n tt nghip

H thng tng i NEAXLI NI U

61ES pht trin ca h tng v c s thng tin l yu t quan trng thc y nn kinh t pht trin v gp phn nng cao i sng x hi ca con ngi. Tha k nhng thnh tu ca ngnh cng nghip in t, bn dn, quang hc, tin hc, cng ngh thng tin,nn cng nghip vin thng trn th gii c nhng bc tin nhy vt k diu a x hi loi ngi bc sang mt k nguyn vn minh mi: K nguyn thng tin. Pht trin v hin i ho thng tin ang l nhu cu bc xc ca nc ta. tin ti pht trin thng tin a dng, phong ph, ni bt l mng s a dch v DN (Intergrated Service Digital Netword). Thng tin s ng vai tr quan trng trong mng vin thng hin nay. Trong nhng nm gn y, cng vi s pht trin ca ngnh vin thng trn th gii, ngnh bu chnh vin thng Vit Nam cng t c nhiu thnh qu ln trong cng cuc hin i ho mng vin thng Vit Nam. Ho chung vi nhp iu pht trin ca th gii, cng bc trn xa l thng tin, Vit nam a c mt x dng in thoi c nh ln trn 9 my/100 dn. Trong h thng chuyn mch s ng vai tr quan trng trong mng vin thng. Trn c s , n tt nghip ca ti xin c cp n nhng ni dung nh sau: - Tng quan v tng i NEAX 61E - Cu trc phn cng v phn mm ca tng i NEAX 61E - Phn tch phn h chuyn mch ca tng i NEAX 61E c s hng dn tn tnh ca thy Nguyn Quc Trung v cc thy, c gio trong b mn, cng vi s n lc ca bn thn, em hon thnh n tt nghip ng thi hn. Nhng do iu kin thu thp ti liu v qu thi gian c hn, n ca em khng trnh khi nhng thiu st. Rt mong c s ch bo, ng gp kin ca cc thy c v cc bn. Em xin by t lng bit n i vi thy Nguyn Quc Trung cng cc thy c trong khoa in T Vin Thng gip v to iu kin thun li cho em hon thnh n tt nghip. H ni, ngy 12 thng 5 nm 2004

Sinh vin Trn Quang cTrn Quang c - Lp T2 - K46 Trang 1

n tt nghip

H thng tng i NEAX

61EPHN I GII THIU TNG QUAN V TNG I NEAX - 61EI. GII THIU CHUNG. Vi s pht trin ca ngnh Vin thng trong nhng phn t cu thnh mng th tng i ng vai tr ht sc quan trng. Hin nay trn mng li Vin thng Vit Nam c nhiu loi tng i, trong h thng tng i NEAX 61E gp phn khng nh trong cu hnh mng. H thng chuyn mch NEAX 61E(NEAX 61E Digital Switching System) l mt h cc tng i c mng chuyn mch theo nguyn tc phn chia theo thi gian (Time Divison) v c iu khin bng chng trnh ci t sn (Stored Program Controlled). H thng p ng c mt phm vi rng ln cc ng dng v to ra cc gii php v mng ph hp vi cc nhu cu thng tin a dch v. S linh hot cho php s la chn ti u v thit b, p ng c c mt kinh t v k thut. NEAX 61E l h thng chuyn mch c dung lng ln v tnh linh hot cao nh vic s dng my tnh v cng ngh in t vin thng mi nht. Nh vo vic s dng cng ngh bn dn mi nht, bao gm cc thit b c ch to t cc linh kin bn dn LSI (Large Scale integration), cng vi cu trc khi chc nng, h thng NEAX - 61 c cu trc v mt vt l nh hn v c hi qu kinh t hn cc h thng trc y. Nhng c im nh iu khi a x l cc mng gn nh khng tc nghn (Non Blocking) to nn tnh tuyt vi khi la chn h thng mi v m rng h thng. Tng i c p dng trong phm v rng, cung cp gi php tng th, nhiu dch v. H thng chuyn mch ny c tnh linh hot cao, n co th c ng dng nhng ni i hi dung lng cao, n c th c ng dng thnh ph, vng ng dn c hoc ng dng cho nhng ni dung lng thp nh phn mm linh hot, v medule ha phn cng. Ngoi ra tng i NEAX 61E cn c th c ng dng lm tng i quc t, toll... c thit k p ng cc yu cu a dng trong mng. II. TNG QUAN V H THNG. Kiu cu trc ca h thng chuyn mch chia thnh nhng lp c bn (thnh cc khi lp). c tnh chung ca h thng chuyn mch chia thnh nhng lp c Trn Quang c - Lp T2 - K46 Trang 2

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H thng tng i NEAX

61Ebn (thnh cc khi lp). c tnh chung ca h thng l c cu trc phn mm v phn cng theo kiu module c lp, bao gm cc module thit b hng dch v c iu khin tch bit, cng nh cc giao din chun v pha h thng chuyn mch v h thng x l. H thng c cu trc khi nh vy to ra nhiu kh nng ng dng v kh nng to dung lng ln bng cch cng thm cc module m khng cn thay i cu hnh c bn ca h thng. Trong cung mt h thng c trang b sn cc b x l a nng, vi x l chuyn nng, v cu hnh v tinh, nh vy cu hnh ny to ra kh nng hot ng mm do ti a cho tng i, c th ng dng lm tng i Local, Toll ... hoc nhu cu c bit nh in thoi di ng, h thng tr gip truyn thng. Kh nng ng dng ca h thng c a ra nh bng sau:NG DNG NG DY (MAX) LU LNG (MAX ) KH NNG X L (MAX)

Chuyn mch khu vc Tng i v tinh B tp trung thu bao Tng i qu giang Tng i quc t

100.000 line 10.000 line 4.000 line 60.000 circuit 60.000 circuit

27.000 erlange 1.000 erlange 336 erlange 27.000 erlange 27.000 erlange

1.000.000 BHCA 35.000 BHCA -----------------1.000.000 BHCA 700.000 BHCA

H thng tr gip 512 bn PO truyn thng TASS Ngoi ra h thng cn c kh nng kt hp vi nhiu h thng c bit khc nh h thng v tinh mt t, h thng v tinh Hng Hi quc t, tng i quc t ... nh m hnh sau:RLU IN MASAT DOMASAT LS TLS TASS RSU PAGING MTS MS TS INTS

NEAX 6E

Hnh 1: M hnh kt ni cc h thng ca tng i NEAX 61E Trn Quang c - Lp T2 - K46 Trang

3

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H thng tng i NEAX: n v chuyn mch xa. : H thng nhn tin. : Chuyn mch in thoi di ng. : Chuyn mch quc t. : Chuyn mch qu giang. : CM ng di (lin tnh). : Chuyn mch ni ht. : CM dnh cho ni ht v lin tnh.

