bit
• 2/8 Opti Mux.
• System Architecture as per (PUNCOM)
PDH MUXING
E
X
E
X2nd
2Mb/s 2Mb/sO/I O/I
20
X
C
H
A
N
G
E
2nd
Order
Mux/
Demux
8Mb
OLTE8Mb
OLTE
X
C
H
A
N
G
E
2nd
Order
Mux
2Mb/s
2Mb/s
2Mb/s
2Mb/s
2Mb/s
2Mb/s8Mb/s
O/W
8Mb/s
O/WPhone Phone
70 km (max)
2nd
Order
Mux/
Demux
Bit Rate : 8448kbps
Impedance : 75 Ohms
unbalanced
Line Code : HDB-3
Electrical Interface and Orderwire
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Type of Order Wire : ADM
VF Band : 0.3 to 3.4 kHz
S/NQ : >24dB
Noise : Better than
-45Bm0p
Optical Interface
Bit Rate : 8.976 Mb/s
Optical Source : Laser
Center Wavelength : 1310 nm
Spectral Width : 4nm or less
Mean Launch Optical
Power : -2 to -5dbm
PDH MUXING
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Power : -2 to -5dbm
Optical Receiver : PINFET
Receiver Sensitivity for : >-38dbm
BER 1 x 10E-10
Dynamic Range of Receiver : >20db
Receiver Overload : 0dbm
Type of Connector : FC - PC
• 2/34 Opti Mux.
• System Architecture as per (PUNCOM)
PDH MULTIPLEXING
E
X2/342Mb/sO/IE
X2Mb/s O/I
23
34Mb
OLTE
X
C
H
A
N
G
E
2/34
Mux
and
Dmux
2Mb/s
34Mb/s
O/WPhone
70 km (max)
X
C
H
A
N
G
E
2/34
Mux
and
Dmux
34Mb
OLTE
2Mb/s
34Mb/s
O/WPhone
(1)
(16)
(1)
(16)
34368kbit/s Interface (Specification as per HFCL make )
Bit Rate : 34368kbit/s
Impedance : 75 Ohms unbalanced
Tolerance : ±20ppm
Input Signal Code : HDB3
Out of Signal Code : HDB3
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Out of Signal Code : HDB3
Return Loss : >20 db in the 3.4 khz to 51 MHz band
Pulse peak Voltage : 1 Vpp ± 75Ω unbal.
Pulse width at half
Amplitude : 14.5ns ±2.45 ns
2/140 Opti-Mux. System Architecture
2/34
Mbit/s
2/34
Mbit/s
1
16
1
1634/140
Mbit/s
2/140
Mbit/sD
25
2/34
Mbit/s
2/34
Mbit/s
16
1
16
1
16
Mbit/s
Elect.
Interface Interface
Mbit/s
Optical
Interface
D
D
F
Specification as per Crompton - Greaves of
140Mbit/s Optical Interface
Bit Rate : 139.520Mbit/s
Line Code : CMI
Type of Laser : FP LASER
(Single-Mode)
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Wavelength : 1280 -1310 nm
Spectrum Width : ≤4nm
Mean launch optical : ≥-.5dBm(up to-
power 3dBm)
Contd...
Specification of Crompton – Greaves System
of 140Mbit/s Optical Interface
Receiver Sensitivity for : Better than -
BER 1x10 — 10 at 1310nm 32.0dBm
Connector : FC-PC
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Connector : FC-PC