Notes “GSM Radio Network Overview”: During my study / preparation for ETCP Exam, these Notes were made on GSM Network !t wi"" #$er$iew %e"ow "earning o%&e'ti$es, and may it wi"" %e usefu" for those who are seeking fast high"ights on the GSM (adio Network node fun'tions ) features
Learning Objectives:
* Des'ri%e the (adio Network 'omponents, their fun'tions, features features and re+uired spe'i'ations - #ut"ine Eri'sson.s produ't portfo"io C#(E nodes, 0''ess network, and transport network 1'onne'ting them23 -* Exp"ain Core nodes. fun'tion in %rief -- Exp"ain that the 4SC 'ontro"s the radio resour'es for the (4S 5 Ca"" 6"ow 5 #ut"ine the main main working fun'tions fun'tions of a 4SC, 4SC, T(C T(C and (4S (4S 5 7ist the di8erent di8erent $ersions of (4S.s 1-999 1-999 Series2 -: #ut"ine Transmission 1M!N!;7ink2
1. Describe the Radio Network components, their functions, features and required specications
5 (adio (adio Network pro$ides pro$ides fu"" Dup"ex Dup"ex 1<7/D72 Transmission Transmission system, system, %y pro$iding pro$iding 6re+uen'y 6re+uen'y 4and on 0ir !nterfa'e 5 Eri'sson 6re+ 6re+ 4ands 4ands 1GSM=99, >99, >99, *>99, *=992 5 The 4ands are di$ided di$ided in e+ua" 4? 'arriers, 'arriers, ea'h one pro$ide > TS a$ai"a%"e a$ai"a%"e to ser$e > di8erent users 5 The
5 MSC ser$i'e ser$i'e area stored stored in 7( 5 P7MN Pu%"i' Pu%"i' 7and Mo%i"e Mo%i"e Network Ser$i'e Ser$i'e 0rea 0rea @ 'o$erage area for one one network operator
2. Outline Ericssons product portfolio ! "ORE nodes, #ccess network, and transport network $connectin% them&'.
5 GSM System 0r'hite'tur 0r'hite'ture e is di$ided di$ided horionta""y into into : "ayers 10pp"i'ation, 10pp"i'ation, 'ontro" 'ontro" and 'onne'ti$ity2 5 MSS is 'om%ination 'om%ination of - nodes nodes 1MSC;Ser$er ) M;MG?2 5 MSC;Ser$er 1Contro" 1Contro" 7ayer2/hand"e 7ayer2/hand"e the network network signa"ing and inte""igen'e inte""igen'e for setting up ) tearing down ) monitoring of CS 'a""s 5 M;MG? 1Conne'ti$ity 1Conne'ti$ity 7ayer2/hand"es 7ayer2/hand"es pro'essing pro'essing ) transport transport of the CS 'a"" 'a"" traF' ) inter 'onne'tion to externa" network su'h as PS ) P7MNs and internationa" Te"e'om Net 5 Conne'ti$ity 7ayer is %ased %ased on 1!P2 ) 0TM 10syn'hronous Transfer Mode Proto'o"2 Proto'o"2 5 Eri'sson.s produ't portfo"io is is di$ided into C#(E nodes, 0''ess network, network, and transport transport network 1'onne'ting them2
2.1 E(plain "ore nodes function in berife 5 Core Nodes Nodes MSC, M;MG?, M;MG?, GMSC, SGSN, SGSN, GGSN GGSN ) *+"(outs the 'a"" to Su% 4y o%taining routing info 6rom the 7( 4ased on in'oming info 6rom 7(, GMSC sent 'a"" set up re+uest to MSC ) +* is +* is responsi%"e to swit'h this 'a"" from PSTN/4SC to 4SC ) +"and"es 'ontro" "ayer fun'tions re"ated to 'ir'uit mode 'ommuni'ation ser$i'es within a "ayered ar'hite'ture en$ironment Mo%i"ity management and 'onne'tion management ser$i'es Transit swit'hing Getway Swit'hing/ Ser$i'e Swit'hing
Signa"ing transfer
