Tm hiu giao din A v cch khai bo trn BSC Huawei Ni dung ti: Phn 1: Tm hiu v Cng ty: (s cung cp cho em sau) Phn 2: Chuyn mn: A Tng quan h thng BSC6900

1. Gii thiu h thng BSC6900 Chc nng ca BSC trong mng GSM

Hnh 1.1: S m hnh mng GSMBTS: Base Trasceiver Station MSC: Mobile Switching Centre SGSN: Serving GPRS Support Node BSC: Base Station Controller HLR: Home Location Register GGSN: Gateway GPRS Support Node

BSC c nhim v qun l tt c ti nguyn v tuyn l :

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n nh, duy tr v gii phng knh v tuyn Qun l chuyn giao Qun l cc BTS X l tn hiu truyn v thch ng tc (khi TRAU c t trong BSC)

Mt pha BSC c ni vi BTS cn pha kia c ni vi MSC ca NSS. Giao din quy nh gia BSC v MSC l giao din A, cn giao din gia BSC v BTS l giao din Abis c im k thut ca BSC6900( 1MPS+ 2EPS):

Dung lng ln, kh nng tch hp cao: h tr 2560TRX ti FR v HR, lu lng ln nht l 16250 Erl, 4375 BHCA, 10240 PDCHs active(MSC_9) i vi mode BM/TC combined.

Cu hnh linh hot-

Nhiu mode vn hnh: vi h thng E1/T1 hoc STM1, BSC6900 v cc BTS c th s dng kiu star, chain v ring; vi h thng IP, BSC6900 h tr HDLC da trn Hub BTS

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Cu hnh phn cng linh hot: h thng c th cu hnh theo cc i hi khc nhau ca cc dch v ting ni v d liu trn min chuyn mch CS v PS

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Vc chn la ngun clock linh hot: c th thu t BITS (Building Integrated Timing Supply System) hoc trn giao din A

Cc thut ton qun l ti nguyn v tuyn linh hot: iu khin cng sut: thut ton ny lm gim cng sut pht ca BTS v MS trong khi vn gi c cht lng ng truyn cao hn mc ngng cho php. iu ny gip gim nhiu n cc knh khc v tit kim cng sut tiu tn ca MS. Chuyn giao: thut ton ny c th x l cc chuyn giao di bt k mi trng v tuyn no, gip ci thin QoS ca mng.

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Cp pht ti nguyn v tuyn: Da trn i hi v QoS v ti ca cell hin hnh. BSC6900 c th cp pht mt FR TCH hay mt HR TCH cho mt yu cu dch v. iu ny gip s dng hiu qu ti nguyn v tuyn v p ng cc yu cu thng tin.

Vic nng cp v m rng dung lng d dng. Vic bo qun v vn hnh tin li Nhiu tnh nng: h tr tuyn bo hiu 2M, vic ti u ng truyn Abis, Hub BTS qua HDLC, Gb qua IP. 2 Cu trc phn cng 2.1 Rack BSC 6900 c 3 kiu rack: - MPS ( Main processing subrack ) : rack x l chnh , cung cp giao din x l dch v , giao din OM v giao din Clock.

Hnh 2.1 MPS c cu hnh y mode BM/TC combined - EPS ( Extended processing subrack) : rack m rng, thc hin chc nng x l user plane v iu khin bo hiu.

Hnh 2.2 EPS c cu hnh y mode BM/TC combined - TCS ( Transcoder subrack ) : x l dch v CS v thc hin chc nng ca b iu chnh thoi v m ha thoi.

Hnh 2.3 TCS cu hnh full khi E1/T1 c dng giao din A

Hnh 2.4 TCS c cu hnh full khi STM-1 c dng giao din A 2.2 Subrack BSC6900 c 3 mode cu hnh subrack :

BM/TC separated BSC6900 c cu hnh vi MPS, EPS, and TCS (local or remote). c tnh : v tr ci t TCS l linh ng c th c ci t trong rack transcoder hoc b bn ngoi CN, v vy tit kim ti nguyn truyn i gia BSC6900 v CN . Nh , TCS c th c ci t trong cng cabinet nh l MPS hoc EPS.

BM/TC combined Board TCS c ci t trong MPS hoc EPS vi tn subrack khng thay i. c tnh: BSC6900 trong mode ny tch hp phn cng nhiu hn mode BM/TC sepatated. Khi m dung lng nh nhau, BSC6900 trong mode ny c mt vi cabinet v subracks.

A over IP Trong mode ny, lp 3 ca giao thc trn giao din A c tch hp trn giao din A l giao thc IP. Trong trng hp ny BSC6900 c cu hnh vi MPS v EPS nhng khng c TCS. Chc nng TC c thc thi MGW. c tnh : trong mode ny , BSC c thm vi cabinet v subrack, BSC6900 phi c cu hnh kt ni vi MGW.

Hin ti, Viettel ang s dng cu hnh mode BM/TC combined.V vy trong bo co ny ch tp trung phn tch BSC6900 hot ng mode combined.

Hnh 1.5 Cu hnh phn cng BSC6900 1.3 Ci t DIP switch cho subrack DIP switch c ci t trong subrack cu hnh s subrack.

DIP Switch c s dng kim tra c chn l, s 1 trong 8 bit phi l s l, phng thc ci t bit nh sau: 1. Set bit 1 to bit 5 nh yu cu. 2. Set bit 7 to ON.3. Kim tra s 1 trong 7 bit ca DIP Switch. Ch l set bit 8 gi nguyn

khng thay i..o o

Nu s 1 l chn th set bit 6 l OFF. Nu s 1 l l set bit 6 l ON.

Subrack c nh t 0 n 2 , v vy bt 8 c set l OFF.

