CIS 267 - Business Telecommunications

1
???????
2
8. Multiplexing ??
DATA COMMUNICATIONS

• ????
• ????
• ????
• ????

3
??

• ???????????
• ??????,??????????
• ??????????????????????

4
?????????
5
8.1 ????

• FDM (Frequency Division Multiplexing)
• ??????????????????
• ??????????????
• ????????????(guard bands)
• ??,?????
• ??????????

6
??????
7
FDM ??????
8
??????
9
??????
10
???????
11
???????
???????????
12
?????ASK? FDM (1)
????
13
?????ASK? FDM(2)
?????
14
FDM??
15
????(WDM-Wave Division Multiplexing)

• ???????????????????
• ??????????????????
• ???????????
• ????????????????
• ??????????????
• ??????????

??
16
??????
17
?????????
18
DWDM?CWDM

• ??????( DWDM Dense Wavelength Division
  Multiplexing)
• ???OC48 (2.5 Gbps)?OC192 (10 Gbps)?????SONET??,?
  ?????40 Gbps????
• DWDM????????80??????OC48,???200
  Gbps?????????40???? OC192,???400 Gbps??????
• ??????(CWDM Coarse Wavelength Division
  Multiplexing)
• ?????DWDM?1/3,???????
• ??????CWDM?????????,??????8??????????16???,????100
  Mbps?2.5Gbps????????

19
CWDM?DWDN?????
20
OFDM?WDM??? - WDM????????? -
??OPDM,??????????????? - OFDM????????????,????
- WDM????
?????(OFDM)
21
FDM????
?????????FDM
22
FDM?????? (1)

• ??????????(CCIR) ???????
• 13???????
• CCIR-A?M?B?G?H?I?D?K?K1? L?N?C?E
• 3???????
• NTSC (National Television Systems
  Committee,??)
• PAL (Phase Alternation Line????,??)
• SECAM (SEqueniiaI Couleur Avec Memoire
  ????????????,??)
• ?????????
• HDTV?MAC?HD-MAC?
• ?????????????????
• NTSC?PAL??????????????,??????,????????????????,???
  ????????SECAM????-???,??????????????????????,?????
  ???????

23
FDM?????? (2)

• ??????????????????????????????????????????????????
  CCIR-M/NTSC?,??NTSC / M??
• CCIR-M????????(RF)???6MHz,???????4.2MHz,?????????4
  .5MHz???0.5 MHz(??)?????525?,??60Hz,??15.7 50KHz?
• ???????????????????????,????????????????????,NTSC?
  ?????????????????????,?????????????????????(??) ?
• NTSC????????????,????????????????,????????????????
  ?????,???????,?????????????????????

24
FDM?????? (3)
CCIR-M / NTSC??TV????
????

???
???? 52.5us
?????????
25
FDM?????? (4)
RF????(NTSC/M??)???
????fca
?????fcc
????fcv

fo
0.75MHz
1.25MHz
4.2MHz
4.799545MHz
5.75MHz
6MHz
26
FDM?????? (5)

• ??????????????CCIR-L/SECAM???????????CCIR-D/SECAM
  ?????????????????????CCIR-B/SECAM??
• ????60???????????????????PAL????????????????CCIR-D
  / PAL ?,??PAL/D?????????????????????????????????
  ??????????????????????????????????????????CCIR-B/P
  AL????????????CCIR-I/PAL?????????CCIR-M/PAL?
• CCIR-D??????8MHz,????6MHz,?????,??????6.5MHz?????6
  25?,??50Hz,??15.625KHz?

27
FDM?????? (6)

• PAL????????????,??NTSC????????????,???????????????
  ?,?????????,????????????NTSC??????????,???????????
  ????????????????????????????????,???????????????,?
  ????????????????????,?????????????????????

28
FDM?????? (7)
????????????

29
FDM?????? (8)
????????????

30
FDM?????? (9)
?????? ?????? VHF??I(??) 48.5-92MHz VHF??III(?
?) 167-223MHz UHF??IV(???)
470-566MHz UHF??V(???) 606-958MHz

31
FDM??????????

• ATT (USA)
• FDM???????
• ??(Group)
• 12 ????? (??4kHz) 48kHz
• ???60kHz?108kHz
• ??(Supergroup)
• 60???
• 420kHz?612 kHz?????5??????FDM
• ??(Mastergroup)
• 10???

32
Analog Hierarchy ??????????????
?? Group ?? Super group ?? Master group ?? Jumbo
group

33
Analog Hierarchy ??????????????
34
Analog Hierarchy ITU-T??????
(ITU-T??)

35
????????????????????,???????????
????????????????,??????????????
Analog Hierarchy ITU-T??????
36
8.2 ????
37
TDM ??????
38
??????