) *N6orwards in'oming and outgoing !P pa'kets address to/from a mo%i"e station atta'hed to its 6orwards Ser$i'e area Pa'ket routing and transfer to/from SGSN ser$i'e 0rea Ciphering and 0uthenti'ation Session management/ mo%i"ity management 7ogi'a" 7ink management towards MS Conne'tion to 7(, MSC, 4SC, SMS;GMSC, GGSN #utput of 'harging Data ) **NPro$ide 'onne'ti$ity 'onne'ti$ity to !P ) Data Network and responsi%"e for reso"ution of !P address used %y MS.s own !P address (outer interfa'es towards externa" network 1!P Pa'ket2 GP(S session management ) 'ommuni'ation set up towards externa" network 0sso'iating the su%s'ri%er su%s'ri%er to the right SGSN of traF' #utput of 'harging 1GGSN 'o""e't 'harging info for ea'h MS ) /NR6"exi%"e 6"exi%" e a""o'ation of mo%i"e num%er 1MS!SDN2 Mo%i"e num%er porta%i"ity fun'tions 1to MS retain the MS!SDN when 'hanging the #perator2 ) 0RManage su%s'ri%ers pro"e, "o'ation and a'ti$ity 0uthenti'ation 0uthenti'ati on pro'ess 1for Su%s'ri%ers and the network2 Se'urity signa"ing and user data (oaming restri'tions Monitoring of 'a"" forwarding restri'tions
(emote 'ontro" e+uipment
) ONetwork operators monitors and 'ontro"s the network through #SS
2.2 E(plain that the " controls the radio resources for the R
5 0''ess Nodes 4SC, 4SC, T(C, T(C, (4S 14TS/Node42 14TS/Node42 ) Setting up, maintaining and terminating radio 'onne'tions toward the termina"s ) 3and"es radio interfa'e to the MS 1Contain radio e+uipment antenna A trans'ei$er A '"uster of autonomous T(Hs2 5 Software Software stored and and exe'uted exe'uted in the T(H is 'ontro""ed, 'ontro""ed, "oaded "oaded and upgraded %y 4SC ) "and"es radio re"ated fun'tionsConguration fun'tionsConguration of network and hand"ing the 'onne'tions to MSs in'"uding # 0dministration 0dministra tion of resour'es in 4SS Super$ision of 4TS Conne'tion hand"ing of MS 7o'ating and ando$er 0dministration of Paging Transmission network management #peration and Maintenan'e of 4SS Boi'e 'odding if T(C is in same node with 4SC
) 3R"Mu"tip"exers Mu"tip"ex ers network traF' 'hanne"s to mu"tip"e 4SSs onto #ne IJK%its/s PCM 'hanne" Pro$ide trans'oding trans'oding of spee'h ) rate adaption of the data
) End userTE Termina" E+uipment used for GP(S system to transmit ) re'ei$e end user Pa'ket Data GP(S pro$ides !P 'onne'ti$ity %tw the TE ) an !SP or 'orporate 70N, 7 0N, 'onne'ted to the GP(S system MT Mo%i"e Termina"'ommuni'ate with TE ) o$er the air with 4TS MT is used in 'on&un'tion with GP(S, shou"d %e e+uipped with S? for GP(S fun'tiona"ity MT esta%"ished "ink to an SGSN 5 TE AMT@MS
) + can operate on 4 di5erent modes * C"ass 0 mode of operation a""ows an MS to ha$e a CS 'onne'tion at same time PS - C"ass 4 mode a""ows MS to %e atta'hed to %oth CS ) PS %ut 'ant use %oth at same time : C"ass C mode a""ows an MS on"y to %e atta'hed to one ser$i'e at a time
5 Su% !dentity Modu"e 1S!M2 Contain info info a%out su%s'ri%er su%s'ri%er 5 The info in S!M 6ixed Data ,%efore it is so"ed ex 1!MS!, 0uth Key, Se'urity 0"gorithm2 Temporary Net Data ex 17o'ation area of the su%s'ri%er ) for%idden P7MNs2 Ser$i'e Data ex 1"anguage preferen'e ) ad$i'e of 'harge2
) "all /low..