Hnh 1.6 Cu hnh DIP Switch 2 Cu trc logic BSC6900 c chia lm 5 phn h :

Phn h chuyn mch ( Switching Subsystem ) Thc thi chuyn mch lu lng data, bo hiu v tn hiu OM . Phn h x l dch v (Service Processing Subsystem) Thc thi chc nng iu khin trong giao thc 3GPP v x l dch v ca BSC6900.

Phn h x l giao din (Interface Processing Subsystem) Cung cp port truyn tn hiu v ti nguyn, x l qu trnh truyn bn tin, v cho php tng tc d liu bn trong v bn BSC6900.

Phn h ng b clock (Clock Synchronization Subsystem) Cung cp tn hiu clock cho BSC6900 v cung cp tn hiu clock tham chiu cho trm c s .

Phn h OM (OM Subsystem) C th vn hnh v gim st trong trng hp : bo dng, bo tr khn cp v m rng dung lng .

Hnh 2.7 S cu trc logic ca h thng 2.1 Phn h chuyn mch ( Switching Subsystem ) - Cung cp chuyn mch MAC (Medium Access Control) bn trong subrack - Cung cp chuyn mch TDM (Time Division Multiplexing) bn trong subrack

- Cung cp chuyn mch TDM v chuyn mch MAC bn ngoi subrack - Phn phi tn hiu clock ti cc board x l dch v. Phn h chuyn mch gm cc board SCUa, TNUa, knh backplane tc cao trong mi subrack, cp cho gia SCUa v cp inter-TNUa. Kt ni inter - subrack Modul logic ca chuyn mch MAC chuyn mch lu lng d liu da trn IP, tn hiu OM, bo hiu . Chuyn mch c thc thi bi board SCUa v cp Ethernet gia cc board SCUa . Chc nng MPS nh l subrack chnh v ti a ba EPS c xem l subrack m rng. Kt ni hnh sao gia MPS v EPS c thit lp thng qua cp Ethernet gia nhng board SCU.

Hnh 2.1 Kt ni gia subrack thng qua cp cho gia board SCUa (MPS/EPS) Module logic chuyn mch TDM chuyn mch lu lng d liu da trn TDM c thc thi bi board TNU v cp inter-TNU. Kt ni hnh mesh gia MPS v EPS c thit lp thng qua cp inter-TNUa.

Hnh 2.3 Kt ni gia cc subrack thng qua cp inter-TNUa (MPS/EPS) 2.2 Phn h x l dch v (Service Processing Subsystem)

Chuyn tip d liu ngi dng iu khin qun l h thng Gii m v m ha knh v tuyn Bo v ton b d liu Qun l di ng iu khin v qun l ti nguyn v tuyn iu khin dch v qung b cell Trace bn tin ngi dng v thng tin h thng Qun l truy nhp v tuyn X l dch v CS X l dch v PS

Phn h ny bao gm board XPUa , board DPUc, v DPUd. Board XPUa x l bo hiu, board DPUc v DPUd x l dch v. 2.3 Phn h x l giao din (Interface Processing Subsystem)

Phn h x l giao din cung cp giao din IP v TDM.o

Port in E1/T1

o o o

Port quang STM-1 Port in FE/GE Port quang GE

X l bn tin trong mng chuyn mch.

Phn h ny bao gm cc board giao in Abis, A, Ater, Gb v Pb. ( board EIUa, OIUa, FG2a, PEUa) 2.4 Phn h ng b clock (Clock Synchronization Subsystem) Cung cp ti nguyn clock cho BSC6s900 v m bo tin cy ca tn hiu clock:

Tn hiu clock BITS (Building Integrated Timing Supply System) Tn hiu clock 8 kHz m rng Tn hiu clock LINE

BSC6900 cung cp tn hiu clock cho BTS trn giao din Abis . Ngun clock c ly t giao in A. Board s dng l GCUa. Clock external : c hai loi

Clock BITSo

Tn hiu clock BITS c ba loi : 2 MHz, 2 Mbit/s, v 1.5 Mbit/s. Tn hiu clock 2 MHz v 2 Mbit/s l tn hiu clock E1 v tn hiu 1.5 Mbit/s l tn hiu clock T1. Tn hiu clock BITS c hai loi mode: BITS0 v BITS1. BITS0 v BITS1 p ng ti port CLKIN0 v CLKIN1 trn board GCUa. BSC6900 c c tn thiu clock BITS thng qua port CLKIN0 hoc CLKIN1 trn board GCUa/GCGa .

o

Tn hiu clock 8 kHz external

Thng qua cng COM1 trn board GCUa board, BSC6900 c c tn hiu clock chun 8 kHz t thit b bn ngoi . Clock LINE Tn hiu clock LINE l tn hiu clock 8kHz c truyn t board giao din trong MPS ti board GCUa thng qua knh backplane. Tn hiu clock LINE c hai mode :LINE0 v LINE1.

Hnh 2.6 Cu trc logic ca phn h ng b clock 2.5 Phn h OM (OM Subsystem)

Qun l cu hnh d liu

Qun l bo mt Qun l thc thi Qun l cnh bo Qun l ti Qun l vic nng cp Qun k ti BTS Qun l nng cp BTS

Phn h OM bao gm board OMUa. 3 Cc loi Board mch 3.1 Board DPUc DPUc ( Data Processing Unit ), i vi MPS board DPUc c th ci t slots 8 n 11. i vi EPS, board DPUc c th c ci t trong slots 0 n 3, slots 8 n 13 v slots 14 n 27. i vi TCS, DPUc c th ci t trong slot t 0 n 3 v slot t 8 n 13 Board DPUc thc thi nhng chc nng sau :

Cung cp chc nng nh dng thoi v chuyn tip d liu . M ha v gii m dch v thoi Cung cp chc nng TFP (Provides the Tandem Free Operation) Khi MS calling v called dng cng chui m ha thoi, tn hiu thoi c m ha duy nht mt ln ti pha MS calling v gii m ti pha MS called. Vic ny trnh lp li m ha v gii m v ci thin cht lng dch v thoi.