• TDM - Synchronous Time Division Multiplexing
• ?????????????????????
• ??????????????
• ??????????????????
• ??(Time slot)???????,?????
• ??????????
• ??,??????????????
• STDM Statistical Time Division Multiplexing
• ??????(??????)

39
??TDM
40
TDM??
41
TDM????
42
TDM?????
???????????
43
TDM ????

• ??????
• ??????????
• ????
• ????????????
• ??????????????,?????????
• ??????????
• ?????????
• ????
• ???????????????

44
TDM???????
45
??(Framing)

• ????SYNC???TDM???
• ????????
• ????????(Added digit framing)
• ??TDM?????????
• ????????? - control channel
• ??????????????
• ??, ??? 01010101??????????
• ???????????????????????

46
?????
47
???
48
????

• ?? ????????????
• ????????????
• ???????????????????
• ???? - Pulse Stuffing
• ????? (????????) ?????????
• ????????????????? ?????????
• ?????????????,???????

49
???????TDM
50
TDM??????????

• TDM?????
• USA/Canada/Japan ??????
• ITU-T??????????
• ??????DS-1??
• 24??????
• ???????8?????1????????,??????T1?
• ??2481193??

51
T-1?
52
?????? ????

• ??????????????? (PCM, ??8000???)
• ??? 80001931.544Mbps
• ?6???5??8???PCM??
• ?6??7??? PCM???1?????
• ??????????????????????????

53
?????? ??????

• ????????????
• 23 ?????
• ?????????7??????????
• ?????????????
• ?24???????
• ???????? 8000756kbps
• ?????
• ???????????,?????????????
• ?????????8000648kbps
• ???59.6kbps, 104.8kbps, 202.4kbps

54
?????? ????????
55
??T-1??
????(??)??????????T-1??,?DDN ?,???????????????????
????
DSU Data Service Unit ?????? CSU Channel
Service Unit ??????
56
?????????

• DS-1 ??????????????
• ??24???
• ?????
• ????????????????DS-1
• DS-2?4?DS-1,?????? 6.312Mbps
• 1.544Mbps46.176Mbps
• ????????????????

57
TDM?? ??????

• PCM24???????
• ?1.544Mbps??????(T1??) ?????
• ???????
• PCM30/32???????
• ?2.048Mbps??????(E1??) ?????
• ???????

58
PCM24???????T-1 ??
59
PCM30/32???????2.048Mbps????????
?????? - ???32?????,????8??,???256??
- ?????0?? - ?????16?? -
?????1????15????17????31??
?N?
?N1?
?N-1?
...
31
0
1
...
15
16
17
31
0
...
...
????
????
????
????
PCM?????8KHz,1???8???????????8Kbpsx864Kbps?????
? 64Kbpsx322.048Mbps?
1
2
3
4
5
6
7
8
60
TDM???????????????? DS Hierarchy
PCM24???????
?????
?????
?????
DS-0 64Kbps DS-1 24 DS-0 DS-1C 48
DS-0 DS-2 4 DS-1 96 DS-0 DS-3
7 DS-2 672 DS-0 DS-3C 14 DS-2 1344
DS-0 DS-4 6 DS-3 4032 DS-0 DS Digital
Signal service ??????, ??T??????(T1-T4)
61
?????????PDH (Plesiochronous Digital Hierarchy)

• PDH????????????
• ????????????

(????)
62
ISDN??????

• ISDN?????ISDN?????????
• ????
• ISDN??????(BRI Basic Rate Interface)
• ISDN?????(PRI Primary Rate Interface)

63
ISDN??????(1)

• ??????NTE?????????????
• ???????????
• ????????
• 1???, 0??????? 750mV /-10
• ???192kbps
• ???????64kbps?B?????16kbps?D??
• ??192kbps??????,??144kbps???
• ???????????

64
ISDN??????(2)

• B??????????
• ??
• PCM??
• ???????????64kbps????
• D?????????
• LAPD?
• ??48???
• ?250?s??

65
ISDN?????????
66
ISDN?????

• ???
• ?????PBX
• 1.544Mbps
• ????DS-1
• ?? T1??
• 23? B???1? D ??
• 2.048Mbps
• ??????
• 30? B ???1? D??
• ???????HDB3?AMI

67
ISDN????????
68
Sonet/SDH

• Synchronous Optical Network (ANSI)
• Synchronous Digital Hierarchy (ITU-T)
• ????
• ??????
• Synchronous Transport Signal level 1 (STS-1)?
  Optical Carrier level 1 (OC-1)
• 51.84Mbps
• ??DS-3????????? (DS1 DS1C DS2) ?? ITU-T ??(??
  2.048Mbps)
• ??STS-1 ?? STS-N??
• ITU-T ?????? 155.52Mbps (STM-1,???STS-3)

69
SONET STS??????
STS-3???SDH???????STM-1
70
Figure 20-16
??? STS-3????ATM
71
SDH/SONET???

• PDH ?????
• PDH????????????????????????????(??)
• PDH??????,T???J???E?????????
• ??????PDH???????????,??????,???????
• SDH????
• ?ITU-T?SONET??????SDH
• ???????????
• ???????????????