6"all /low $" call from +7 or 83N& * MS ask for signa"ing 'hanne" 1to express its re+uest2 - 4SC manage the signa"ing 'hanne" : 4SC/T(C a""o'ate TS for signa"ing J MS sent the re+uest 1'a"" setup2 to MSC/B7( L MSC/B7( instru't 4SC/T(C to a""o'ate id"e 0ir interfa'e TS I The (4S ) MS are to"d to tune TC MSC/B7( forwards the 'a""ed party num%er , 4;num%er, to ex'ha ex'hange nge PSTN > The 'onne'tion is esta%"ished 1if 4;num%er answer2
68 "all 9ow Se$era" users share one traF' 'hanne" ) the user pays for the amount of transmission data * MS atta'h atta'hed ed to Net 6o 6orr using using GP(S GP(S ser$i' ser$i'e e -
5 During a mo%i"e mo%i"e PS originating originating 'a"" MS sent the D0T0 to 4SC , 4SC send to SGSN re+uest for registering, then through M;MG? SGSN 'onta't GGSN, then GGSN 'onta't the #ST O!n 'ase of MT 1Mo%i"e Terminating Ca""2, same pro'ess wi"" take p"a'e from #ST, there 'an %e more than one P7MNs 5 4SC Management Management ) Conguration Conguration of 'e""s 'e""s ) the radio radio network, it 'ontain CP 1Contro" 1Contro" the 0HE, its 'ontro"s ) 'ommuni'ate the app"i'ation ? through 1(Ps2, ETC 1Ex'hange Termina" Cir'uit, to 'onne't 4SC to 4TS ) MSC/B7(2, ETC 4oard pro$ide an E*/T* PCM interfa'e 66 "omponent of * GS 1Group Swit'h2 'onne't an in'oming 'hanne" with outgoing 'hanne", !t 'an swit'h IJk%ps on"y , "ower %it rate the Su%;rate Swit'h is used - T(C Spee'h 'oding ) rate adaption done here During the Ca"" 4SC instru't T(C to a""o'ate a T(0 de$i'e for the 'a"" T(C 'onrm the a""o'ation of T(0 , whi'h 4SC wi"" 'ontro" the ? where the fun'tion 1a""o'ating T(02 is imp"emented is 'a""ed T(04 1Trans'oder ) (ate 0daption 4oard2 6rom MSC 1!n'oming IJK%ps2 sent through GS to T(0 6our IJK%ps 'hanne"s are trans'oded to *IK%ps ) Mu"tip"exed onto IJK%ps 'hanne", and then sent out $ia GS to (4S on 0;%is 1PCM2 : T(0 Trans'odes spee'h at IJk%ps from MSC to *:K%ps ) send it to (4S, ena%"ing J 'ompresses 'hanne"s to %e mu"tip"exed onto IJk%ps 'hanne" 0dditiona" 'ontro" info :K%ps for 6( ) E6( in added to *: k%ps,then sent to (4S Max Data (ate at GSM per TS is =Ik%ps !n SCSD its higher sin'e MS used more TSs J DH< 1Dis'ontinues Transmission2, redu'e the interfa'e in the network ) sa$e %attery in the mo%i"e L T( 1Trans'ei$er and"er2, re+uired to 'ontro" (4S ) Trans'ei$ers and"ing the signa"ing 7ink 170PD2 %tw 4SC;4TS and"ing 7ogi'a" Channe" addressing addressing part of signa"ing to/from 4TS,MS Pro'ess Pro'es s measurement data from 4TS ) MSs I S(S1Su%rate Swit'h2 0""ow 'onne'tion of rate "ower than IJK%ps MSC1#ne "ink IJK%ps2GS1one IJk%ps2T(01one @JO*IK%ps2GSS(S @JO*IK%ps2GSS(S the data "ower than IJk%ps wi"" go to 4TS* ) - through GS ,S(S wi"" distri%ute them
PC< 1Pa'ket Contro"
OO4TS 'ontain 0ntenna System, (adio 6re+uen'y, Power 0mp"ier, ) Digita" Sugna"ing e+ 50"" these work on gi$en pair pair of fre+ one for Tx ) one for (x Signa"s
)R2::: replaceable units $R;s&, such as $D<;, d3R;, "D;, "<;,8;& 1. D<;- ser=es as central +ain "8; ;nit node. there is one DH< per (4S Pro$ides Pro$ide s (4S with an interfa'e to transport Net Through J 6ixed 6ixed E*/T* transport port and"e in'oming traF', 'ontro"s ) super$ises info ) send it to its destination within (4S Pro$ide fre+ referen'e signa"s ) timing signa"s for 'ir'uit within (4S Stores ) exe'ute (4S S? 1Stored on a remo$a%"e ash 'ard2 Contro"s the '"imate ) power system 2. d3R;- 2>3R< replaceable unit Transmits and re'ei$es one 'arrier Di8erent $ersions of dT(< a$ai"a%"e %ased on 16re+ 4and, ) Modu"ation Capa%i"ity2 6eatures a %ui"t;in hy%rid 'om%iner -Tx ) J(x 1-(x antenna termina"s are used for -;%ran'h di$ersityr di$ersityre'eption2 e'eption2 4. "D;- the "ombiner Distribution ;nit ena%"e 'onne'tion of - Tx Signa"s to - antennas Tx signa"s 'an %e - 'om%ined signa"s or un'om%ined pro$ide simu"taneous transmission ) re'eption on ea'h antenna 0mp"ies -(x signa"s from - antennas for further distri%ution in the Conguration Swit'h
?. 8;- 8ower uppl@ ;nit 0C ) DC Communi'ation with DH< and"es 0"arms 0d&usts $o"tage Pro$ides Pro$ide s power "imitations A. "<;- "onnection witch ;nit Cross 'onne'ts the CD< ) dT(< in the (x path 1makes it possi%"e to re'ongure re'ongure a 'a%inet with minimum of mo$ing or rep"a'ing of (H 'a%"es2 CH< is used in (4S-H9I on"y Mu"ti;4and Produ't Support %oth GMSK ) >;PSK #ne CH< 'an support up to : CD
R 2::: eriesO (4S-999series ha$e redu'ed the Net TraF' pro%"em to a "arge extend (4S-*9I 1outdoor2, (4S--9I 1intdoor2, (4S-:9>, and (4S-**I
6R2<:ASupport an a"most un"imited num%er of 'e""/site T(H 'onguration De'rease of tota" 'ost of ownership 1TC#2, Q(e"ia%i"ity, Simp"i'ity, ) Maintaina%i"ityR ?ide (ange of (4S 'ongurations ) exi%"e expansions on existing insta""ation Q'o$erage, 'apa'ity, )en$ironmenta" re+uirementsR
6R24:B $+icro>ase tation& : time 'apa'ity than (4S-:90$ai"a%"e for Jfre+ %and J 'arriers per 'a%inet, output power :Jd4m Q>99/=99R, ::,Ld4m Q*>99/*=99R support EDGE ) GP(S No 6ootprint
4oth !ndoor /#utdoor easy ) 6ast to insta"" Support 'apa'ity growth upto *-T(H Qthrough extension 'a%inetsR si"ent in operation from ;::C to AJLC
6R221A7211A igh 'apa'ity, high performan'e Qindoor/outdoorR Comp"ete indoor *-'arrier GSM site on 9,-Jm foot print, ) -J 'arrier (4S on 9,-Jm foot print !mpro$e Tx output power, fewer sites needed 1simp"ied to ro""out , ) redu'e 'ost of operations2
2.4 Outline 3ransmission $+CNC>ink& **BSS: transport network is TDM based; Transmission HUBs are applied to multiplex the traffic from seeral !BS sites on a transmission link towards BS"#T!"
*Transmission $%& 'M()( D+",- 'D++,- 'M()(./ink, *M()(./ink: suit cellular applications- because of it- flexibilit0- concernin1 capacit0- confi1urations- 2 space re%uired& 34roide medium capacit0. link for an0 network& 35ast deplo0ment in all pro6ect phases 3(t can be used an0where within within network&& where 7 to 78 9Mbps transmission lines are re%uired re%uired 3uickl0 mounted on existin1 buildin1 or structure 'as per re%uired,
*5amil0 )odes 'M()( /ink $- M()( /ink H"- M()( /ink T), *MINI Link E:
seeral terminals can be inte1rated into one common access module& 3Traffic routin1 2 reroutin1 within a network can be performed with minimum external cables& Diided into 9 3Traffic 'indoor 2 outdoor, 3(ndoor: ccess module is full0 independent of fre%uenc0 band 2 supplied diff ersions traffic capacitiesmodulation schemes- 2 s0stem confi1uration
3
*MINI-Link HC (Outdoor/Indoor Unit)
3Microwae for oice 2 data 3ualit0 2 Speed are ke0 characteristics 3(t proide Hi1h leel of redundanc0
*MINI Link TN (Network Element)
35rom H= installation point iew- there is '(ndoor and outdoor part, 3(ndoor part 'ccess Modulation Ma1a>ine 'MM,- ccess Termination Unit 'TU,, *)$ with MM contain 9 parts from functional 2 confi1uration point of iew 'this does not appl0 to )$ with TU,: 7& Basic )ode: Holds s0stem platform proidin1 traffic 2 s0stem control ex& Traffic routin1- multiplexin1 protectin1 mechanisms and mana1ement functions 2 the radio terminals 9& !adio Terminal: proide microwae Tx from 9x9 to ?9x9 Mbps operatin1 within @ to ?@AH> fre%& band&