61ETASS(Traffic Assistance Service Sytem): H thng phc v tr gip lu lng. RSU ( Remote Switch Unit ) PAGING MTS (Mobil Telephone Switch) INTS (Internationnal Switch) MS (Tandem Switch) TS (Toll Switch) LS (Local Switch) TLS (Toll Local Switch )

DOMSAT (Domactic Satelite System) : H thng v tinh mt t. INMARSAT RLU (Remote line Unit) Cc c trng c bn ca h thng: H thng vn hnh nh hai ngun cung cp l: Ngun mt chiu 48V DC (Direct Current). (Ngun ng dy). Ngun xoay chiu 3 pha 220V (hoc 115V) AC (Alternaling Current), tn s 50Hz (hoc 60Hz). Khi chuyn i DC/DC to ra cc in p 5V DC(ngun ligic) v 12V DC (truyn dn) cho tng khung thit b chuyn mch. Tt c cc thit b i hi dong mt chiu vi p ng danh nh 48V DC, cho php ngun mt chiu bin thin t 44V n - 58V ti u vo. c quy c th cung cp 3 gi lin tc khi mt in li. Bnh thng rng i c cp in t mng xoay chiu (ch np m), Khi mt in th t ng chuyn sang trang thai dung c quy hoc my pht in. vn hnh tp trung v thun tin cho vic bo dng, NEC s dng trung tm tnh ton iu hnh v bo dng (NCOM Nec Computerized Operation and Maintenance). : H thng v tinh Hng hi Quc t. : n v ng dy thu bao xa.

Trn Quang c - Lp T2 - K46 Trang

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H thng tng i NEAX

61E

Tt c cc chc nng vn hnh v bo dng c tin hnh t ng. Tuy nhin ngi iu hnh c th tham gia iu khin nh u cui iu hnh v bo dng (MAT Maintenance Administration Termianal). Giao tip Ngi My.

Thng tin trc tip gia nhn vin k thut v phn mm h thng thc hin qua MAT nh vo cc bn tin vo ra. Cc MAT thng thng c lp t ngay trong phong tng i. MAT cng c th c lp t ngay ti trung tm tr gip iu hnh v iu khin t xa qua h thng truyn dn. Cu trc phn cng ca h thng c chia thnh 4 h thng chuyn mn ho: 1. Phn h ng dng (Application Subsysem). 2. Phn h chuyn mch (Switching Subsysem). 3. Phn h x l (Processor Subsysem). 4. Phn h khai thc v bo dng ( Operation & Maitenance Subsysem). Nhng phn h ny c lp t trong cc gi my khc nhau, vi cu trc Module nh vy, khi thay i cu hnh th tng i c th c ng dng cho cc chc nng chuyn mch khc nhau nh tng i Local, Toll, tng i kt hp Toll v Local, tng i ca Quc t. Cng nh phn cng, phn mm tng ng c s dng v chng cng c cu trc Module nng. Cc im ln nht ca h thng trong cu hnh l c iu khin theo chc nng. Trong cu trc ny, i khi cn c gi l cu trc n, dng chc nng chia ti h thng n gin ho h thng va s dng nh cc kiu Module. Cc module lm vic tng i c lp vi nhau v lin h vi nhau qua cc giao din chun x l chc nng chuyn mch. Phn mm h thng c vit bng ngn ng Assembly v ngn ng PL/C (Programming Language Communication Ngn ng lp trnh thng tin). Cu hnh c bn ca h thng c chia lm 3 vng v c ct gi trong b nh ca h thng nh sau: - File h thng. - File d liu ca trm. - File s liu thu bo.

Trn Quang c - Lp T2 - K46 Trang

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H thng tng i NEAX

61EK thut chng trnh c cu trc em li hiu qu cao v tnh Logic, qu trnh x l c thc hin n gin hn. Tt c cc hot ngc a phn mm h thng c chia thnh cc Module theo chc nng. Chc nng iu khin chuyn mch c chia thnh cc chc nng ph thuc vo phn cng hoc h thng bo hiu, v d nh chc nng iu khin mng v chc nng x l logic, ieu khin v phn tich trng thi cuc gi. Do cu trc ca h thng dng Module v x l phn b bng phn mm iu khin h thng, lm cho gi thnh bp nh v vi x l c gim xung, trong khi vn c h thng chuyn mch ng tin cy. ng thi, cu hnh a x l cho php kch thc h thng c ph hp vi mi chu cu m khng lng ph dung lng khi ci t. Hn na, tnh linh hot ca phn mm v phn cng to ra h thng d dng m rng v s pht trin t c cc yu cu trong tng lai. Sau y ta s i su phn tch cu hnh c bn phn cng v phn mm ca h thng tng i NEAX 61E.

Trn Quang c - Lp T2 - K46 Trang

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H thng tng i NEAX

61E

PHN II CU HNH H THNGCHNGI. CU HNH PHN CNG.H thng bao gm 4 phn h chnh: - Phn h ng dng ( Aplications Subsytem) - Phn h chuyn mch ( Switching Subsytem) - Phn h x l ( Processor Subsytem) - Phn h vn hnh v bo dng ( O and M Subsystem)Application SubsystemTerminal Circuit Interface Circuit P M U X S M U X

Switching SubsystemTDNW TDNW

TSW

SSW

CTL

S M U X

TSW SPC

MM

CLP

MM

CLP

DKU

MTU

MAT

Test and Supervisory Console

BC

OMP High Intergrated Bus

MM CM

O&M Subsystem

Processor Subsystem

Hnh 2:Cu hnh c bn ca h thng NEAX 61E

Trn Quang c - Lp T2 - K46 Trang

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H thng tng i NEAXB iu khin Bus B nh chung n v a. B dn knh ca bng t. B ghp knh s cp. B iu khin tuyn thoi. Mng phn chia thi gian. B x l gi. B iu khin. B nh chnh.