Cung cp chc nng nng cao thoi T ng pht hin thoi hng

3.2 Board DPUd DPUd ( Data Processing Unit). Board DPUd c th ci t ti slot 8 n 13 trong MPS/EPS. Chc nng ca board DPUd:

X l dch v PS ng thi 1,024 knh active PDCHs (MSC-9) X l d liu gi T ng pht hin gi li

3.3 Board EIUa EIU(32-port E1/T1 circuit Interface Unit REV:a). Board EIUa c ci t trong MPS/EPS/TCS. i vi MPS ,board EIUa c th c ci t trong slot 14 v 19 v slots 24 n 27. i vi EPS hoc TCS, board EIUa c th c ci trong slots 14 n 27. Board EIUa cung cp ng truyn E1/T1 cho BSC6900. Board EIUa thc hin cc chc nng sau :

Cung cp 4 port in E1/T1 cho truyn dn TDM Truyn , nhn, m ha v gii m 32 E1s/T1s. Tc ng truyn E1 l 2.048 Mbit/s; tc ng truyn T1 l 1.544 Mbit/s. X l tn hiu da trn giao thc LAPD. X l tn hiu da trn giao thc SS7 MTP2. Cung cp chc nng TPS(Tributary Protect Switch) gia cc board EIUa active v standby. Cung cp kt ni OM khi TCS c cu hnh trn MSC H tr giao din A, Abis, Ater, v Pb

DIP Switches trn board EIUa

Board EIUa cung cp 5 DIP switches: S1, S3, S4, S5, v S6.

Hnh 2.7 Layout cu DIP switches trn board EIUa Khi dng cp xon 75-ohm, ng truyn tn hiu dng l mode khng cn xng E1. Trong trng hp u cui TX ni t , bt p ng trn DIP switch c xt u ON. Khi cp cp xon 120 ohm c dng, tn hiu dung mode cn bng E1, trong trng hp u cui TX ni t, bt p ng ca DIP switch c xt l OFF. Tt c cc DIP switches ca board EIUa board u mt phng trc ca subboard. 3.4 Board FG2a FG2a c 8-port FE hoc 2-port in GE interface. N c th ci t cng vi MPS hoc trong EPS. i vi MPS, board FG2 c th ci t trong slot 14 n 19 v slot 24 n 27. i vi EPS, board FG2 c th ci t trong slot 14 n 27. Nh cc board giao din khc, FG2 cung cp IP trn nn Ethernet. Chc nng ca board FG2a:

Cung cp 8 knh trn port FE hoc hai knh trn port GE Cung cp nh tuyn da trn backup v phn chia ti Cung cp chc nng tp hp kt ni ti lp MAC

H tr cc giao in A, Abis, v Gb

Ports trn board FG2a C 6 port 10M/100M Ethernet, 2 port 10M/100M/1000M Ethernet, v hai port u ra clock trn board FG2a. 3.5 Board GCUa Board GCUa cung cp tn hiu clock ng b cho h thng. Hai board GCUa c ci trn slots 12 v 13 trong MPS. Chc nng ca board GCUa :

Traces, pht, duy tr tn hiu clock ng b Board GCUa standby traces phase clock ca board GCUa active.

3.6 Board OIUa OIUa cung cp 1-port quang STM-1. Board OIUa c th ci t trong MPS/EPS/TCS. i vi MPS, board c th ci trong slot 14 n 19 v slot 24 n 27. i vi EPS/TCS board OIUa c th ci t trong slot 14 n 27. Board OIUa cung cp ng truyn STM-1 qua giao din A, Abis, Ater, v Pb. Chc nng ca board OIUa :

Cung cp 1 port STM-1 i vi ng truyn TDM Cung cp chc nng APS (Automatic Protection Switching) gia board OIU active v standby. Cung cp 1 knh STM-1 vi tc truyn 155.52 Mbit/s X l tn hiu da trn giao thc LAPD X l tn hiu da trn giao thc SS7 MTP2 Cung cp kt ni OM khi TCS c cu hnh trn MSC

H tr giao din A, Abis, Ater, v Pb

3.7 Board OMUa OMUa l board vn hnh v bo dng, board bt buc phi c. Mt n hai board OMUa phi c cu hnh trong BSC 6900. B rng ca board OMUa bng hai ln nhng board khc, v vy mt board OMU c ci t trong hai slot. Board OMU c th ci t trong slots 0 n 3, slots 20 n 23, hoc slots 24 n 27 trong MPS. Board OMU l module qun l BSC6900. N lm vic nh cu ni cho vic giao tip (LMT) v nhng board khc trong BSC6900. Chc nng ca board OMUa:

Thc hin chc nng qun l cu hnh, vn hnh, qun l li, bo dng, bo mt v qun l ti cho h thng. Cung cp LMT hoc user M2000 iu khin thng tin gia LMT hoc M2000 v board SCUa ca BSC6900

3.8 Board SCUa SCUa (c cp trong GE Switching network and Control Unit). Hai board SCUa phi c ci t trong slot 6 v 7 trong MPS/EPS/TCS. Chc nng ca board SCUa:

Cung cp chc nng qun l vn hnh Cung cp cu hnh v vn hnh ca mt subrack hoc ca ton b BSC6900 Gim st ngun, qut v mi trng ca cabinet. H tr chc nng port trunking H tr switchover active/standby C th kt ni inter-subrack Cung cp tng dung lng chuyn mch 60 Gbit/s Phn phi tn hiu clock v tn hiu RFN cho BSC6900

3.9 Board TNUa TNUa (TDM switching Network Unit ). Mt hoc hai board TNUa c th ci t trong slot 4 hoc 5 trong MPS/EPS/TCS. Board TNUa cung cp chuyn mch v phc v nh l mt trung tm chuyn mch cho dch v CS ca ton b h thng . Board TNUa thc hin chc nng :