72
140Mbps?????2Mbps??????????
73
????????SDH (Synchronous Digital Hierarchy)

• SDH/SONET????????????(????)

74
SONET/SDH???
75
SONET STS-1???????
76
SONET??
77
Figure 20-3
SONET??
78
SONET????????
79
Figure 20-5
SONET??????
80
Figure 20-7
STS-1 ???
81
STS-1 ?????(Section Overhead)
82
Figure 20-9
STS-1 ??????(Line Overhead)
83
Figure 20-10
?????(Payload Pointers)
84
Figure 20-11
STS-1?????? (Path Overhead)
85
Figure 20-12
?????(Virtual Tributaries)
86
Figure 20-13
VT??
87
Figure 20-14
STS-n
88
SDH????

• ??????????????STM-N
• ????270 x N????9???
• ??????,????
• STM-1??
• 270?x9?x8??x8000?/s155.52Mbps
• STM-4 270x4x9x8x8000/s622.08Mbps
• STM-16270x16x9x8x8000/s2488.32Mbps
• STM-64270x64x9x8x8000/s9953.28Mbps
• ??SOH, Payload, POH, AU PTR

89
???????????????? SDH????
???4?, ?1??9xN? ???9xN
90
SDH?????

• ????(C)
• C-11 1.544Mbps(T1,J1), C-12 2.048Mbps(E1)
• C-2 6.312MbpS(T2,J2), C-4 139.264Mbps(E4)
• C-3 44.736Mbps(T3), 34.368Mbps(E3)
• ???(VC)????POH
• ????(TU)??????(TUG)
• ????(AU)??????(AUG)

91
SDH???????? SDH???????
92
??TDM

• ???TDM????????
• ??TDM????????
• ?????????????????
• ????????????????????

93
??TDM
94
????
a. ????????
95
????
b. ????????
96
????
c. ??????????
???????????
97
TDM?STDM???

• STDM????????TDM?????????
• STDM????????????????????
• ??????????????????,??????????????????
• ??STDM??????????????????????
• STDM????????????,????????????

98
??TDM ???
99
??

• ??????????????????
• ???????????
• ?????????????????
• ??????????? (? 8.6)
• ?????????,?????

100
STDM?????

• I ??????
• R ?????????, ??bps
• M ?????????, ??bps
• a ??????????????
• 0ltalt1
• KM/IR ????????????????, a ltKlt1
• ??
• ???????? M, ??K0.25, ????????????????????TDM?4?

aIRltMltIR
101
STDM???????

• ??????????????????Poisson (??)???????????,???????
  
• ??Table 8.7

l average arrival rate in bps, is that
total potential input (IR) times the
fraction of time a that each source is
transmitting Ts service time in seconds, is the
time is takes to transmit one bit r utilization
or fraction of total link capacity being used N
amount of buffer space being used in the
multiplexer Tr average delay encountered by an
input source
102
? 8.7 ????????????????????

• Parameters
• l mean number of arrivals per second
• Ts service time for each arrival
• r utilization fraction of time server is busy
• N mean number of items in system (waiting and
  being served)
• Tr residence time mean time an item spends
  in system (waiting and
• being served)
• s r standard deviation of Tr
• Formulas

103
????

• ?1
• ??M ?50 kbps? r0.5, ?????? l ? 25kbps
• ?2
• ???????? l?5000bps
• ?????? M?5000bps, ????r?100
• ?????? M?7000bps, ? r is 71

104
????? (1)

• ?????1000????????.
• ???????,??l?M??5000bps,?r 100 ? M7000bps,?r
  71
• ?8.16a?????????????????????
• ?8.16b???????????????????????
• ??????
• ???????, ???????????
• ??80 ?????????????
• ?????,???????????????
• ?????????????r, ?????M (?????????)

105
???????

• ?8.16

106
????? (2)

• ????????
• ??????, r???0.8 ??????N2.4.
• ??, ????????????,????????????

107
???????

• ?????????????
• ??8.17

108
????????

• ADSL - Asymmetrical Digital Subscriber Line
• ????????????
• ????
• ???????????????
• ?????????
• 1 MHz ??

109
(No Transcript)
110
?????????????????
111
ADSL??

