This document provides an overview of GSM fundamentals, including: - The basic components of a GSM network including the mobile station, base station subsystem, network switching subsystem, and operation and maintenance subsystem. - Identification numbers used in GSM including the mobile subscriber identification number, location area identification, cell global identification, and base station identification color code. - Interfaces and protocols used between GSM network entities, including the Um, Abis, and A interfaces.

1. OMA000001
GSM Fundamentals
ISSUE 3.3
Wireless Curriculum Development Section

2. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Contents
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
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3. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Objectives
On completion of this section
the student will be able to:
 Name the frequency spectrum
used in GSM
 Name the concept of frequency
reused.
 Name the two different cell types
and understand why and when
each would be used.
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4. The Frequency Spectrum
GSM 900
EGSM GSM EGSM GSM
880 890 915 925 935 960
MHz
Duplex Separation: 45MHz
Channel Bandwidth: 200KHz
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5. The Frequency Spectrum
DCS 1800
Base Station Receive Base Station Transmit
1710 1785 1805 1880MHz
Duplex Separation: 95MHz
Channel Bandwidth: 200KHz
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6. Frequency Re-Use
What is Frequency Re-Use?
Because frequency resource of mobile system is
very limited,
The different Subscribers must use the same
frequency in different place.
Of course, the quality of communication must be
ensured.
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7. Frequency Re-Use
How can we reuse frequency?
2
7(Site)X 1(Cell)
7 3
Re-use 2
1
6 4
5
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8. Frequency Re-Use
4(Site)X 3(Cell) 5
1
Re-use 7 9 6
3 2
5 11 8 10
1 4
9 6 12 7
2 3
10 5 11
1
9
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9. CELL
Omni
Omni-Directional Cells
1
120 Degree Sectors 1
120
degree 2
3
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10. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Contents
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
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11. Objectives
On completion of this section
you will be able to:
Draw the structure of GSM
Identify the functions of
each component
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12. GSM Network Components
NSS AUC
AUC
HLR
HLR
EIR
EIR
OSS OMC
OMC
MSC/VLR
MSC/VLR PSTN
SIM
SIM
ME
ME BTS
BTS BSC
BSC
MS BSS
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13. Mobile Station—MS
MS=ME+SIM
International Mobile Equipment
Identity (IMEI)
– Mobile Equipment
International Mobile Subscriber
Identity (IMSI)
– Subscriber Identity Module
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14. Subscriber Identity Module – SIM
 International Mobile Subscriber
Identity (IMSI)
 Temporary Mobile Subscriber
Identity (TMSI)
 Location Area Identity (LAI)
M G
 Subscriber Authentication Key
S
(Ki)
 Mobile Station International
Standard Data Network
(MSISDN),
it is optional.
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15. Base Station Subsystem – BSS
MSC
 The Base Station
Controller – BSC
 The Base Transceiver BSS TC/SM
Station – BTS TC/SM
 The Trans-coder – TC
and Sub multiplexer BSC
BSC
(SM)
BTS
BTS
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16. The Network Switching System
NSS AUC
AUC
HLR
HLR
OMC EIR
EIR
EC
EC PSTN
MSC/VLR
MSC/VLR
IWF
IWF
Mobile Switching Center – MSC
Home Location Register – HLR
Visitor Location Register – VLR
Equipment Identity Register – EIR
Authentication Center – AUC BSS
Inter-Working Function – IWF
Echo Cancellor – EC
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17. Mobile Service Switching Center – MSC
 Call Processing
 Operations and Maintenance
Support
 Inter-network & Inter-working
 Billing
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18. Home Location Register – HLR
 Subscriber ID (IMSI and MSISDN)
 Current subscriber VLR (current location)
 Supplementary service information
 Subscriber status (registered/deregistered)
 Authentication key and AuC functionality
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19. Visitor Location Register – VLR
 Mobile Status(IMSI detached/ attached)
 Location Area Identity(LAI)
 Temporary Mobile Subscriber Identity(TMSI)
 Mobile Station Roaming Number(MSRN)
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20. Equipment Identity Register – EIR
•White List
•Black List IMEI
Is Checked against White List
•Grey List
If NOT found,
checked against
Grey/Black List
If NOT found, checked IMEI
against White List Is Checked against Black/Grey List
indications
If found, returns a Black
or Grey List indicator
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21. Inter-Working Function – IWF
• Rate Conversion
• Protocol Adaptation
MSC
MSC
EC
EC IWF
PSTN
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22. Echo Canceller － EC
Echo takes place by GSM system delay caused by call processing,speech
encoding and decoding etc.
