Intro To Gsm Wh080917

Introduction to GSM system

Wade Hwang

Introduction to GSM systemIntroduction to GSM system


23/4/8Introduction to GSM system,

Wade Hwang2

Outline

Migration of GSM system

History of public wireless communication

History of GSM system

Working principle of GSM system

Concept of GSM system

Main components

Network structure

Important interfaces

Features of GSM system


CDMA

GSM

TDMA

PHS (IP-Based)

64 Kbps

GPRS

115 Kbps

CDMA 1xRTT

144 Kbps

EDGE

384 Kbps

cdma20001X-EV-DV

Over 2.4 Mbps

W-CDMA (UMTS)

Up to 2 Mbps

2G2.5G

2.75G 3G

1992 - 2000+2001+

2003+

1G

1984 - 1996+

2003 - 2004+

TACS

NMT

AMPS

GSM/GPRS

(Overlay) 115 Kbps

9.6 Kbps

9.6 Kbps

14.4 Kbps/ 64 Kbps

9.6 Kbps

PDC

Analog Voice

Digital Voice

Packet Data

IntermediateMultimedia

Multimedia

PHS

TD-SCDMA

2 Mbps?

9.6 Kbps

iDEN

(Overlay)

iDEN

Source: U.S. Bancorp Piper Jaffray


Wade Hwang3




Wade Hwang4

1997

500

1000

2000

1000

2003

1500

400

2005

2000

2500

2007

3000

Global mobile-phone subscribers hit 2B (Oct 05)

3000Subscribers

(Millions)

UMTS 100 Million




Wade Hwang5


1982 1984 1985 1986 1987 1988 1989 1991 1992 1993 1994 2000 2001 2002 2003 2004 2006 2007 2008

Group Special Mobile (GSM) is formed by the

Confederation of European Posts and Telecommunications

(CEPT) to design a pan-European

mobile technology.

Trials of different digital radio transmission

schemes and different speech codecs in

several countries, with comparative evaluation by CEPT GSM in Paris.

Basic parameters of

the GSM standard agreed in February.

TDMA, RPE—LTP, GMSK

Completion of first set of

detailed GSM specifications

for infrastructure

tendering purposes.

first GSM call made

by Radiolinja in Finland.

Group Special Mobile defines

the GSM standard as the internationally

accepted digital cellular

telephony standard.

92 First international

roaming agreement

signed between Telecom

Finland and Vodafone (UK). First SMS sent.

02 95% of nations

worldwide have GSM networks.

06 GSM SURPASSES

TWO BILLION

CUSTOMERS.

03 First EDGE

networks go live.

First commercial

GPRS services

launched.

GSM surpasses 3

Billion connections



Wade Hwang6

Outline






Main components

Network structure





Wade Hwang7


GSM operation section (worldwide)

PLMN operation section (one or more in a country)

MSC operation section (one district controlled by a MSC)

LAI (Locating & paging district)

Cell (a specific area covered by a BTS)



Wade Hwang8

LAI (Location Area Identity)

Each location area of a public land mobile network (PLMN) has its own unique identifier which is known as Location Area Identity (LAI).

PLMN (Public Land Mobile Network)

A public land mobile network (PLMN) is a network that is established and operated by an administration or by a recognized operating agency (ROA) for the specific purpose of providing land mobile telecommunications services to the public. For example, in china, MNC (Mobile Network Code) of China Mobile’s GSM network is ‘00’, while China Unicom’s is ‘01’.

GSM operation section

Worldwide wireless communication network.

MSC operation section

One district controlled by a MSC

CELL

A specific area covered by a BTS




Wade Hwang9

Main components

NSS (Network Switching Subsystem)

It carries out switching functions and manages the communications between mobile phones and the Public Switched Telephone Network.

BSS (Base Station Subsystem)

Responsible for handling traffic and signaling between a mobile phone and the network switching subsystem.

OMC (Operations and Maintenance Center)

The functional entity from which the network operator monitors and controls the system.

MS (Mobile Station)MS refers to the Mobile Phone. i.e. the handset held by the users in the mobile network.



Wade Hwang10

Network structure and main interfaces



Wade Hwang11


Um - The air interface between the MS (Mobile Station) and the BTS.

Call control, measurement reporting, Handover, Power control, Authentication, Authorization, Location Update and so on.

Abis - The interface between the BTS and BSC.

BTS supervision and telecom signaling, and carries synchronization from the BSC to the BTS and MS.

A - The interface between the BSC and Mobile Switching Center.

Carrying Traffic channels

Ater - The interface between the BSC and Transcoder.

Gb - Connects the BSS to the Serving GPRS Support Node (SGSN) in the GPRS Core Network.



Wade Hwang12

Outline






Main components

Network structure





Wade Hwang13


Spectrum efficiencyImproved spectrum efficiency due to new technologies utilized such as efficient modulator and demodulator, channel coding, Interleaving, equalization and Vocoder

System capacity3-5 times higher than TACS due to TDMA, half-speed Vocoder and other technologies adopted.

Voice qualitySame voice quality in the coverage where the signal strength is higher than threshold.

Open interfacesNot only open air interface but also open interfaces between system components, enables flexibility.

SecurityAuthentication, encryption and TMSI (temporary mobile subscriber identity).

RoamingSIM (subscriber identity module) and IMSI.



Wade Hwang14

Q&AThank you

Intro To Gsm Wh080917

Technology

Transcript of Intro To Gsm Wh080917