61EBC : Bus Controller CM : Common Memory DKU : Disk Unit MTU : Magnetic Tape Unit PMUX : Primary Multiplexer SPC : Speech Path Controller TDNW : Time Division Network CLP : Call Processor CTL : Controller MM : Main Memory

OMP : Operation & Maintenance B x l vn hnh v bo dng. Processer SMUX : Secondary multiplexer SW : Space Switch TSW : Time Switch MAT : Maintenance B ghp knh th cp. B chuyn mch khng gian. B chuyn mch thi gian. & Thit b bo dng v qun l.

Administration Terminal Phn h ng dng c cu hnh p ng cc yu cu khch hng, cung cp mt giao din chun gia mng in thoi v cc phn h chuyn mch v x l.. Cc giao din dch v ny c nhim v gi thng tin qut n b x l cuc gi trong qu trnh thit lp cho cuc gi. Phn h ny c th c sa i hoc thay th p ng cc tin b k thut hoc s thay i cc yu cu ngi s dng. Phn h chuyn mch ni cc knh chuyn mch vo vi cc knh chuyn mch ra cung cp cc ng dn thoi cho cc cuc gi gia cc thu bao, gia Trn Quang c - Lp T2 - K46 Trang 8

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H thng tng i NEAX

61Ethu bao v trung k hoc gia cc trung k. Phn h ny bao gm cc mng phn chia thi gian kp cung cp ch tiu cao v s m rng h thng d dng p ng cc nhu cu tng lu lng. Phn h x l iu khin x l cuc gi, cc cng vic khai thc v bo dng, v cc chc nng bo hiu knh chung. Phn h khai thc v bo dng cung cp thng tin ngi-my cho php cc lnh ly s liu ra cho cc chc nng bo dng v qun l hng ngy.N cng cung cp kh nng gim st h thng v kim tra trung k v ng thu bao m bo cho s hot ng h thng bnh thng. Phn h ny bao gm cc thit b vo/ra khc nhau thc hin kim tra h thng v thu trng thi h thng v thng tin cnh bo.

A. PHN H NG DNG: Trn Quang c - Lp T2 - K46 Trang

9

n tt nghipAnalog Subscriber Line InterfaceAnalog Line CircuitTelephone

H thng tng i NEAXAnalog Trunk InterfaceAnalog Trunk Circuit To TDNW

61ED L S W P M U X M U S P M U X

Analog Line CircuitTelephone

To Distant Office Via Analog Lines

Analog Trunk Circuit

Controller

Controller

Digital Trunk InterfaceDigital Transmission Interface Circuit

Remote System InterfaceDigital Transmission Interface Circuit

To Distant Office Via PCM Transmition

Digital Transmission Interface Circuit

P M U X

To TDNW

To Remote System Via PCM Lines

Digital Transmission Interface Circuit

P M U X

Controller

Controller

Operator Position InterfacePosition Trunk Circuit To Operator Position Position Trunk Circuit

M U X

P M U X

Application Subsysytem

Switching Subsysytem

O&M

Controller

Subsysytem

Processor Subsysytem

Hnh 3: Cu hnh ca phn h ng dng. DLSW : Digital Line Switch PCM : Pulse Code Modulation Chuyn mch ng dy s. iu ch xung m.

Phn h ng dng cung cp mt giao tip chun gia h thng chuyn mch vi ng thu bao, ng trung k s hoc trung k analog. Trong phn h ny c cu hnh c bit phc v cc yu cu ca khch hng, gm c mt vi kiu giao Trn Quang c - Lp T2 - K46 Trang 10

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H thng tng i NEAX

61Etip phc v iu khin chc nng thay i u cui v cc mch giao tip vi phn h chuyn mch. Phn h ny c th d dng thay i hoc thay th cc k thut mi m ngi s dng yu cu. Giao tip gia phn h ng dng vi phn h chuyn mch qua mch ghp tn hiu gi qua 128 knh vi tc 8,192Mbit/s. Chc nng ca phn h ng dng bao gm: - Giao tip thu bao tng t (Line Module). - Giao tip trung k tng t (Trunk Module). - Giao tip truyn dn s (Digital Trunk Interface Module). - Giao tip bo hiu knh chung (Common Chanel Signalling Interface). - Giao tip trung k phc v (SVTM). - Giao tip kt ni ISDN. - Giao tip vi v tr bn PO (Operator Position Interface). Sau ay ta xt vi 3 loi giao tip in hnh: - Giao tip vi ng dy thu bao tng t. - Giao tip vi trung k tng t. - Giao tip vi trung k s. I. GIAO TIP NG DY THU BAO TNG T (ANALOG SUBSCRIBER LINE INTERFACE). Chc nng ny c thc hin bi khi ng dy (Line Modul ML) v b iu khin vng (Local Contronller LOC). Modul ng dy LM bao gm mch in ng dy (Line Circuit LC) v b chuyn mch chuyn mch ng dy s (Digital Line Switch). Mi mt Modul LM c th c 8 Card CL (i vi loi giao tip 64 thu bao) hoc 12 Card LC (loi giao tip 96 thu bao) hoc 16 Card LC (vi 128 thu bao). ng dng cng ngh IC nn Card c 4 hoc 8 mch LC. Modul LM gim st v iu khin LC, thc hin tp trung phn theo thi gian cho cc ng dy thu bao tng t. LM iu khin cc b phn phi bo hiu (Signalling Distributor SD) ca cc LC, kim tra o th di s iu khin ca Trn Quang c - Lp T2 - K46 Trang 11

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H thng tng i NEAX

61Eb iu khin vng LOC v t chun on li (li E/G, cnh bo ngun, trn TF . . .). Cc tn hiu (cc tuyn PCM) sau khi ra khi cc LC s c tp trung li bi b chuyn mch ng dy s DLSW to thnh mt ng SubHingWay SHW 120 knh thoi, T s tp trung c th thay i t 1,6: 1 8,5: 1 ph thuc vo s lng cc LM kt ni vi 1 SHW. LM c ni n mt LOC kp (Redundancy Config) thng qua Bus kp. LOC kim tra lin tc cc LM dm bo cho h thng hot ng bnh thng. Phn mm c s kim tra 3 ln trong khong thi gian 128ms, nu pht hi ra li, n s bo v LOC trong vng 2ms. B iu khin vng LOC nhn cc lnh iu khin gi cc tn hiu tr li v thng tin bo dng v SPC thng qua cc tuyn SHW. Analog Subsscriber Line n Interface LM LC LC LC

LOC120 Knh TDNW SPC CLP

D L S W

P M U X

Micro Processor

Hnh4: S khi mch giao tip thu bao tng t. LSC LC LM SPC CLP LOC : B chuyn mch ng dy s. : Mch in ng dy. : Modul ng dy. : B iu khin tuyn thoi. : B x l gi. : B iu khin vng. : Tn hiu s. Mch giao tip thu bao tng t thc hin 7 chc nng (BORSCHT) nh sau: Trn Quang c - Lp T2 - K46 12 Trang

TDNW : Mng chuyn mch phn chia theo thi gian.