An Echo Canceller is used on the PSTN side of the MSC for all voice circuits
4-wire
2-wire 2- wire
Hybrid Hybrid
Generation of Echo at 2-wire to 4-wire Interface
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23. Operation and Maintenance Sub System
OSS(NMC)
OMC OMC
OMC
Region2 Region 3
Region 1
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24. Operation and Maintenance Center – OMC
OMC – R: OMC assigned specifically to
the Base Station Subsystem
OMC – S: OMC assigned specifically to
the Network Switching Subsystem
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25. OMC Functional Architecture
Event/Alarm Security
Management Management
MMI
OS DB
Fault Configuration
Management Management
Performance
Management
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26. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Contents
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
26
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27. Objectives
On completion of this section
you will be able to:
 Identify the protocols used
on the terrestrial interfaces
between the GSM system
entities
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28. GSM Interface
D
HLR
G H
VLR VLR C AUC
EIR
B F
MSC MSC
E
IWF EC EC IWF
A
TC
Um Abis
MS BTS BSC
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29. GSM Protocol
MS BTS BSC MSC
CM CM
MM MM
L3
BSSMAP
RR BSSMAP
RR
RR BTSM BTSM SCCP SCCP
L2 LAPDm LAPDm LAPD LAPD
MTP MTP
L1 SigL1 SigL1 SigL1 SigL1
Um½Ó¿Ú Abis½Ó¿Ú A½Ó¿Ú
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30. SigL1: 2MBps Trunks
HLR
OMC AUC
IWF EIR
MSC/VLR MSC/VLR
EC
EC
TC
BSC PSTN
BTS
BTS BTS
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31. 2MBps Trunks
Typical Configuration
TS 0 TS 1-15 TS16 TS 17-31
TS = Time slot
TS# Used for
0 Frame Alignment /Error Checking /Signaling
1-15 Traffic
16 CCS7 Signaling (Other TS may also the used)
17-31 Traffic
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32. Abis (LAPD) Interfaces
Frame check Information Address Flag
Flag Control
Sequence
last bit first bit
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33. ITU Signaling System CCS7
CCS7 Levels
OSI Layers MAP
7. Application BSSAP
TUP ISUP TCAP (DTAP+BSSMAP)
6. Presentation
5. Session SCCP
4. Transport
MTP Level 3
3. Network
2. Link MTP Level 2
1 Physical
MTP Level 1 2 Mb/s Trunk
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34. Abbreviation of CCS7
 MTP Message Transfer Part
 TCAP Transaction Capabilities Application
Part
 SCCP Signaling Connection Control Part
 TUP Telephone User Part
 ISUP ISDN User Part
 MAP Mobile Application Part
 BSSAP Base Station System Application Part
 BSSMAP BSS Management Application Part
 DTAP Direct Transfer Application Part
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35. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Contents
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
35
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36. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Objectives
On completion of this section
you will be able to:
Identify the system identification number
Identify the of mobile identification number
Identify the cell identification number
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37. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Service Area
System area
PLMN service area
PLMN service area PLMN service area
MSC service area... MSC service area...
Location area...
Base station area...
Location area...
......
Base station area...
Radio cell
Radio cell
...... ......
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38. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: MSC/VLR Number
CC NDC LSP
MSC/VLR number
The format is CC+NDC+LSP
CC ： Country Code.
For example: The CC of China is "86".
NDC ： National Destination Code.
For example: The NDC of China Mobile is
139 、 138 、 137 、 136 、 135.
LSP(locally significant part): is defined by Telecom operator.
For example: 86-139-00311
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39. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: HLR Number
The format is ： CC+NDC+H0 H1 H2 H3 0000.
CC ： Country Code.
For example: The CC of China is "86".
NDC ： National Destination Code.
For example: The NDC of China Mobile is 139 、
138 、 137 、 136 、 135.
H0H1H2H3 is defined by Telecom operator.
For example: 86-139-0666-0000.
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40. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: LAI
MCC MNC LAC
Location Area Identification
The LAI is the international code for a location area.
MCC ： Mobile Country Code ， It consists of 3 digits .
For example: The MCC of China is "460"
MNC ： Mobile Network Code ， It consists of 2 digits .
For example: The MNC of China Mobile is "00"
LAC ： Location Area Code ， It is a two bytes BCD
code(hex).
The value 0000 and FFFF is invalid.
For example: 460-00-0011 40
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41. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: CGI
CGI: Cell Global Identification
The CGI is a unique international identification for a
cell
The format is LAI+CI
LAI: Location Area Identification
CI ： Cell Identity. This code uses two bytes BCD
code(hex) to identify the radio cells within an LAI.