• ???
• ?????????????
• ????
• ???25kHz????
• ??????(POTS - Plain old telephone service )
• ??????(echo cancellation)? FDM ??????????
• ????????FDM
• ?????????
• ????????????????
• ???????????
• ????5.5km

112
ADSL????
113
????

• DMT - Discrete Multitone
• ???????????
• ??????????
• ???4KHz???
• ????????????????????
• 256?4KHz?????? (QAM256)
• ???????60Kbps???
• ??????15.36Mbps
• ??????1.5Mbps?9Mbps

114
??DMT???ADSL
115
DMT???
116
???ADSL????
117
DSL Family Tree
xDSL
VDSL
ADSL
HDSL
SDSL IDSL
HDSL HDSL2
ADSL RADSL G. Lite
1Meg Modem CDSL
118
xDSL

• High data rate DSL (HDSL)
• Single line DSL (SDSL)
• Very high data rate DSL (VDSL)

119
(No Transcript)
120
Assignments

• Required Reading
• Stallings chapter 8
• Web sites on
• ADSL
• SONET
• Exercises
• 8.1, 8.8, 8.9, 8.12, 8.13, 8.15, 8.18 (essential)
• 8.3, 8.4, 8.10, 8.11, 8.14, 8.16, 8.17 (optional)

121
????HDSL
HDSL???????????,?????????????????????????,,???
????????,???????,?????????????????2.048Mbps???????
??????,?????35???
HDSL?????????????????????????2Mbps??,????????
????????????????????(Private Branch eXchange,
PBX)????ISDN????????????????????????????????
122
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123
1. 2B1Q??
??HDSL?????????,?2B1Q????,????????????????PCM??
???????(????????2bit??,??2B1Q???????50)???,??????
?????????,??????????????1/2
124
2.????
??????????????
125
??????????????????????????????????????????
HDSL?????????????????????,????????????????????
?????,?HDSL????????????
126
3.HDSL??????
HDSL??????????????????????????????????
???????????????,???ITU-T G.703????2.048Mbps,??
?HDB3?PCM???NRZ PCM???????
??????????????????
127
??????HDSL???????????HDSL??????????
?????,?HDSL????????????,?D/A??????????????????
?,?????????????A/D???,???????,??????????,?????????
HDSL???????????
128
??ADSL
HDSL??????2?????,??????????????????,???????,??
??????????,????????????(ADSL)???
ADSL???????????????????????????,????,??ADSL???
????????,??????(?????)??1.59Mbps???????,??????(
?????)???16640Kbps????????????????????????????,??
???????
ADSL??HDSL?????????????????????ADSL?????HDSL??
???,?????????????????????????????????
129
?????ADSL????????????????????,????????????????
??????
1?????
ADSL????????????????????????????,??????
130
??????(POTS)????????,????????????????ADSL?????
?ADSL???????????????????????
DSL??????????????,?????????????????????????(??
?????ATM??),?11-2 ????????????????,??????????2.048
Kbps?????
131
2.???????
(1)??????
132
ADSL ????????????????,
??ADSL??????????????????????
(2)??
????????????????????????,??????????????????
??????,?????????,??????????,?????????,????????ADSL
????????????????????
(3)????
????????????,????????????,????????????????
????????,???????????ADSL??????????????????????
(4)????
?????????????,ADSL?????Reed-Solomon?????
,?????
133
3.DMT????
ADSL??????????????,?????????3
???????(QAM),?????????(CAP)??????(DMT)???
??1963?,????????(MIT)??????????????????????
????,??????????????????????,??????????DMT?????????
???????
134
4.ADSL???
(1)????
ADSL??????,?????69???,??,0-67
???DMT??,????????,????????????????(68 250?s) /69?
135
(2)????????
?????????????????,??????????????????
?0 ?????????????????????CRC?

???????

• ?????????????1,?????????????????????
  13 ??eoc???

• ????????????????0, ????????????????7??
  ?????

• ??1?34?35?24????????????????????,????????
  ASX(X0,1,2,3)???????LSX(X0,1,2)???,AEX?LEX
  ?????ASX?LSX???????

????????????FEC????
136
(3)????????
?????,???????????????,????????1???????
??
5.ADSL??????
137
?????? (CDMACode Division Multiple Access)

• CDMA?????????????????????
• ????????,?????/?????
• CDMA???????????
• ?????????????,???????????????????????
• ??????,?????????(?????),?????????????????????????,
  ????????????
• ?????????????,????????/?????????????????????,?????
  ????????,CDMA??????????
• ?????CDMA????
• ???(PN)???????????

138
??????

• ???CDMA????????,?????????????????,????????????
• CDMA??????????,????,???????,??????????????
• PN???????????????

139
???????????????? ??????????