PMUX : B ghp knh c s.

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H thng tng i NEAX

61E B : Cp ngun (Battery) : Dng b chnh lu to cc mc in p theo yu cu ph hp vi thu bao t in p xoay chiu. V d cung cp in gi cho tng my in thoi thu bao ng thi truyn tn hiu nh nhc my, xung quay s. O(Over voltage - protecting) : Bo v chng qu p cho tng i v cc thit b do ngun in p cao xut hin t ng dy nh sm st, in cng nghip hoc chp ng dy thu bao. Ngng in p bo v 75V. R : Cp chung (Ringing) : Chc nng ny c nhim v cp dng chung 25Hz, in p 75-90 Volts cho thu bao b gi. i vi my in thoi quay s dng chung ny c cung cp trc tip cho chung in c to ra m chung. Cn i vi my n phm dng tn hiu chung ny c a qua mch nn dng chung thnh dng mt chiu cp cho IC to m chung. Ti kt cui thu bao c trang b mch in xc nh khi thu bao nhc my tr li phi ct ngang dng chung gi ti trnh gy h hng cc thit b in t ca thu bao. S : Gim st (Supervisor) : Gim st thay i mch vng thu bao, x l thu bao nhn dng bt u hoc kt thc cuc gi v pht tn hiu nhc my, t my t thu bao hoc cc tn hiu pht xung quay s. C : M ho v gii m ( Code / Decode) : Chc nng ny m ho tn hiu tng t thnh tn hiu s v ngc li. H : Chuyn i 2/4 dy (Hybrid) : Chc nng chnh ca hybrid l chc nng chuyn i 2 dy t pha ng dy thu bao thnh 4 dy pha tng i. T: o th (Test) : l thit b kim tra t ng pht hin cc li nh l : ng dy thu bao b hng do ngp nc, chp mch vi ng in hay b t bng cch theo di ng dy thu bao thng xuyn c chu k. Thit b ny c ni vo ng dy bng phng php tng t kim tra v o th. Do lu lng mt thu bao thp cho nn trc khi ti trng chuyn mch th cc thu bao ni qua mt b tp trung thu bao vi t l c th c iu chnh ph hp vi lu lng. II. GIAO TIP TRUNG K TNG T (ANALOG TRUNK INTERFACE). Giao tip trung k tng t Analog hnh thnh gia cc trm Analog vi nhau. Trung k chia thnh trung k i, trung k v v trung k hai chiu tu theo yu cu ca khch hng. Cc tn hiu t mt mch trung k tng t n c chuyn thnh tn hiu PCM bi b m ho v gii m CODEC khng cn tp trung. Sau tn hiu PCM c ghp knh, b ghp knh c s (PMUX - Primary Multiplexer) ln nht l 120 knh. Giao tip trung k tng t cng c chc nng iu khin m cho nhng ng trung k c bit. H thng cng c nhng mch cho giao tip vi trm chuyn mch kt hp. Nhng mch ny c th truyn DP. MPF hoc MF cho ghi pht trn trung k. Mch giao tip trung k c nhng loi sau: Trn Quang c - Lp T2 - K46 Trang 13

n tt nghip- Trung k 2 dy (2 W) E&M. - Trung k 4 dy (4 W) E&M. - Trung k i. - Trung k v. V mt s loi khc.

H thng tng i NEAX

61E

4ATC ATC ATC

Analog Trunk Interface TM

LOC120 Knh TDNW SPC CLP

D L S W

P M U X

Micro Processor

Hnh5: Giao tip trung k tng t. LOC : B iu khin vng. ATC : Analog Trunk Ciriuit Mch in trung k tng t. MUX : B ghp knh. TM : Modul trung k. PMUX : B ghp knh c s. Mt Modul trung k TM di s iu khin ca LOC c th kt ni c 30 trung k tng t. Cc mch in u cui v mch in giao tip ca TM chnh l mch in trung k tng t TRK v b CODEC. Cc TRK c phn thnh cc thnh phn cc mch trung k gi n ICT, trung k gi i OGT v trung k hai chiu ... N x l loi bo hiu ng dy khc nhau nh bo hiu vng, xung quay s, bo hiu m a tn, bo hiu E&M. Ti a 4 TM c th u ni n 1 SHW n, Bus iu khin ca TM cng c kt ni n 4 TM ny. TM c ni n LOC thng qua cc Bus kp v hot ng di s iu khin ca ACT LOC (B iu khin vng lm vic). S trung Trn Quang c - Lp T2 - K46 14 Trang