For example : 460-00-0011-0001
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42. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: BSIC
BSIC （ Base Station Identification Color Code)
NCC BCC
BSIC
NCC ： PLMN network color code. It comprises 3 bit. It
allows various neighboring PLMNs to be distinguished.
BCC ： BTS color code. It comprises 3 bit. It allows
distinction
between different radio frequency channels using the same
frequency in neighboring cells.
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43. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: MSISDN
CC NDC SN
National (significant)
Mobile number
Mobile station international
ISDN number
CC ： Country Code. For example: The CC of China is
"86".
NDC ： National Destination Code. For example: The NDC
of China Telecom is 139, 138, 137, 136, 135.
SN ： Subscriber Number. Format:H0 H1 H2 H3 ABCD
Example: 86-139-0666-1234
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44. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: IMSI
Not more than 15 digits
3 digits 2 digits
MCC MNC MSIN
NMSI
IMSI
MCC ： Mobile Country Code ， It consists of 3 digits .
For example: The MCC of China is "460" 。
MNC ： Mobile Network Code ， It consists of 2 digits .
For example: The MNC of China Telecom is "00" 。
MSIN ： Mobile Subscriber Identification Number. H1H2H3 S
ABCDEF
For example: 666-9777001
NMSI ： National Mobile Subscriber Identification ， MNC and MSIN
form it together.
For Example of IMSI : 460-00-666-9777001 44
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45. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: TMSI
TMSI: Temporary Mobile Subscriber Identification)
 The TMSI is assigned only after successful
subscriber authentication.
 The VLR controls the allocation of new TMSI
numbers and notifies them to the HLR.
 TMSI is used to ensure that the identity of the
mobile subscriber on the air interface is kept
secret.
 The TMSI consists of 4 bytes( 8 HEX numbers)
and determined by the telecom operator.
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46. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: IMEI
IMEI: International Mobile Station Equipment Identification
TAC FAC SNR SP
IMEI
TAC ： Type approval code. It is administered by the type
approval center.
FAC ： Final assembly code.It is administered by the
manufacturer.
SNR ： Serial number.It is issued by the manufacturer of the
MS.
SP ： Not used.
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47. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: MSRN/HON
MSRN: Mobile Subscriber Roaming Number
HON: Hand-over Number
 The MSRN is used to route the call to the MSC which MS
is currently located.
 The HON is used by the MSC-A to set up a connection to
the MSC-B during handover process
 Usually, MSRN and HON share the same numbering plan.
 The format is CC+NDC+individual number. CC and NDC
is the same as that of MSISDN. The individual number is
taken from a pool of numbers specially reserved for
MSRN.
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48. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: RSZI
RSZI (Regional Subscription Zone Identity)
RSZI
CC NDC ZC
Zone Code, Two octets
CC 、 NDC: same as that of MSISDN
ZC(Zone Code): is designed by telecom operator and
stored in the VLR.
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49. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Contents
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
49
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50. Objectives
On completion of this section
you will be able to:
Identify the types of physical channels
and logical channels
Name the 4 most commonly used channel
combinations
Understand the structure of multiframes
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51. Physical and Logical Channels
The physical channel is the medium over which
the information is carried
The logical channels consist of the information
carried over the physical channel
TDMA FRAME
0 1 2 3 4 5 6
0 7
Timeslot
The information carried in one time
The information carried in one time
slot is called a “burst”
slot is called a “burst”
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52. Traffic Channel
TCH
Traffic Channels
Normal Burst
Speech Data
TCH/FS TCH/HS
TCH/9.6 TCH/2.4
TCH Traffic Channel
TCH/FS Full rate Speech Channel
TCH/HS Half rate Speech Channel
TCH/9.6 Data Channel 9.6kb/s
TCH/4.8 Data Channel 4.8kb/s TCH/4.8
TCH/2.4 Data Channel 2.4Kb/s
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53. Control Channel
CCH Control Channels
DCCH BCCH
SDCCH ACCH
BCCH Synch. CH.
FACCH SACCH CCCH
SCH FCCH
Broadcast Control Channel – BCCH RACH
Common Control Channel – CCCH CBCH
Dedicated Control Channel – DCCH
Associated Control Channel – ACCH PCH/AGCH
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54. Broadcast Control Channel – BCCH
The information carried on the CCH
BCCH is monitored by the mobile
periodically when it is switched BCCH
on and not in a call downlink only
BCCH:Broadcast Control Channel
FCCH: Frequency Correction Synch.
Channel BCCH Channels
SCH: Synchronization Channel
SCH FCCH
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55. Common Control Channel – CCCH
CCH
The CCCH is responsible for
transferring control information
between all mobiles and the
BTS.
CCCH
RACH: Random Access Control
Channel
PCH: Paging Channel RACH CBCH
AGCH: Access Grant Control uplink downlink
Channel
CBCH:Cell Broadcast Channel
PCH/AGCH
downlink
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56. Dedicated Control Channel – DCCH
DCCH is assigned to a single
CCH
mobile connection for call setup
or for measurement and handover
purpose. DCCH
SDCCH: Standalone Dedicated
Control Channel
ACCH: Associated Control
Channel SDCCH ACCH
SACCH: Slow Associated Control
Channel
FACCH:Fast Associated Control
Channel
FACCH SACCH
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57. How to use these channel?
Power-off state
Search for frequency correction pulse FCCH
Search for synchronous pulse SCH
Unscramble system information
BCCH
Idle state
Snoop into paging message PCH
Send access pulse
RACH
Allocate signaling channel
Dedicated mode
AGCH
Set up the call SDCCH
Allocate voice channel
FACCH
Conversation
Release the call TCH
Idle state FACCH
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58. Call Setup Flow
MS BTS BSC MSC
Channel_req Channel_Required
Channel_Active
Channel_Active_Ack
IMMEDIATE ASSIGN COMMAND
First SABM Establish_IND(CM Service Req)
CR(Complete_L3_information)
CC
CM Service Accepted
Setup
Call Processing
Channel_Active Assignment_Req
Channel_Active_Ack
ASSIGNMENT COMMAND
SABM: Set asynchronous
balanced mode command-- First SABM Establish_IND
Initial access frame ASSIGNMENT CMP
Assignment_CMP
UA: Unnumbered Alerting
acknowledgement response
Connect
Connect Ack
Conversation
Disconnect
Release
Release Complete
Clear_CMD
Clear_CMP
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59. GSM Multiframe
TDMA Frames
0 1
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
0 1 2 3 4 21 22 23 24 25
26 – Frame Multiframes
TRAFFIC CHANNELS
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60. TCH Multiframe
Downlink Uplink
IDLE IDLE
 This is used to transmit a 25 25
Traffic Channel Combination
(TCH/ SACCH/FACCH). The
FACCH is not showed in the
diagram as it does not receive
its own time allocation. The
FACCH steals a time period 12 12
SACCH SACCH
from the TCH is required.
 The 13th frame is used by the
SACCH which carriers link
control information to and
from the mobile and BTS.
 The 26th frame is idle.
0 0
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61. GSM Multiframe
TDMA Frames
0 1
0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
0 1 2 3 4 46 47 48 49 50
51 – Frame Multiframes
CONTROL CHANNELS
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62. BCCH/CCCH Multiframe
Downlink
B B B B I
F S C C C C F S C C .. F S C C .. F S C C .. F S C C C C C C C C
0 10 20 30 40 50
F = FCCH (Frequency)
S = SCH (Sync.)
C = CCCH (Common)
I = Idle
R = RACH (Random)
Uplink
R R R R R R R R R R R R R R .. R R R ..R R R .. R R R R R R R R R R R
0 10 20 30 40 50
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63. SDCCH Multiframe
Downlink
D0 D1 D6 D7 A0 A3 I I I
D0 D1 D6 D7 A4 A7 I I I
0 7 24 32 44 50
D = SDCCH/8 (Dedicated)
A = SACCH/C8
(Associated) I = Idle
Uplink
A5 A6 A7 I I I D0 D7 A0
A1 A2 A3 I I I D0 D7 A4
0 7 12 15
6344 50
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64. Timeslots and TDMA Frames
Higher Capacity Cell
0 1 2 3 4 5 6
0 7
Broadcast Traffic
Dedicated
0 1 2 3 4 5 6
0 7
Traffic
Low Capacity Cell
0 1 2 3 4 5 6
0 7
Combined Traffic
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65. Combined Multiframe
Downlink
FS B C FS C C F S D0 D1 F S D2 D3 F S A0 A1 I
FS B C FS C C F S D0 D1 F S D2 D3 F S A2 A3 I
0 2 6 10 20 30 40 50
R = RACH (Random) B = BCCH (Broadcast)
F = FCCH (Frequency) S = SCH (Sync.)