Cung cp chuyn mch TDM 128 kbit/s x 128 kbit/s Cho php ti nguyn mng TDM

3.10 Board XPUa XPUa (eXtensible Processing Unit). Mt n hai board XPUa c th ci t trong MPS/EPS. i vi MPS , XPUs c th ci t trong slot 0 n 5, slot 8 n 11, slots 14 n 19, v slot 24 n 27. i vi EPS, c th ci t trong slot 0 n 5, slot 8 n 13 v slot 14 n 27. Chc nng ca board XPUa

Ty theo phn mm ci t, XPUa c phn thnh 2 loi: XPUa iu khin chnh v XPUa khng iu khin chnh. Board XPUa iu khin chnh c dung qun l ti nguyn mt phng ngi dng GSM, ti nguynmt phng iu khin, truyn ti nguyn trong h thng v x l dch v GSM trn mt phng iu khin . Board XPUa khng iu khin chnh c dng x l dch v trn mt phng iu khin . Board XPUa iu khin chnh Board XPUa iu khin chnh c bn phn h logic.

Phn h 0 ca board XPUa iu khin chnh l n v x l chnh MPU (Main Processing Unit). N c dng qun l ti nguyn mt phng ngi dng, ti nguyn mt phng iu khin, v truyn ti nguyn ca h thng. Cc chc nng c miu t nh sau:

Qun l ti nguyn mt phng ngi dng , qun l sharering ti ca ti nguyn mt phng ngi dng gia cc subrack Duy tr ti ca mt phng iu khin vi cc subrack, trao i thng tin ti trn mt phng iu khin gia cc subrack. Cung cp chc nng nh l chc nng iu khin logic chnh ca BSC6900 Chuyn tip bn tin yu cu kt ni RRC thc hin chia s ti nguyn mt phng ngi dng v mt phng iu khin trong BSC6900

Chc nng ca phn h 1 n 3 ca board XPUa x l chnh thuc CPUS (CPU for service) :

X l bo hiu lp trn qua giao din A, Um, Abis, and Ater X l bo hiu lp vn chuyn Cho php v qun l vic thay i ti nguyn cn thit cho vic thit lp dch v, thit lp bo hiu v kt ni dch v X l bo hiu RFN

Boar XPUa iu khin ph Board XPUa iu khin ph c 4 phn h logic. Bn phn h ca board iu khin ph ph thuc vo CPUS, x l dch v ca mt phng iu khin, c chc nng :

X l bo hiu lp di trn giao din lp A, Um, Abis, and Ater X l bo hiu lp vn chuyn

Cho php v qun l s thay i ti nguyn cn thit cho thit lp dch v, thit lp bo hiu v kt ni dch v. X l bo hiu RFN

4 Cc loi cp kt ni s dng trong BSC6900 Nhng loi cp kt ni trong BSC6900 .

Cp ngunCp ngun gm hai loi: cp ngun bn ngoi v cp ngun bn trong. Cp ngun c th l cp ngun -48V hoc cp ngun RTN. Cp ngun bn ngoi ly ngun t khung phn phi ngun (Power Distribution Frame) a n hp phn phi ngun (the power distribution box) ca BSC6900. Cp ngun bn trong ly ngun t hp phn phi ngun n cc module trong cabinet.

Cp ngun bn trong/bn ngoi

Cp ngun cho khi qut

Cp PGND Cp PGND bao gm cp PGND bn ngoi v cp PGND bn trong, cp PGND dng phn phi cho t ngun, subrack, subrack qut c lp v ca cabinet

Cp quang Cp quang c s dng kt ni board giao din quang ti ODF hoc cc NE khc. S lng cp quang c ci t da trn yu cu site.

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u ni cp quang c cc loi sau:

LC/PC-LC/PC: l loi cp quang single-mode hoc multi-mode, dng ni bo giao din quang vi NE khc hoc cc bo giao din quang khc. LC/PC-FC/PC: l loi cp quang single-mode hoc multi-mode LC/PC-SC/PC: l loi cp quang single-mode hoc multi-mode, dng kt ni bo giao din quang vi ODF.

Cp ng trc 75 ohm Cp ng trc 75 ohm l mt dng cp trung k, cp ny c ci t da trn yu cu site, cp ny kt ni board EIUa/ PEUa active / standby ti DDF hoc NE v truyn tn hiu lung E1.

Cp xon i 120 ohm Cp xon i 120 ohm l loi cp trung k, cp ny kt ni board EIUa/PEUa active/standby ti DDF hoc NE khc v truyn tn hiu E1.

Hnh : Cp xon i 120ohm active/standby

Cp inter- TNUa L loi c dng kt ni board TNUa cc v tr subrack khc nhau.

Pin14 A Pin1 A X2 X1

1

2

3 B X3 W2 W4 X4

Pin1 W1 W3

Pin14 B

Hnh : Cp TNU

Cp clock BITS y l cp truyn tn hiu clock ti board GCUa trong MPS. Tu theo tr khng ca cp tn hiu m cp tn hiu ng b BITS c phn thnh cp ng b ng trc 75 ohm hay cp chuyn i ng b 120-ohm

Cp clock hnh ch Y Cp ny dng truyn tn hiu clock 8kHz t board GCUa trong MPS n board SCUa EPS.

Hnh : Cp ng b hnh ch Y

Hnh : V tr lp t cp ng b hnh ch Y

Cp tn hiu clock Line Hai n bn cp tn hiu clock Line c dng truyn tn hiu clock Line nhn c t cc board giao din ca EPS n board GCUa. Mt u ca cp c ni n port 2M0 hoc 2M1 trn board giao din. Mt u khc c ni vo port CLKIN0 hoc CLKIN1 trn board GCUa.

Hnh : Cp tn hiu ng b

Cp thng C hai loi : cp thng c bc v cp thng khng c bo v, cp thng khng c bo v. Cp thng khng c bo v kt ni cc board SCUa trong subrack khc nhau, cp thng c bo v dng kt ni board FG2a/OMUa hoc cc thit b khc hoc board XPUa ti CBC.

Hnh : Cp thng c bo v

Hnh : Cp thng khng c bo v

Hnh : V tr lp t cp thng gia cc SCUa

Cp tn hiu gim st subrack Fan c lp Cp ny dng truyn tn hiu gim st ti subrack dch v. Thng thng, cpny s c ni t port MONITOR0 ca khi qut cho mi subrack (dng u connector DB15) n port Monitor ca subrack di cng (subrack 0) ca t BSC6900 (connector DB9).

Hnh : Cp tn hiu gim st khi qut

Cp tn hiu hp cnh bo L loi cp c s dng trong cc trng hp khc nhau, cp ny truyn tn hiu cnh bo ti hp cnh bo.

Cp tn hiu gim st cho b gim st ngun L loi cp dng truyn tn hiu gim st t b phn phi ngun n subrack thng qua subrack Fan c lp .

Cp giao tip EMU RS45 Dng truyn tn hiu gia BSC6900 v EMU .

5 Lu tn hiu 5.1 Flow tn hiu ca mt phng ngi dng 5.1.1 Flow tn hiu CS Sau khi mt cuc gi CS c thit lp trong mng GSM, MS v mng giao tip vi nhau thng qua flow tn hiu CS. Phng thc ca x l flow tn hiu CS thay i theo mode truyn trn giao din Abis v giao din A v mode cu hnh ca subrack BSC6900. Flow tn hiu CS trn Abis over TDM v A over TDM.

Hnh 3.3 Flow tn hiu CS trn ng uplink :1. Tn hiu CS ng ln gi t BTS ti board giao din Abis trong MPS/EPS. 2. Tn hiu CS c tch knh ti board giao din Abis. Mi tn hiu CS dng

mt TS 64kbit/s v c truyn ti board DPUc thng qua board TNUa.

3. Board DPUc thc hin m ha thoi v chuyn i tc trn tn hiu CS,

v chuyn thnh tn hiu PCM 64kbit/s. Tn hiu ny c truyn ti board giao din A thng qua board TNUa v sau n MSC qua giao din A. Flow ng xung th ngc li vi flow ng ln. 5.1.2 Flow tn hiu PS GSM Sau khi thit lp kt ni PS trn mng GSM, MS v mng giao tip vi nhau thng qua flow tn hiu PS. Flow tn hiu PS GSM thay i da vo mode truyn dn trn giao din Abis. Abis over TDM Ch :

Board trn giao din Abis c th l EIUa/OIUa/POUc,v board giao din Gb c th l board PEUa/FG2a/POUc/FG2c/GOUc. INT trong hnh l board giao din.

Hnh 3. Flow tn hiu PS trn ng uplink1. D liu gi c gi t BTS ti board giao din Abis trn MPS/EPS. D

liu dng mt n bn TS 16kbit/s trn giao din Abis, ph thuc iu ch v chui m ha , v d CS1-CS4 or MCS1-MCS9. 2. Board giao din Abis truyn d liu gi ti board TNUa, v truyn d liu ti board DPUd. 3. Board DPUd chuyn i dnh dng khung d liu v truyn d liu ti board giao din Gb thng qua board SCUa . 4. Board giao din Gb x l d liu gi d trn giao thc FR hoc IP v sau truyn n ti SGSN trn giao din Gb. Flow ng xung th ngc li vi flow ng ln. 5.1.3 OM Signal Flow

Flow tn hiu OM l bn tin truyn gia BSC6900 v LMT/M2000. LMT hoc M2000 vn hnh v gim st BSC6900 thng qua tn hiu OM. Flow tn hiu OM thay i da trn mode cu hnh ca subrack.

Hnh Flow tn hiu OM mode BM/TC combined Flow tn hiu OM trn BSC6900 nh sau: Flow tn hiu OM trn MPS1. Tn hiu OM c truyn t LMT hoc M2000 ti board OMUa

trong MPS. 2. Sau khi tn hiu OM c x l bi board OMUa, n truyn ti board SCUa trong MPS thng qua backplane ca MPS. 3. Board SCUa truyn tn hiu OM n board dch v vn hnh. Flow tn hiu OM trn EPS1. Tn hiu OM c truyn t LMT hoc M2000 ti board OMUa

trong MPS. 2. Sau khi tn hiu OM c x l bi board OMUa, n truyn ti board SCUa trn MPS thng qua backplane ca MPS. 3. Board SCUa trong MPS truyn tn hiu OM ti board SCUa trong EPS thng qua cp cho gia cc board SCUa. 4. Trn EPS, board SCUa truyn tn hiu OM ti board dch v vn hnh . 5.2Flow tn hiu mt phng iu khin . 5.2.1 Flow bo hiu trn giao din A Flow bo hiu trn giao din A cp n bn tin bo hiu c truyn gia BSC6900 v MGW/MSC.

A over TDM Trong mode A over TDM, Flow bo hiu trn giao din A thay i da trn mode cu hnh subrack 6900. Ch :

Board giao din A c th l board EIUa/OIUa/POUc, v board XPUa/XPUb x l bo hiu INT l board giao din.

Hnh 3. Flow bo hiu uplink trn giao din A mode BM/TC combined1. Trong MPS/EPS, board XPUa x l bo hiu da trn giao thc MTP3,

SCCP, v giao thc BSSAP. Sau tn hiu b truyn ti board giao din A thng qua board SCUa. 2. Board giao din A x l bo hiu da trn giao thc lp 2 MTP2, sau truyn bo hiu ti MSC qua giao din A. Flow ng ln th ngc li flow ng xung. Flow bo hiu trn giao din Abis Flow bo hiu trn giao din Abis cp ti nhng bn tin bo hiu c truyn i gia BSC6900 v BTS. Abis over TDM Ch :

Board giao din Abis c th l board EIUa/OIUa/POUc, v board XPUa thc thi x l bo hiu. . INT l board giao din.

Hnh 3. Flow bo hiu trn giao din Abis trong mode Abis over TDM1. Bo hiu t BTS c truyn n board giao din Abis trong MPS/EPS qua

giao din Abis v sau c truyn ti SCUa. 2. Board SCUa truyn bo hiu ti board x l bo hiu. Flow ng xung th ngc li vi flow ng ln.5.2.3 Flow bo hiu trn giao in Gb

Flow bo hiu trn giao din Gb l bn tin bo hiu truyn gia BSC6900 v SGSN. Ch :

Board giao din Gb c th l board PEUa/FG2a/POUc/FG2c,v board XPUa thc thi x l bo hiu . INT l board giao din.

Hnh Flow bo hiu trn giao din Gb Flow bo hiu uplink trn giao din Gb:1. Trong MPS/EPS, board x l bo hiu x l bo hiu da trn giao thc

NS v BSSGP, sau truyn tn hiu ti board giao din Gb thng qua board SCUa. 2. Board giao din Gb x l bo hiu da trn giao thc IP hoc FR v truyn tn hiu ti SGSN qua giao din Gb.

Flow tn hiu ng xung th ngc li vi flow tn hiu ng ln. Tm hiu giao thc BSSAP trn giao din A Giao din A c nh ngha l giao din truyn thng gia Network subsystem (NSS) v Base station subsystem (BSS) trong mng GSM.Trong h thng giao din A l giao din gia MSC (Mobile Service Swtching Center ) v BSC (Base Station Controller ).Thng tin qua giao din ny bao gm thng tin qun l trm gc ,qun l di ng,qun l kt ni . Cc giao thc bo hiu trn giao din A :

c trng bo hiu GSM trong giao din A c thc hin bi phn ng dng h thng trm c s Base Station Subsystem Application Path (BSSAP).

7 Gii thiu giao thc BSSAP ( Base Station System Application Part) BSSAP c s dng giao tip gia MSC v BSC. c chia lm 2 phn ng dng : - BSSMAP (Base Station System Management Application Part) y l giao thc c s dng truyn bn tin gia MSC v BSC nh paging, circuit management v handovers, reset. Hn na BSSMAP gm tt c cc bn tin qun l ti nguyn tn s RR gia MSC v BSC, nh cc bn tin tc v gia BSC v MSC. - DTAP (Direct Transfer Application Part). DTAP c dng qun l bn tin kt ni v qun l di ng ( CM & MM) gia MSC v MS truyn thng sut qua BSC. ngoi tr 3 bn tin ca MM: LOC_UPD_REQ, IMSI_DET_IND, v CM_SERV_REQ vn c BSC x l.

Hnh: Giao din A trn ngn xp giao thc OSI 7.1 Bn tin DTAP Bn tin DTAP c phn chia vo trong bn tin MM( Mobility management ) v bn tin iu khin cuc gi CC (Call Control). Bn tin DTAP khng c hiu bi giao thc BSSAP. Thay vo , bn tin DTAP c truyn i trong sut. - Bn tin MM bao gm i vi qu trnh nhn thc, yu cu CM service , thit lp li dch v, yu cu nhn bit, tch IMSI, cp nht v tr ( location update), trng thi MM, cp li TMSI,

- Bn tin CC bao gm mi lin quan ti cnh bo, th tc cuc gi, s kt ni , thit lp, iu chnh, gii phng, ngt, thng bo, query trng thi, bt u DTMF, v gi , phc hi nhng dch v b sung bao gm 7.2 Bn tin BSSMAP Bn tin BSSMAP c phn chia vo trong bn tin kt ni v hng v bn tin kt ni c hng. 7.2.1 Bn tin kt ni v hng Bn tin kt ni v hng bao gm blocking ( s ngn mch), unblocking, handover( chuyn vng) , ti nguyn, reset, paging,..-

bn tin block v unblock bao gm block v nhn bit block, bn tin unblock v nhn bit unblock. Nhm block v bn tin unblock bao gm nhm block, nhm nhn bit block, nhm unblock v nhm bn tin nhn bit unblock.

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Bn tin handover bao gm yu cu ng handover v bn tin p tr yu cu ng handover. Bn tin ti nguyn bao gm yu cu ti nguyn v bn in xc nhn ti nguyn Bn tin resetting bao gm reset v bn tin xc nhn reset ( ci t li)

7.2.2 Bn tin kt ni c hng Bn tin kt ni c hng bao gm i vi qu trnh assignment ( thit lp), chuyn vng ( handover), xa, nhn thc, mt m( ciper) Bn tin thit lp ( assignment) bao gm yu cu thit lp, thit lp hon ton v bn tin thit lp tht bi Bn tin handover bao gm yu cu nhn thc, p ng nhn thc v bn tin t chi nhn thc. Bn tin mt m bao gm lnh mode ciper v bn tin hon thnh lnh mode ciper. 7.3 Th tc BSSMAP Giao thc BSSMAP thc thi nhng chc nng sau y: 7.3.1 Qa trnh thit lp (Assignmet )

Mc ch ca th tc Assignment l m bo chc rng ti nguyn v tuyn dnh ring ng c th c cp hoc cp li cho mt MS theo yu cu ca n. Tuy nhin, truy cp ngu nhin ban u ca mt MS v thit lp ngu nhin ti mt knh DCCH c gn bi BSS v khng cn tham chiu ti MSC 7.3.2 Blocking v unblocking Th tc thit lp da trn MSC chn la ti nguyn v tuyn c dng. V vy MSC cn thng tin ca bt k circuit khng c dch v ti BSS. iu ny thc thi bng cch dng mt th tc simple blocking / unblocking. 7.3.3 Cp pht ti nguyn (Resource indication) Mc ch ca th tc cp pht ti nguyn l thng tin MSC nhng thng tin sau: S lng ti nguyn v tuyn dc phn chia ti BSS v sn sng cho lu lng mang thng tin. Ton b dung lng truy cp ti nguyn v tuyn iu ny khng th d dng ly c t lu lng m MSC ang mang. MSC c th chia nh thng tin vo trong ti khon phn chia handover external ( bn ngoi) 7.3.4 Reset Mc ch ca th tc reset l khi to BSS hoc MSC trong mt th tc b tht bi. V d, s tht bi ti BSS th kt qu l thng tin truyn i b mt, mt bn tin reset c gi ti MSC. y l bn tin c dng MSC gii phng mt cuc gi v xa tt c nhng tham chiu nh hng v t tt c cc circuit ti trng thi idle. Trong trng hp mt trng thi ti mt phn ca MSC hoc BSS, th tc xa c th dng xa phn nh hng. 7.3.5 Handover required Da trn nhng nguyn nhn sau , BSS s gi bn tin HANDOVER REQUIRED ti MSC thc thi handover cho mt MS vi ti nguyn dnh ring c thit lp: BSS xa mt bn tin m yu cu handover

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MSC khi to mt th tc yu cu lp lch handover v MS hin thi ang i chuyn vng. Thay i mt cell c yu cu ti mt cuc gi thit lp do nghn v d nh hng li

Bn tin Handover required truyn li vi mc u tin nh sau: bn tin handover command c nhn t MSC Bn tin Reset c nhn Tt c giao tip b mt vi MS, v bc chuyn b hy b Bc chuyn cui cng nh xa cuc gi

7.3.6 Cho php ti nguyn chuyn vng ( handover resource allocation) Th tc cho php ti nguyn chuyn vng c th MSC yu cu ti nguyn t mt BSS da trn yu cu chuyn vng. Mc dch BSS s d tr ti nguyn v i truy cp ca mt MS trn knh d tr . 7.3.7 Handover execution ( thc thi chuyn vng) Thc thi chuyn vng l x l ti MSC ch dn mt MS chnh ti mt ti nguyn v tuyn dnh ring trn mt cell khc. Nh thc thi chuyn vng, ti nguyn v tuyn s khng gii phng v ti nguyn mt t s khng nh du l idle cho n khi bn tin CLEAR COMMAND c nhn t MSC hoc khi to li xut hin 7.3.8 Gii phng ti nguyn v tuyn v ti nguyn mt t Sau khi thc hin xong, MSC gi mt CLEAR COMMAND ch ti BSS l gii phng ti nguyn v tuyn, bng vic nhn lnh, BSS khi to th tc xa trn giao din v tuyn, sau , BSS nh du bt k circuit mt t thit lp l idle v tr v bn tin clear complete n MSC. Trn vic nhn CLEAR COMPLETE , MSC gii phng bt k ti nguyn v tuyn c thit lp ti tng i ch. Nu mt ti nguyn gii phng c yu cu bi mt nguyn nhn t BSS, BSS s gi mt bn tin CLEAR REQUEST ti thng tin MSC khi to th tc gii phng, v vy gii phng ti nguyn v tuyn v mt t c thit lp vi MSC v BSS 7.3.9 Paging

Bn tin paging tt c MS gi thng qua BSSMAP l bn tin kt ni v hng. Khi BSS nhn mt bn tin paging resphone giao din v tuyn, mt s kt ni SCCP thit lp hng ti MSC. Bn tin PAGING RESPHONE c lm trong bn tin COMPLETE LAYER 3 ca BSSMAP v mang ti MSC thng qua kt ni bo hiu 7.3.10 iu khin lung Kim sot dng chy c thng qua ngn chn cc thc th xm nhp vo mng trong tnh trng qu ti. iu khin lung trn giao din A c thc thi bng cch iu khin lung u vo . 7.3.11 Nng cp Classmark Mc ch ca th tc nng cp classmark thng tin classmark nhn t MS . Trong iu kin bnh thng , BSS nhn thng tin classmark t MS v sau thng tin ti MSC. Trong trng hp khc, MSC gi ti thng tin classmard MS p ng ti BSS mi thng qua giao din A sau khi qu trnh chuyn giao hon thnh.-

Yu cu thng tin MM Reset SGSN Reset VLR Reset HLR Cu trc chung ca bn tin BSSAP

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8 Cu trc bn tin BSSAP

Hnh Mi quan h gia DTAP ng vi CC v MM, BSSMAP ng vi RR Ton b bn tin BSSAP b ng gi vo trong bn tin SCCP. Cu trc bn tin nh hnh di y:

8 hoc 16 bit u ca bn tin BSSAP c dng phn bit BSSMAP v DTAP.

Phn u ca DTAP c chiu di 2 byte (16bit) bao gm thng s phn bit bn tin ( 01 = DTAP) v nhn dng kt ni lin kt d liu (DLCI) . 3 bit u ca DLCI dng xc nh im truy cp dch v SAPI ( service access point identify) trong thng tin v tuyn 8. SAPI = 0 cho RR, MM v CC 9. SAPI = 3 cho SMS v SS Phn u ca BSSMAP c chiu di 1byte (8bit) , ch bao gm thng s phn bit ( 00 = BSSMAP ), trong BSSMAP khng c octet DLCI. Mt b ch th chiu di , ch th chiu di ca trng d liu theo sau header trong c hai trng hp BSSMAP v DTAP .

Hnh: nh dng ca bn tin BSSAP

Hnh : nh dng ca bn tin DTAP 10. Gii m bn tin BSSAP Phn tch bn tin CLR_CMD c dng h hexa v dng gii m. Mc ch y l nhn mnh cu trc bn tin BSSMAP , ni m mt thng s theo sau ch nh loi bn tin. Thng s y l trong trng hp CLR_CMD, c hai thng tin : thng tin header lp 3 v cause ( l do)

Hnh Phn tch bn tin CLR_CMD - Phn thng tin Header ca lp 3 bao gm phn bit giao thc PD v nhn dng s giao dch TI ,chng c ngha l s dng trn giao din Air. - Phn 2 Cause (l do ca bn tin) nhn bit l do ti sao ti nguyn v tuyn ring s c gii phng. Thng thng gi tr l 09 i din cho CC, ch ra rng CC yu cu gii phng kt ni khi cuc gi kt thc v 0B ch ra rng chuyn giao thnh cng. 1 BSSMAP BSSMAP dng cho c hai kt ni: kt ni c hng ( cho bn tin ko lin quan ti kt ni di ng nh paging ) v kt v hng ca SCCP (nh handover or circuit assignment) Bn tin DTAP lun lun gi mode kt ni c hng. Mt bn tin BSSMAP c bit l c s dng bi BSC thng tin cho MSC v s thit lp ca mt kt ni vi mt mobile khc. Bn tin c gi trong khung SCCP CR ( yu cu kt ni) ti mode kt ni c hng u , Thng tin ca bn tin

lp 3 cng s mang bn tin called initial MS, u tin lp 3 nhn c t MS ( v d l paging response, CM service request, or location updating request). Hnh di ch ra mt vi bn tin trao i gia hai tng i trong qu trnh location updating. Mt s bn tin BSSMAP v DTAP c minh ha. Bn tin Initial MS, trong trng hp ny l location updating request. SCCP mode kt ni c hng c th gii phng ti mt yu cu gii phng knh ( clear command v bn tin clear complete) hoc s dng mt cp khc ca RLSD v RLC

7 V d bo hiu BSSAP THIT LP KT NI RR : Thit lp kt ni v tuyn gia MS v mng nh hnh di y:

- MSC /VLR gi bn tin paging ti BSC kim tra vng nh v ni m thu bao ang ng, BSC gi mt lnh paging ti BTS trong vng nh v, yu cu paging c gi i trn cc knh paging ca mi cell. - Mobile yu cu cp mt knh dnh ring vi mt bn tin yu cu knh ngn bao gm mt yu cu ngu nhin v thit lp. BTS s gi yu cu vo trong bn tin yu cu mt knh. - BSC cho php mt knh dnh ring ( thng thng l SDCCH) v t BTS ti kch hot n Sau khi c xc nhn, lnh c thit lp ngay lp tc v gi n ti BTS v MS, gi mt knh chi tit ti MS. SERVICE REQUEST

MS bt u mode nhn thc trn lp LAPDm trn knh c gn. Khung c ti bao gm mt bn tin response paging. BTS nhn s thu nhn SABM v tr bn tin lp 3 t MS vo khung UA. MS so snh bn tin v gi ti bn va nhn l chc chn rng l ch mt ngi s dng ca mt knh cho php. Thit lp mt mode nhn thc LADm l ch ti BSC. Bn tin RR l piggybacked ti BSC. BSC bt u mt kt ni SCCP ti MSC v gi mt bn tin t MSC trong bn tin thng tin lp 3. CALL INITIATION

Mt bn tin set-up truyn t MSC ti MS. Tt c cn kt ni chi tit l bn gm trong bn tin. MS c th tha thun loi ca cuc gi trong bn tin confirmed call. Tt c bn tin CM u truyn thng qua BSS TRAFFIC CHANNEL ASSIGNMENT Khi MS v mng sn sng cho mt cuc gi. Knh SDCCH c thay th bi knh lu lng TCH.

Khi yu cu assignment c nhn t MSC, BSC cho php mt transcoder trong TRC v thc thi bo hiu ( bt u ca kt ni SCCP , bn tin BTAP) v cho php knh lu lng sn sng trong BTS. Khi TCH sn sng, lnh assign truyn trong sut gi t BSC ti MS, t MS chuyn ti mt channel mi. u tin, mode nhn thc LAPDm c thit lp trn knh FACCH, mt vi ti nguyn nh TCH, nhng dng bo hiu v n ch nh ti BSC. Cui cng , xc nhn t MS v BSC l gi ti MSC, v knh SDCCH c c gii phng bi BSC ( Bn tin RF channel release) CALL CONNECTION

Khi mt thu bao bt u rung chung, bn tin alerting gi thng sut ti MSC, MSC gi ISUP ACM ( Address complete ) hng ti GMSC v tng i trc. Khi thu bao tr li cuc gi, bn tin connect gi ti MSC. Bn tin MSC nhn ti MS v gi ISUP ANM hng ti GMSC v tng i trc. Cuc gi thit lp hon ton v kt ni thng sut.

3. Cu hnh BSC6900 trn giao din A: 3.1 3.2 BSC6900 GSM Product Documentation : Installation and Commissioning > BSC6900 GSM Initial Configuration Guide > Configuring the Global Information> Configuring the Basic Data BSC6900 GSM Product Documentation : Installation and Commissioning > BSC6900 GSM Initial Configuration Guide > Configuring the Global Information> Configuring the OPC and DPC BSC6900 GSM Product Documentation : Installation and Commissioning > BSC6900 GSM Initial Configuration Guide > Configuring the Interfaces> Configuring a Board

BSC6900 GSM Product Documentation : Installation and Commissioning > BSC6900 GSM Initial Configuration Guide > Configuring the Interfaces> Configuring the A Interface (over TDM) 3.3. Trace bn tin trn giao din A v phn tch: