GSM Fundamentals.ppt

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Wireless Curriculum Development SectionWireless Curriculum Development Section

ISSUEISSUE 3.23.2

GSM FundamentalsGSM Fundamentals



Security Level: InternalConfidential Information of Huawei.

No Spreading without Permission.

Contents

Basic Concepts of Cellular Moile S!stem

Service "rea and #umer $lannin%

GSM #et&or' Components

C(annels on )(e "ir Interface

*adio )ec(nolo%ies





Objectives

#ame t(e t&o different cell t!pes

and understand &(! and &(en

eac( &ould e used. Get t(e concept of fre+uenc!

reuse. #ame t(e fre+uenc! spectrum

used in GSM

,n completion of t(is section

!ou &ill e ale to-





CELL

Omni

1

120degree

23

,mni/Directional Cells

20 De%ree Sectors





Cell concept

HighwayHighway

TownTownSuburbSuburb

RuralRural

• Fle1ile net&or' plannin% ased on location natureFle1ile net&or' plannin% ased on location nature

• Smoot( andover no service de%radation &(ile suscrier moves4Smoot( andover no service de%radation &(ile suscrier moves4

• Fre+uenc! reuse same %roup of fre+uencies used in different cells4Fre+uenc! reuse same %roup of fre+uencies used in different cells4

SignalSignal

strengthstrength

distancedistance

• Cell - asic service area t(at can e efficientl! mana%ed ! t(e

net&or'

• ,ne ase station e+uipment to s&itc(5 transmit and receive calls4

per cell for comm. et&een MS and t(e net&or'

• Cell oundaries are defined ! BS si%nal stren%t(





26 M7

Uplin' MS to BS4

26 M7

Do&nlin' BS to MS4

f

200 87

96 M7:90 M7

;;

9<0 M7936 M7

=6 M7 duple1 spacin%

Frequency Spectrum GSM 9

;

;

For DCS:00- uplin' from >0 to >:6M75 do&nlin' is from :06 to

::0M7 >6M(7 eac( ? 3>= *F carriers . 96M7 duple1 spacin%.

t

f

200 87

;

;

200 87 1 26 @ 26 M7

) D M

" f r a

m e @ 0 . 6

> > m s 1

: ) S

;

;96

M7

:90 M7

!hysical channels


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Contents





*adio )ec(nolo%ies




Understand t(e structure of multiframes

On completion of this sectionyou will be able to:

Objectives

#ame t(e = most commonl! used c(annelcominations

Identif! t(e t!pes of p(!sical c(annels

and lo%ical c(annels




Logical channels

Logical ChannelsLogical Channels

CC"CC"#C"#C" $%#%$%#%S!EEC"S!EEC"

#C"&"' #C"&"'

()bps()bps

#C"&F' #C"&F'

*+)bps*+)bps ,-.&.-/)bps,-.&.-/)bps00F'1"'2F'1"'2 9-3)bps9-3)bps F' F'

Logical tra44ic channels

logical channels consist o4 the in4ormation carried over the physical channel-logical channels consist o4 the in4ormation carried over the physical channel-


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Logical control channels

CC"CC"

5C"5C"$C"$C" CCC"CCC"

SC"SC"

FCC"FCC"!C"!C" %GC"%GC" '%C"'%C"S$CC"S$CC"

5CC"5CC"

•$o&er Control indicator •cell ID 5 A"I 5 $AM# code•Aist of nei%(orin% cells

S%CC"S%CC"

Power & timing control RSSI & link quality

F%CC"F%CC"

Auth. and HO .