C = CCCH (Common) D = SDCCH/4 (Dedicated)
A = SACCH/4 (Associated) I = Idle
Uplink
D3 R R A2 A3 R R R R D0 D1 R R D2
D3 R R A2 A3 R R R R D0 D1 R R D2
0 4 6 10 20 30 40 50
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66. Configuration Suggestion
Just one BCCH for one cell
FR: One SDCCH for two TRXs
HR: One SDCCH for one TRX
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67. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Contents
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
67
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68. Objectives
On completion of this section you
will be able to know about the
following radio technologies :
GMSK Modulation Techniques
Power Control
VAD, DTX, DRX
Diversity
Frequency Hopping
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69. Modulation Techniques
Amplitude Modulation (AM)
Frequency Modulation (FM)
Phase Modulation (PM)
– phase modulation can be implemented easily
for digital signals, this is the method which is
used for the GSM air interfaces. Phase
Modulation is known as Phase Shift Keying
when applied to digital signals
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70. Gaussian Minimum Shift Keying (GMSK)
Phase
1 0 0 1 1 Gaussian
Modulator
Digital Filter
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71. 8PSK – for EDGE
Modulating bits Symbol
EDGE: D3i, d3i+1, d3i+2 parameter l
Enhanced Data Rates For GSM Evolution)
(1,1,1) 0
(0,1,1) 1
(0,1,0) 2
(0,0,0) 3
(0,0,1) 4
(1,0,1) 5
(1,0,0) 6
(1,1,0) 7
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72. Power Control
Both Uplink and Downlink
power settings can be
8W
controlled independently
and individually.
0.8W
5W
Saves radio battery power
Reduces co-channel and
adjacent channel interference
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73. Battery Life
Power Control
Voice Activity Detection – VAD
Discontinuous Transmission – DTX
Discontinuous Reception – DRX
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74. VAD & DTX
Without DTX
Encoding the speech
silences at a rate of
500 bit/s rather
than the full
13Kb/s.
With DTX
If the mobile does
not transmit during
‘silence’ there is a
reduction in the
overall power
output requirement Comfort
Noise
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75. DRX
DRX allows the mobile station to effectively “switch off”
during times when reception is deemed unnecessary.
BCCH Multiframe P = Paging Channel
PPPPPP BCCH PP
MS Being MS in MS receive System MS in
paged listen mode listen mode
information 75
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76. Multipath Fading
• Diversity
• Frequency
Hopping
Time Dispersion
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77. Diversity
Approx. 10
wavelengths
When diversity is implemented
two antennas are situated at
the receiver. These antennas
are placed several
wavelengths apart to ensure
minimum correlation between
the two receive paths.
Compare or
The two signals are then add signals
combined, this ensures that a
low signal strength is less likely
to occur.
Resultant Signal
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78. Frequency Hopping
Each time the BTS or mobile transmits a burst, it
does so on a different RF carrier frequency.
Synthesizer Hopping:each frequency
timeslot on a given
transceiver can transmit
at a different frequency
Baseband Hopping: each
transceiver stays at the
same frequency and the
data is switched to the
appropriate transceiver.
time
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79. haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan:
haoxiuyan: Contents
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
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80. Objectives
On completion of this section
you will be able to:
State the future development
of digital cellular mobile
system
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81. GSM User World Wide
GSM will stay in the Lead, all professional Market
Forecasts say
300
250
200
150
100
50
0
1996 1997 1998 1999 2000 2001
GSM users world wide in millions
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82. Voice and Data Service
Service Data
amout
Voice
Today 2000 Time
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83. Mobile Communication and Internet
million
700
600
500
400
300
200
100
1995 1996 1997 1998 1999 2000 2001
Mobile Internet
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84. GSM Develop Path
3G
2Mbps
2.5G IMT-2000
384kbps
EDGE
2G 115 kbps
57.6 kbps GPRS
9.6 kbps HSCSD
GSM
1999 2000 2001
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85. Data rate of EDGE and GPRS
Kbps 59.2
60.0
54.4
50.0 GPRS 44.8
40.0
EGPRS
29.6
30.0
22.4
20.0
20.0 17.6
14.4 14.8
12.0 11.2
8.0 8.8
10.0
0.0
CS-1 CS-2 CS-3 CS-4 MCS-1 MCS-2 MCS-3 MCS-4 MCS-5 MCS-6 MCS-7 MCS-8 MCS-9
GMSK 8PSK
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86. Huawei EDGE Test Result
Downlink, 4 TS, MCS-9 ：
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87. Summary
Basic Concepts of Cellular Mobile System
GSM Network Components
Terrestrial Interface
Service Area and Number Planning
Channels on The Air Interface
Radio Technologies
The Future Development
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88. 88
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