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GSM Services
Service Category Service Comments
Teleservices Speech
SMS (Short Message
Full Rate 13Kbps
Point to Point Cell !roa"cast
!earer Services #synchronous $ata
Synchronous $ata
3%% & '%%bps
3%% & '%%bps
Supplementary Services Call For)ar"
Call !arring
Subscriber !usy* +ot Reachable
,nternational ,ncoming Calls
'%% M-./ 0p lin Fre2uency '%4'15 M-6/ $o)n lin Fre2uency '354'%
M-.
1%% M-./ 0p lin Fre2uency 171%4175 M-6/$o)n lin Fre2uency 1%541%
M-.
189 carriers/There are channels in each carrier/Channel
separation is 8%% K-./
Ciphering mo"i:ies the contents o: the eight interleave" blocs
through the use o: encryption techni2ues to the particular
mobilestation an" base transceiver station/
T)o types o: ciphering algorithms* calle" #3 an" #5* are use" in
GSM to prevent unauthori.e" net)or access an" privacy :orthe ra"io
transmission respectively/
#uthentication is the process o: uni2uely proving an i"entity to
a certain service* net)or or "evice an" the veri:ication o:
thegiven i"entity/The #uC is associate" )ith the -;R (-ome ;ocation
Register< in a GSM or 0MTS net)or/ ,t provi"esauthentication
parameters :or the authentication process such as authentication
triplets in GSM or authentication vectors )ithin0MTS
A3 - Authentication Algorithm#3 #uthentication algorithm use" in
con=unction )ith Ki the authentication ey an" R#+$ theran"om number
generate" in the #uC (#uthentication Centre< to pro"uce the
SR>S (Signe" Response< This variable is use"by the net)or to
authenticate a MS (Mobile Station< re2uesting net)or
resources/
>2uali.ation is the techni2ue use" to improve the re"ial lin
per:ormance/ That is to minimi.e instantaneous bit error rate
(,ntersymbol inter:erence
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Timing a"vance is a solution speci:ically "esigne" to counteract
the problem o: time alignment/ ,t )ors by instructing themisaligne"
MS to transmit its burst earlier or later than it normally )oul"/
,n GSM* the timing a"vance in:ormation relates to bit4times/ Thus*
an MS may be instructe" to "o its transmission by a certain number
o: bit4times earlier or later relate" to previousposition* to reach
its timeslot at the !TS in right time/ MaBimum 3 bit4times can be
use" in GSM systems/ This limits GSMnormal cell si.e to 35m
ra"ius/
# ;ocation #rea is a number o: cells ("e:ine" by the mobile
operator< throughout )hich a GSM 0MTSmobile )ill be page"/
;ocation in:ormation is maintaine" an" use" by the net)or to
locate the user :or call routing purposes/ The net)or registersthe
userDs location in a register calle" userDs -;R* )hich is
associate" )ith an MSC locate" in a P;M+ to )hich user
issubscribe"/ >ach !SS eeps broa"casting on perio"ic basis the
cell i"entities on Ebroa"cast control channelsD o: the cells
un"erits coverage/ The mobiles )ithin each cell eep monitoring this
in:ormation/
#s changes in location are "etecte" (:rom the last in:ormation
recor"e" by themBamples o: Multiple #ccess systems inclu"e T$M#
(Time $ivision Multiple #ccess< use" in GSM* C$M# (Co"e$ivision
Multiple #ccess< use" in 0MTS an" CSM#C$ (Carrier Sensing
Multiple #ccessCollis ion $etection< use" by >thernet/
Fre2uency $ivision Multiple #ccess is a techni2ue in )hich
multiple users o: a ra"io system are separate" in the
:re2uency"omain
http://bsscpopup%28%27../GSM/GSM.htm');http://bsscpopup%28%27../UMTS/UMTSSystem.htm');http://bsscpopup%28%27../UMTS/UMTSSystem.htm');http://bsscpopup%28%27../GSM/GSM.htm');http://bsscpopup%28%27../UMTS/UMTSSystem.htm');
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Co"e $ivision Multiple #ccess is a metho" :or "escribing
physical ra"io channels/ $ata inten"e" :or a speci:ic channel
ismo"ulate" )ith that channels co"e/ These are typically pseu"o
ran"om in nature* an" posses :avorable correlation propertiesto
ensure physical channels are not con:use" )ith one another/
S$CC- (Stan" #lone Control Channel< )hen not on a call
S#CC- (Slo) associate" control channel< Hhen )e are on a
call/
Ran"om #ccess Channel (R#C-
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