6 Frequency6correction channel7 used 4or MS 4requency correction-6 Frequency6correction channel7 used 4or MS 4requency correction-

6 Synchroni8ation channel7 used 4or MS 4rame synchroni8ation and 5S6 Synchroni8ation channel7 used 4or MS 4rame synchroni8ation and 5S

identi4ication-identi4ication-

5roadcast control channel7 used to send cell in4ormation-5roadcast control channel7 used to send cell in4ormation--'andom access channel7 4or dedicated channels assignment request'andom access channel7 4or dedicated channels assignment request

-%ccess grant channel7 used to assign dedicated control channels 4or the MS%ccess grant channel7 used to assign dedicated control channels 4or the MS

-!aging channel used to page 0alert2 MS!aging channel used to page 0alert2 MS-Standalone dedicated channel Supports the trans4er o4 data during connectionStandalone dedicated channel Supports the trans4er o4 data during connection

setupsetup

-Slo:&Fast associated control channels carrying in4ormation associated :ith theSlo:&Fast associated control channels carrying in4ormation associated :ith the

process being carried out on either the S$CC" or the #C"-process being carried out on either the S$CC" or the #C"-





#imeslots and #$M% Frames

Higher Capacity Cell / more than * 'F carriermore than * 'F carrier

Broadcast )rafficDedicated

)raffic00 1 2 3 ! " #

00 1 2 3 ! " #

$ow Capacity Cell / * 'F carrier* 'F carrier

Comined )raffic

0 1 2 3 ! " #





GSM Logical Channel

C(annel Comination

• Main BC comination BCC CCC

• DC comination SDCC: S"CC:• Comined C(annel Comination BCC CCC

SDCC= S"CC=

• )C comination )C:?F"CC S"CC





Structure o4 Logical Channel Combination

Frame6Main 5CC"

multi/frame 6)DM" Frames4 236.3:ms Do&nlin'

Group Group Group2

Group35=

same as

Group24

Grpup6

C(annel F S B= C= F S C= C= ;; F S C= C= I

Frame

#umer 0 2/6 </9 0 2/6 </9 20/39 =0 = =2/=6 =</=9 60

multi/frame 6)DM" Frames4 236.3:ms Uplin'

C(annel * * * * * * * * * * * * * *;;* * * * *

Frame

#umer 0 2 3 = 6 < > : 9 0 2 3/=< => =: =9 60

F-FCC S-SC B-BCC C-CCC I-IDAE *-*"C






Frame6Main S$CC"

multi/frame 6)DM" Frames4 236.3:ms Do&nlin'

C(annel D0= D= D2= D3= D== D6= D<= D>= "0= "= "2= "3= I I I

C(annel D0= D= D2= D3= D== D6= D<= D>= "== "6= "<= ">= I I I

Frame#umer

0/3 =/> :/ 2/6 </9 20/23 2=/2> 2:/3 32/36 3</39 =0/=3 ==/=> =: =9 60


C(annel"6

="<= ">= I I I D0=

D

=D2= D3= D== D6= D<= D>= "0=

C(annel"

="2= "3= I I I D0=

D

=D2= D3= D== D6= D<= D>= "==

Frame

#umer 0/3 =/> :/ 2 3 =

6/

:

9/

2223/2<

2>/

303/3= 36/3: 39/=2 =3/=< =>/60







Frame6Combined 5CC" multi/frame 6)DM" Frames4 236.3:ms Do&nlin'

Group Group Group2 Group3 Group= Grpup6

C(annel F SB

=

C

=F S

C

=

C

=F S

D0

=

D

=F S

D2

=

D3

=F S

"0

=

"

=I

C(annel F SB

=

C

=F S

C

=

C

=F S

D0

=

D

=F S

D2

=

D3

=F S

"2

=

"3

=I

Frame

#umer 0 2/6 </9 0

2/

6

</

920 2

22/

26

2</

2930 3

32/

36

3</

39=0 =

=2/

=6

=</

=960


C(annel D3= * * "2= "3= *;;* D0= D= * * D2=

C(annel D0= * * "0= "= *;;* D0= D= * * D2=

Frame

#umer 0/3 = 6 </9 0/3 =/3< 3>/=0 =/== =6 =< =>/60







Frame6#C"

)-)C I-IDAE "-S"CC

multi/frame 2<)DM" Frames4 20ms

C(annel ) ) ) ) ) ) ) ) ) ) ).";) ) ) ) ) I

Frame #umer 0 2 3 = 6 < > : 9 0/2－

202 22 23 2= 26

.)(e F"CC is not s(o&ed in t(e dia%ram as it does not receive its o&n

time allocation. )(e F"CC steals a time period from t(e )C &(en

re+uired.

.)(e 3t( frame is used ! t(e S"CC &(ic( carriers lin' control

information to and from t(e moile and B)S.





Frames hierarchy

#he hyper 4rame lasts 4or over + hours7 a4ter :hich ciphering and F" algorithms are restarted-#he hyper 4rame lasts 4or over + hours7 a4ter :hich ciphering and F" algorithms are restarted-







Service %rea

$AM# service area

......

S!stem area

$AM# service area

MSC service area...

Aocation area...

Base station area...

Radio cell

......

......

MSC service area...

Aocation area...

Base station area...

Radio cell

$AM# service area





L%;

Aocation "rea Identification

)(e A"I is t(e international code for a location area.

MCC： Moile Countr! Code， It consists of 3 di%its .

For e1ample- )(e MCC of C(ina is =<0

M#C： Moile #et&or' Code， It consists of 2 di%its . For e1ample- )(e M#C of C(ina Moile is 00

A"C ：

Aocation "rea Code ， It is a t&o !tes BCD

code(e14.

)(e value 0000 and FFFF is invalid.

For e1ample- =<0/00/00

MCC M#C A"C





CG;

)(e CGI is a uni+ue international identification for a cell

)(e format is A"ICI

A"I- Aocation "rea Identification

CI ： Cell Identit!. )(is code uses t&o !tes BCD

code(e14 to identif! t(e radio cells &it(in an A"I.

For e1ample - =<0/00/00/000

CGI- Cell Gloal Identification





CC ：

Countr! Code. For e1ample- )(e CC of C(ina is

:<.#DC： #ational Destination Code. For e1ample- )(e #DC of

C(ina )elecom is 395 3:5 3>5 3<5 36.

S#：

Suscrier #umer. Format-0 2 3 "BCD

E1ample- :</39/0<<</23=

MS;S$<

CC #DC S#

#ational si%nificant4

Moile numer

Moile station international

ISD# numer





MCC： Moile Countr! Code， It consists of 3 di%its . For e1ample- )(e MCC of C(ina is =<0。M#C： Moile #et&or' Code， It consists of 2 di%its . For e1ample- )(e M#C of C(ina )elecom is 00。MSI# ： Moile Suscrier Identification #umer. 23 S

"BCDEF For e1ample- <<</9>>>00#MSI： #ational Moile Suscrier Identification ， M#C and MSI#

form it to%et(er.

For E1ample of IMSI - =<0/00/<<</9>>>00

#ot more t(an 6 di%its

3 di%its 2 di%its

IMSI

MCC M#C MSI#

#MSI

;MS;





)(e )MSI is assi%ned onl! after successful

suscrier aut(entication. )MSI is used to ensure t(at t(e identit! of t(e

moile suscrier on t(e air interface is 'ept

secret. )(e )MSI consists of = !tes : E numers4

and determined ! t(e telecom operator.

#MS;

)MSI- )emporar! Moile Suscrier Identification4





;ME;

)"C F"C S#* S$

IMEI

)"C ： )!pe approval code. It is administered ! t(e t!pe

approval center.

F"C ： Final asseml! code.It is administered ! t(e

manufacturer.

S#* ： Serial numer.It is issued ! t(e manufacturer of t(e

MS.

S$： #ot used.

IMEI- International Moile Station E+uipment Identification





Contents





*adio )ec(nolo%ies





PSTNPSTN

OtherOther

GSMGSM

OMCOMC

GSM net:or) architecture

!ermanent data!ermanent data

-;MS;;MS;

-Suppl- service in4o -Suppl- service in4o -

-%uthentication )ey%uthentication )ey

-'oaming 1 billing in4o'oaming 1 billing in4o

#emporary data#emporary data

6MSC&=L' address6MSC&=L' address

#emporary data#emporary data

6copy o4 most o4 data 4or6copy o4 most o4 data 4or

active subscribers in =L'active subscribers in =L'

coveragecoverage

6Mobile status6Mobile status

6L%;6L%;

6#MS;6#MS;

Mobile Station 6 Mobile Equipment contains ;ME; 4or ME identi4icationMobile Station 6 Mobile Equipment contains ;ME; 4or ME identi4ication

6 Subscriber ;dentity module contains ;MS;7#MS;7L%;7%uth- )ey6 Subscriber ;dentity module contains ;MS;7#MS;7L%;7%uth- )ey

5ase #ransceiver Station the 4irst access point 4or mobile stations to access the5ase #ransceiver Station the 4irst access point 4or mobile stations to access the

net:or)- #he 5#S is a radio equipment 0transceivers 1 antennas2 needed to servenet:or)- #he 5#S is a radio equipment 0transceivers 1 antennas2 needed to serve

each cell in the net:or)-each cell in the net:or)-

5ase Station Controller controls one or more 5#Ss and inter4aces 5SS to <SS- ;t is a5ase Station Controller controls one or more 5#Ss and inter4aces 5SS to <SS- ;t is a

high capacity s:itch that provides handover7 cell con4iguration data-high capacity s:itch that provides handover7 cell con4iguration data-

Mobile S:itching Center controls one or more 5SCs and manages s:itchingMobile S:itching Center controls one or more 5SCs and manages s:itching

>hite list >hite list

=alid mobiles=alid mobiles

5lac) list 5lac) list

Stolen or 4orbiddenStolen or 4orbidden

Gray list Gray list

Faulty mobilesFaulty mobiles









Mobile to Landline call

MS BSS MSC HA* A* C"##EA *EUES) J*"CK

J"GCKDCC "SSIG#

JSDCCK

SIG#"AI#G AI#8

ES)"BAISED

*E. F,* SE*HICE C*CC

"U)E#)IC")I,#

SE) Cip(er M,DE

SE)/U$

JSDCCK

Call Info

EUI$. ID *E.

C,M$AE)E C"AA

C"AA $*,CEEDI#GJSDCCK

$S)#

SF,C

services "ut(.







Contents





*adio )ec(nolo%ies





,n completion of t(is section !ou&ill e ale to 'no& aout t(efollo&in% radio tec(nolo%ies -

H"D5 D)5 D*

Diversit!

Fre+uenc! oppin%

Objectives





5attery Li4e

$o&er Control

+oice %cti,ity -etection . +%-

-iscontinuous ransmission . -

-iscontinuous &eception . -&





=%$ 1 $#B

Encodin% t(e speec(

silences at a rate of

600 it?s rat(er

t(an t(e full

38?s.

If t(e moile does

not transmit durin%

Lsilence t(ere is areduction in t(e

overall po&er

output re+uirement

Wit(out D)

Wit( D)

Comfort

#oise





$'B

$C is structured so t(at MS 'no&s &(en it needs to c(ec' for a

pa%in% si%nal. In t(e time et&een pa%in% si%nals5 t(e moile

can %o into sleep mode5 &(en almost no po&er is used.

$ $ $ $ $ $ BCC $ $

BCC Multiframe $ @ $a%in% C(annel

MS Bein%pa%ed

MS inlisten mode

MS receive S!stem

information

MS inlisten mode





$iversity

W(en diversit! is implemented

t&o antennas are situated at

t(e receiver. )(ese antennas

are placed several

&avelen%t(s apart to ensure

minimum correlation et&een

t(e t&o receive pat(s.

)(e t&o si%nals are t(en

comined5 t(is ensures t(at a

lo& si%nal stren%t( is less li'el!

to occur.

Compare or

add si%nals

*esultant Si%nal

"ppro1. 0

&avelen%t(s





Frequency "opping

S!nt(esi7er oppin%-eac(

timeslot on a %iven

transceiver can transmit

at a different fre+uenc!

Baseand oppin%- eac(

transceiver sta!s at t(esame fre+uenc! and t(e

data is s&itc(ed to t(e

appropriate transceiver.

Eac( time t(e B)S or moile transmits a urst5 it

does so on a different *F carrier fre+uenc!.

time

fre+uenc!







f f f

Subscriber ;dentity Module ? S;M

Documents

GSM Fundamentals.ppt