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H thng tng i NEAX

61Ek (Trunk Number TN) c xc nh nh s ca mi knh trung k trong dng tn hiu s PCM 30/32. Mi trung k c nh ngha bng ch s HW, ch s nhm v ch s TN. Ta thy rng phn giao tip ng ay thu bao tng t, giao tip trung k tng t u c iu khin bi b iu khin vng LOC. Nh vy b iu khin ca hai phn ny u c chc nng hot ng ging nhau. Trong thc t khi iu khin vng c s dng chung. LOC c cu hnh kp gm LOC0 v LOC1, do c 8 SHW c ni n LOC v hai Card cp ngun PWR0 v PWR1. Bnh thng LOC lm vic ch ng b, nhng n cng c th lm vic ch tch bit, ch ny c dung khi chy chng trnh chun on li. LOC thc hin cc cng vic sau: - iu khin truyn tn hiu n hoc i t SPC: Nhn cc lnh iu khin LM v TM t b iu khin tuyn thoi SPC, ng thi gi cc tn hiu tr li v thng tin bo dng v SPC. - Ghp tch knh s cp: Tch knh cc tn hiu thoi t 1 SHW (128 knh) thnh 4 HW (32 knh) v ngc li ghp 4HW thnh 1 SHW. - iu khin cc mch LC v TRK theo cc lnh SD v t SPC gi n. - iu khin kim tra o th: u ni cc LC, TRK n cc b Test. - iu khin b chuyn mch ng dy s (DLSW) thc hin tp trung ng dy thu bao. - iu khin vic hn ch cuc gi i. - iu khin kim tra kt ni: LOC c mt b thu pht tn hiu kim tra kt ni hot ng theo cc lnh iu khin CONT TST. Vic kim tra kt ni c thc hin 1ln/512 cuc gi. Tn hiu kim tra c pht tn s 1kHz vi mc tn hiu l 0dB. - iu khin cp dng chung: Gi cc tn hiu iu khin cc pha cp chung n nhng b LC hoc TRK. - iu khin b thu xung quay s (Dial Pulsse Receiver DPOS): Chuyn cc xung quay s n cc trung k c xc nh theo lnh DPOS t SPC. - iu khin cc tn hiu qut: Truyn cc tn hiu qut t LM hoc TM v SPC. III. GIAO TIP TRUNG K S. Giao tip cho php truyn trc tip tuyn vi chuyn mch. Tu vo cch lp m theo lut A hoc lut ta c PCM 30 hay PCM 24 c trung k c bit trong mch giao tip truyn dn s ( Digital Transmission Iterface DTI). Ti y c 4 tuyn PCM, mi ng 30 knh (theo tiu chun A) hoc 5 ng PCM mi ng 24 knh (theo tiu chun ) s c a ti b ghp knh s cp PMUX. Nh vy s c 120 knh tn hiu do (30 x 4 hoc 24x 5) knh ghp li. Sau khi Trn Quang c - Lp T2 - K46 15 Trang

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H thng tng i NEAX

61Egiao tip trung k s tn hiu s c a ti khi chuyn mch thi gian vi 132 khe thi gian tng ng vi 120 knh thoi. Modul giao tip trung k s gm c mch giao tip truyn dn s (Digital Transmission Interface DTI), b ghp knh c s PMUX. Modul giao tip truyn dn s PCM TDM theo lut A. V pha truyn dn th n giao tip vi cc trm lp u cui ca nhm PCM 2,048Mbs (s cp) bng cc giao din truyn dn s DTI, v pha mng chuyn mch, n gioa tip thng qua cc tuyn SHW. B iu khin giao tip truyn dn s DTIC c gn trn DTIM, c nhim v iu khin cc b ghp tch knh s cp (PMUX PDMUX), iu khin cc DTI, qu trnh x l bo hiu. Modul giao tip truyn dn s gia cc h thng PCM 30/32 theo tiu chun CEPT. Modul DTIM c kt ni vi cc ng PCM s cp theo lut A (30/32 knh, tc 2048kbs). Mi DTIM c 2 b iu khin DTIC, mi DTIC iu khin 4DTI. Mi DTI c ni vi mt tuyn PCM 30/32. Mi khung truyn dn s c 16 modul DTIM, mi DTIM c th giao tip vi 8 tuyn PCM (tc l 240 knh), nh vy mt khung giao tip truyn dn c th p ng cho 3840 knh.

DTIC 120 Knh 30 Knh 4 PCM Line 30 Knh DTI 4 DTI P M U X

TDNW

MicroProcessor

SPC

DTIC 120 Knh 30 Knh 4 PCM Line 30 Knh DTI 4 DTI P M U X

CLP

MicroProcessor

Hnh 6: S giao tip trung k s. Trn Quang c - Lp T2 - K46 Trang

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H thng tng i NEAX

61EIV. GIAO TIP V TINH. Trong cu trc h chuyn mch v tinh, h thng c giao tip ng dy thu bao tng t cho cc thu bao vng xa . Cc thu bao c ni vi mng chuyn mch trm ch thng qua cc tuyn PCM. Vi s phc v cho nhng thu bao xa NEAX 61E c hai kiu ng dng l RUS (Remote Subcriber Unit) v RLU (Remote Line Unit). C hai kiu ny u c cng mt giao din. Mc ch ca giao din l ni cc thu bao xa vi trm ch thng qua tuyn PCM. Chc nng ca mch kt cui l to giao tip truyn dn s. Vi cu hnh nh vy, h thng trm ch c th x l cuc gi cho c thu bao c ni vi trm t xa hay trc tip vo trm ch. V. GIAO TIP TRUNG K DCH V. Giao tip ny cung cp dch v pht Tone v mch bo hiu AC, n bo gm nhng mch trung k dch v khc nhau chng hn b pht Tone, b thu pht bo hiu ghi pht. VI. GIAO TIP BO HIU KNH CHUNG. Giao tip bo hiu knh chung CCS thc hin chc nng bo hiu knh chung CCS gia cc tng i ph hp vi yu cu bo hiu s 7 (SS7). Giao tip ny tng thch vi ng bo hiu tc 64kbps trn ng dy s v 48kbps trn ng dy tng t. N ni h thng vi mng d liu chuyn mch cng cng (CSPN) qua modul trung k dch v (SVTM) trong phn h chuyn mch v modul giao tip truyn dn s DTIM. VII. GIAO TIP KT NI ISDN. Giao tip ng dy truy nhp c bn. Giao tip cung cp ng ni gia mng ngi s dng (U) (2B + D) ISDN n thit b nh ring ca thu bao nh thit b kt cui mng NT v b thch ng u cui (TA). Thnh phn c bn bao gm giao tip ng dy truy nhp c bn l Modul ng dy s DLM, giao tip tc c s v modul b x l iu khin ng LCPM. Modul ng dy s DLM cung cp giao din kiu U vi thu bo bi ng truy nhp c bn 2 knh B v mt knh D (2B + D). ng truy nhp c bn u cui c tp trung v ghp vo ng tc s cp 30B + D nh b x l iu khin ng LCPM. Modul x l iu khin ng PCPM ghp cc ng truy nhp tc s cp thnh ng Subhighway. ng ny ghp vi phn h chuyn mch. Trn Quang c - Lp T2 - K46 17 Trang

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61EModul x l iu khin PCPM c cc chc nng sau: - Knh thng tin D c th dng chuyn mch gi. - Giao din Logic vi Modul chuyn mch gi (PSM) gi v chuyn mch gi. - X l chc nng chuyn mch knh: + Giao tip tc s cp: Giao tip ny bao gm Modul giao tip tc s cp (PRIM) v Modul x l iu khin ng PCPM. + Giao tip mng chuyn mch gi (PNI): Giao tip mng chuyn mch gi PNI c iu khin bi b chuyn mch gi (PH), cho php cc thu bao ISDN truy nhp vi mng s liu chuyn mch gi cng cng (PSPDN) qua ng trung k X75. VIII. GIAO TIP BN PQ. Cc giao tip ch dng trong tng i Toll hoc tng i quc t. Giao tip ny ni thu bao gi hoc thu bao b gi hoc c hai loi vi ngi iu hnh thng qua mch trung k v mng chuyn mch. Nhng v khc nhau bao gm cuc gi trm ti trm hoc nhng cui gi ni thu bao ti thu bao chn lc cc cuc gi c th c ni ti bn phc v. H thng c th cung cp ti a l 512 bn PO tu thuc vo yu cu ca khch hng. B. PHN H CHUYN MCH. Chc nng chnh ca phn h chuyn mch l ni knh u vo vi knh u ra cung cp cc ng thoi cho nhng cuc gi gia cc thu bao, gia thu bao v nhng trung k hoc gia trung k . H thng s dng mt mng chuyn mch n trong cu trc Buiding Bock to mt lng ln cc dung lng chuyn mch. Mt h a x l, c th to c 22 module chuyn mch nh cung cp chc nng chuyn mch cho 100.000 thu bao. Mi mng chuyn mch (vi cu hnh a x l) c 4 tng chuyn mch T S S T, mi h thng c x l cuc gi iu khin. S la chn cu trc ny cho php h thng c kh nng m rng ln nht.

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H thng tng i NEAXSHW

61ES M U X S M U X128 Time Slotsx4=512 Time Slots HW JHW Time Switch (T1) Space (6) Switch (S1) Time Switch (T1) HW Time Switch (T2) S D M U X

480CHx6 =2880CH

Space Switch (S2)

(6)Time Switch (T2) S D M U X

6x24

24x6

67,584 time slots S M U X2880CH

22

22

67,584 time slotsTime Switch (T2) S D M U X

Time Switch (T1)

(6) S M U XTime Switch (T1)

Space Switch (S1)

Space Switch (S2)

(6)Time Switch (T2) S D M U X

6x24

24x6

SPC

To/From Call Processor

Application Subsysytem

Switching Subsysytem

Processor Subsysytem

O&M Subsysytem

Hnh 7: Cu trc trng chuyn mch NEAX 61E. Trng chuyn mch ca h thng tng i NEAX 61E c cu trc T-S-ST, mi mng chuyn mch c s bao gm 6 b chuyn mch thi gian s cp (T1), mt b chuyn mch khng gian s cp (S1), mt b chuyn mch khng gian th cp (S2) v 6 b chuyn mch thi gian th cp (T2). Phn h chuyn mch giao tip vi phn h ng dng c thc hin qua b ghp knh s cp (SMUX) v b phn knh th cp (SDMUX). Mi SMUX v SDMUX c ni vi T1 v T2. Tn hiu PCM gi qua SHW co 128 khe thi gian tc l 120 knh thoi a vo SMUX. Mi SMUX phc v cho 4 ng SHW u vo, u ra l ng HW vi 512 khe thi gian. Ti T1 nhng t PCM truyn qua Trn Quang c - Lp T2 - K46 Trang

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61Eng HW c vit mt cch tun t vo nh tng ng v c ra ngu nhin vo khe thi gian ra theo lnh iu khin ca phn mm, t b ng ting (SPC). Ti u ra ti S1, T1 chuyn dng tc 8.448Mb/s (8 bit ni tip) sang dng s tc 4.224Mb/s (4 bt song song). Sau cc khe thi gian c phn u ti mt trong 24 ng JHW tu theo lnh t SPC. S1 l ma trn chuyn mch 6 x 24 v mt trong 24 u ra c ni vi mt ng JHW (Junctor High Way). S2 l ma trn chuyn mch 24 x 6 v truyn mi khe thi gian ti mt trong 6 ng HW. SDMUX tch 512 khe thi gian ca ng HW t T2 thnh 4 ng SHW. Lc ny dong bt 4.224Mb/s c bin i thnh dng 8.448Mb/s. Mi mng chuyn mch c 6 ng HW ny c theer chuyn 2.880 knh. Vi s lng ln nht l 22 nhng mng chuyn mch ny ni bng cc ng JHW c iu khin bi mt SPC. Phn chuyn mch c cu trc kp h thng c an ton cao. Mi mng chuyn mch c kh nng ghp l 2.880 cng chuyn mch, mi mng chuyn mch gm c 6 x 24 cng chuyn mch khng gian u ra. C th kt ni ln nht 22 mng chuyn mch v phn h chuyn mch vi kh nng lu thot lu lng ln nht l 27.00 Erlangs. H thng chuyn mch v mt vt l c gn trn khung chuyn mch thi gian v x l cuc gi (TSCPF). Mi b TSCPF gm c 5 loi Module chnh nh sau: - Modul tuyn thoi (Spech Path module SPM). - Module iu khin ng thoi (Spech path Controller - PM). - Module x l iu khin (Controll Process Module CPM). - Module trung k dch v (Service Trunk Module SVTM). - Module ng h (Clook Module - CLKM). SPM l mt b thit b dng thit lp cc tuyn thoi trong h thng. SPM c hai khi chc nng chnh l chuyn mch theo thi gian TSW (Time Switch) c b chuyn mch theo khng gian SSW (Space Switch), ngoi ra n cn gm c cc b giao tip vi b iu khin tuyn thoi, b iu khin khai thc v bo dng, b thu tn hiu ng h. SPM thc hin chc nng x l cc chuyn mch theo thi gian, chuyn mch theo khng gian kt ni cc tuyn thoi gia cc thu bao. Ngoi ra module SPM cn thc hin cc chc nng sau: Trn Quang c - Lp T2 - K46 Trang 20

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H thng tng i NEAX

61E- B s sai pha gia cc tn hiu s c truyn i t LOC. - Ghp knh 4 tuyn SHW to ra mt tuyn HW (hng thu). - Truyn cc lnh iu khin do LOC, DTIC, SVTC gi v SPC. - Thc hin cc thao tc chuyn mch theo thi gian v theo khng gian. - Tch 1 tuyn HW thnh 4 tuyn SHW (hng pht). - Nhn cc lnh iu khin t SPC a n LOC, DTIC. - Thc hin chun on li. Mi modul SPC u c cu trc kp, mt module SPC c th iu khin ti a 6 ng HW (490 x 6 = 2.880 knh thoi), n thc hin cc chc nng sau: - Giao tip vi module x l v iu khin (CPM). - Chim gi v phn b thng tin cu thnh ng thoi. - Tp trung cc thng tin li v thng tin bo dng ca h thng chuyn mch v thng bo n CPM. - Phn phi xung ng h v xung ng b a khung t module ng h ti thit b chuyn mch. - Pht hin ng dy ch gi, ct u ni hay tn hiu tr li v thng bo n PCM. - Nhn thng tin a ch t cc b iu khin ng dng. - Cung cp giao tip tn hiu iu khin gia module PCM v module TSM, SSM hay SPM. - Thc hin qu trnh chun on li. Module ng h c nhim v to ra 3 loi ng h chun v cc xung ng b a khung MFP cho tng i l: - 8,448 MHz v MFP. - 8,912 MHz v MFP. - 6,172 MHz v MFP. Module ng h c cu hnh kp (CLKM0 v CLKM1). Mi module ng h cp cho 12 b SPC, mi module ng h s cp v m rng cp cho ti a 22 SPC, CLKM c s iu khin bng CMP (OMP) trong h thng x l vn hnh v Trn Quang c - Lp T2 - K46 Trang 21

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H thng tng i NEAX

61Ebo dng. Bnh thng module ng h ca tng i hot ng ch phc hi t ng chn tuyn tham chiu, nhng cng c th phc hi bng nhn cng nh lnh hoc kho chuyn.

C. PHN H X L. H thng a x l ca tng i NEAX 61E l mt h thng x l c cu trc theo tng module chc nng nh phn x l iu khin qu trnh x l cuc gi v cc cng vic khai thc bo dng, iu hnh, x l gi, bo hiu knh chung c thc hin bi cc b x l iu khin ring bit CP (Control Processors). Mi b x l cho mt chc nng c t tn ty theo chc nng thc hin nh Call processor. Nhng c tnh ca cu trc a x l: - Chuyn mch iu khin theo chng trnh ghi sn SPC. - Kiu cu trc khi trn c s module phn cng v phn mm chc nng v giao din tiu chun. - iu khin a x l theo phng thc phn b vi h thng dung lng ln v phng thc tp chung cho cc h thng c dung lng va v nh m bo h thng c tin cy cao. - H thng chuyn mch T - S S T hu nh khng tc nghn ny mi module c th chuyn mch 2880 knh thng tin. - Cng ngh mch tin tin tin mt cao VLSI. - C cc chc nng t chun on ti tng phn cng cng nh tng ng dy. - T ng bo v d liu nh cp nht thng xuyn d liu vo bng t v a. - Phn h chuyn mch v phn h ng dng ring bit vi giao din chun ho. - T chc cc tuyn, ng s liu xut cao nn kh nng mt mt tn hiu trong truyn dn gim xung t nht. Cu hnh ph hp vi tiu chun ca CCITT. Trn Quang c - Lp T2 - K46 Trang 22

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H thng tng i NEAX

61ETrong cu trc a x l, phn h x l c th gm ti 32 b iu khin x l CP trong c 22 b x l cuc gi CLP (Call Processor), b x l iu khin nh v PCP (Position Control Processor) v mt b x l cuc gi CLP thc hin chc nng x l cuc gi theo ch phn chia ti. B x l khai thc v bo dng bao gm s thng tin Ngi Myv iu khin cc tuyn bo dng v iu khin nhng CPS cho vic kim tra hoc iu khin truy nhp nhng module ring. Thng tin gia nhng CP c thc hin thng qua h thng BUS, c iu khin bi mt b iu khin BUS BC (Bus Controller). Mi b x l cuc gi (LCP) c cu trc kp iu khin mt mng chuyn mch. B iu khin chuyn mch thng tin vi cc CLP ca chng qua SPI (Speech Path Interface). S liu trao i gia cc b x l cuc gi CLP c thc hin bi b x l Bus h thng SBP (System Bus Processor) thng qua Bus tch hp cao. Mi CLP c b nh ring nh chng trnh, d liu ni b v d liu nhng vng tm thi.

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H thng tng i NEAXT o/From SPC or PSC Up to 32 CPMs (22 CLPs and other)

61ESPICPM (CP)

SSPT o/From MPC

CC

MMCMADP(31) T o/From CMIM

SBP BC SBP SPICPM (OMP) SB

CPM

T o/From CMADP

SSP

CC

MM CMAD CMADP P

(8) (4)

(8)

CMIM

CMIM

SPIT o/From T ST MSPB

IOP CMM

HIB (T o/F rom O&M Subsystem)

T o/From SSP 16 16

T o/From MCSL

MPC

MPC

Hnh 8: S khi h thng a x l. BC CLP : Bus Contronler : Call Processor MM : Main Memory

MPC : Multiprocessor Contronler SB SBP SPC SPC SPI : System Bus : System Bus Processor : Speech Path Bus : Speech Path Contronler : Speech Path Interface

CMADP : Common Memmory Adater CMM CPM CPU IOP : Common Memmory Module : Control Processor Module : Central Processor Unit : Input/Output Pro

Phn chnh ca phn h x l m module x l iu khin CPM (Control Processor Modul). Modul iu khin x l CPM gm cc khi chc nng: n v x l trung tm (CPU). X l dch v h thng (SSP). Trn Quang c - Lp T2 - K46 Trang 24

n tt nghip B nh chnh (MM). Tip hp b nh chung (CMADP). B x l Bus h thng (SBP). Giao tip ng thoi (SPI). X l vo ra (IOP).

H thng tng i NEAX

61E

I.N V X K TRUNG TM (CENTER PROCESSING UNIT CPU). Khi ny thc hin vic vic c v thc thi cc chng trnh cn thit cho hot ng chuyn mch trong h thng. Khi iu khin trung tm c cu to ko l CPUA v CPUB, mt b chuyn i Bus BSC (Bus Converter) v mt b iu khin cho ngang cp MXC (Mate cross Controlles). Mc d ch cn mt CPU cho thc hin hot ng ca h thng nhng n vn c trang b kp m bo tin cy. Tuy nhin CPUA v CPUB lun hot ng ng b vi nhau v mi v thc hin mt chc nng thit yu. CPU dng trong h thng l Model 101 (S560000/101). CPU c chng trnh t b nh chnh (MM), gii m cu lnh v thc hin chng ph hp vi cc chc nng yu cu. Card CPU cng bao gm mt b nh vng LS (Local Storage) vi dung lng 64kiloword trong b nh. B nh LS cha mt cch ln lt cc chng trnh, s liu c s dng v cho php mt s gia tng tc truy nhp vi chng. S liu iu khin c gi ti nhng b iu khin trong phn ng dng v trong phn chuyn mch hoc ti b iu khin vo ra (IO) trong phn iu hnh v bo dng. B chuyn i Bus (BCS) chuyn i th tc gia Bus b nh (M Bus) v Bus trung tm (C Bus). MXC iu khin truy nhp b nh theo lp to bi hai hng iu hnh vo v ra. II. B NH CHNH (MAIN MEMORY MM). Nhp ch th t CPU thc hin vit vo hay c ra t b nh ca chng. Mt MM cha 4 Megawords trn Card v dng 32 bits, trong c bt l m kim tra. Mt Card MM c sp xp 160 MOS Ram ng (1 megabit). Theo l thuyt mi CPU c th iu khin ti 64megaword b nh vt l CPM c 2MM v 2 megaword ph trong MXC Card. V vy, tng dung lng ln nht ti 10 megaword. III. B X L BUS H THNG (SYSTEM BUS PROCESSOR SBP).

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H thng tng i NEAX

61EThng qua cc Bus truyn s liu di s diu khin ca CPU lin quan, b SBP s thc hin truyn s liu gia CPM. Speechn Path Interface (SP1) iu khin s truyn dn s liu OPM nhng Module kim tra trong phn iu hnh v bo dng thng qua Specth Bus. IV. H THNG X L DCH V (SYSTEM BUS PROCESSOR SSP). SSP l phn giao tip gia CPU v b iu khin a x l MPC (Multiproccer Controler) ng thi cung cp tnh trng h thng. Khi SSP c iu khin bi Master Console (MCSL) thng qua nhng cu lnh iu hnh nhn cng. Khi ny cng cha cc mch bo ng khn cp EMA (Emergeny Action) hot ng do thit b theo di tnh trng khn cp. Khi CMADP cung cp mt giao tip cho CPM vi b nh chung. Khi CMADP c ni vi CMM qua CNIM. Khi IOP iu khin truyn d liu gia MM v thit b vo/ra. D. PHN H KHAI THC V BO DNG.TASS (ASC) (CSC) (SUPC) ATME To Application Subsytem

CQDP VER

MC

ALDISP STCTo Application Subsytem

OMP MTCRemote Maintece Center

TC ISACC MD

TC

DKC DKC

MTC DKC

LPC LP

MPC

ISACC MD

MAT

MSCL

Phn h khai thc v bo dng cung cp thng tin ngi - my nh cc cu lnh v s liu a vo phuc v cng vic bo dng v qun l h thng. N cng cung cp kh nng gim st, kim tra h thng chng hn nh kim tra s hot ng ca ng trung k v thu bao, m bo s hot ng bnh thng ca h thng. Phn h ny gm nhiu loi thit b vo v ra khc nhau, qua cc nhn vin khai thc v bo dng c th kim tra chi tit trng thi cng nh cc cnh bo ca h thng. Ngoi ra n cn c tnh t ng ho cao, mi mt OPM thng Trn Quang c - Lp T2 - K46 26 Trang

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H thng tng i NEAX

61Exuyn thc hin trc tip v ngm nh nhng chu k bo dng theo yu cu. Thit b vo ra c ni vi OPM cho php h thng d dang khai thc v bo dng. Thit b vo ra cng c th gm c c u cui bo dng v gim st (MAT), khi bng t (MTU), a (DKU) v ng ni my in (LP). Mi b iu khin thng tin c th c thm vo giao tip v thng tin vi trung tm iu hnh v bo dng. Cc khi LTC, STC, MCSL, ALDISP v DATS cung cp thng xuyn cho tuyn thu bao v trung k qu trnh o v kim tra bo dng. Cc thng bo v tnh trng ca phn cng v phn mm hin trn ALDISP. H thng ny hin th kt qu tm li v phn tch cc chng trnh ti MAT v c th nhanh chng cch ly thit b c li. Qu trnh kim tra trung k c thc hin t STC (System Test Console) v cng dng cho bo dng xa. Vi phn ng dng ca tng i quc t, SDC (dch v quan st ngoi vi), NWM (qun l my) terminal v u cui hin th tnh trng ca cc tuyn (RTS) nn c ci t thm. Vic qun l v khai thc ca NEAX 61E c thc hin bi nhn vin khai thc, nh s la chn cc lnh tng ng. Cc lnh ny c a vo thng qua h thng vo ra c th l MAT (Maintemance Administration Manualterminal). MAT l mt phn ca h thng khai thc v bo dng. Thng qua ngi s dng c th thc hin nhiu chc nng khai thc (v du: cc thue tc kim tra h thng), ni chnh xc hn MAT l giao din gia ngi s dng v h thng. Cc lnh c ngi s dng a vo s c x l, ng thi h thng s a ra bn tin p ng lnh. H thng cung cp mt tp a dng cc lnh s dng vi mc ch v ngha ring ca n. - Nhm lnh bao gm: L nhm lnh ma thng qua ngi s dng c th thay i c thuc tnh ca c h thng, m rng h thng, m cc tuyn trung k, qun l cc tuyn trung k . . .in hnh ca nhm lnh ny l lnh ODC: Office Data Change). - Nhm cc lnh c bit: in hnh ca nhm lnh ny l lnh MLD (Memory Load np b nh). Lnh ny c dng vi mc ch c bit, ch c dng di s ng ca nh sn xut. V nhng lnh ny thng cung cp s liu cho nh qun l c nhim v vo s liu . Trn Quang c - Lp T2 - K46 Trang 27

n tt nghip

H thng tng i NEAX

61ENgi lp lnhh thng cn cung cp cc kh nng kim tra gim st h thng bng cc thit b ph tr khc. V d nh STC: System Test Consol), h thng gim st cnh bo nhm sm pht hin cc trng thi cnh bo. Khun dng lnh vo v cc bn tin p ng h thng: + Khun dng lnh vo: Tt c cc lnh c nap vo qua h thn MAT, dng lnh vo nh sau: