tim hieu trien khai lap dat mang truy nhap quang ftth

7/28/2019 Tim Hieu Trien Khai Lap Dat Mang Truy Nhap Quang FTTH

1/33


2/33

AON c nhiu u im nh tm ko dy xa (ln n 70km m khng cn b

lp (repeater) , tnh bo mt cao (do vic can thip nghe ln trn ng truyn gn nh

l khng th ), d dng nng cp bng thng thu bao khi cn , d xc nh li ... Tuy

nhin , cng ngh AON cng c khuyt im l chi ph cao do vic vn hnh cc thit

b trn ng truyn u cn ngun cung cp , mi thu bao l mt si quang ring ,

cn nhiu khng gian cha cp . Ngoi m hnh trn , trong thc t ty vo nhu cu

bng thng thu bao , cc nh cung cp cng kt hp cp quang vi cp ng gim

chi ph , c th nh cp quang chy t Access Node ti tng i DSLAM v t

DSLAM cung cp cc dch v truy cp bng thng ph bin nh ADSL2+ , VDSL2..

1.2 Mng quang th ng PON :

Hnh 1.2: mng quang th ng PON

PON (Passive Optical Network ) l kin trc mng im - nhiu im .

gim chi ph trn mi thu bao, ng truyn chnh s i t thit trung tm OLT

(Optical Line Termination ) qua mt thit b chia tn hiu (Splitter) v t thit b ny

mi ko n nhiu ngi dng (c th chia t 32- 64 thu bao). Splitter khng cn

ngun cung cp, c th t bt k u nn nu trin khai cho nhiu thu bao th chi

ph gim ng k so vi AON. Do Splitter khng cn ngun nn h thng cng tit


3/33

kim in hn v khng gian cha cp cng t hn so vi AON. Kiu mng PON

thng gp hin nay l: Ethernet-PON(EPON), Giga-Ethernet-PON(GEPON),

Gigabit-PON(GPON)Cc cng ngh ny u da trn chun IEEE 802.3

Ethernet.

Chun GPON hin ti t ti tc download 2.5Gbps v upload 1.25Gbps

ln mng core.Tuy nhin PON cng c nhiu khuyt im nh kh nng cp bng

thng khi thu bao yu cu (do kin trc im n nhiu im s nh hng n

nhng thu bao khc trong trng hp dng ht bng thng ) , kh xc nh li

hn do 1 si quang chung cho nhiu ngi dng , tnh bo mt cng khng caobng AON

1.3 Cc chun trong mng PON:

1.3.1 Nhm truy nhp TDMA-PON:

Cc chun mng PON c th chia thnh 2 nhm: nhm 1 bao gm cc chun

theo phng thc truy nhp TDMA-PON nh l B-PON (Broadband PON), E-

PON (Ethernet PON), G-PON (Gigabit PON) (c tnh cc ca chun TDMA-PON

c so snh trong Bng 1.1); nhm 2 bao gm chun theo cc phng thc truy

nhp khc nh WDM-PON (Wavelength Division Multiplexing PON) v CDMA-

PON (Code Division Multiple Access PON).

Mng quang th ng bng rng B-PON c chun ha trong chui cc

khuyn ngh G.938 ca ITU-T. Cc khuyn ngh ny a ra cc tiu chun v cc

khi chc nng ONT v OLT, khun dng v tc khung ca lung d liu hng

ln v hng xung, giao thc truy nhp hng ln TDMA, cc giao tip vt l, cc

giao tip qun l v iu khin ONT v DBA.

E-PON l giao thc mng truy nhp y dch v FSAN (Full Service

Access Network) TDMA PON th nht c pht trin da trn khai thc cc u

im ca cng ngh Ethernet ng dng trong thng tin quang. E-PON c chun


4/33

ha bi IEEE 802.3.G-PON l giao thc FSAN TDMA PON th 2 c nh ngha trong

chui khuyn ngh G.984 ca ITU-T. G-PON c xy dng trn tri nghim ca

B-PON v E-PON. Mc d G-PON h tr truyn ti tin ATM, nhng n cng a

vo mt c ch thch nghi ti tin mi m c ti u ha cho truyn ti cc khung

Ethernet c gi l phng thc ng gi G-PON (GEM GPON Encapsulation

Method).

GEM l phng thc da trn th tc ng khung chung trong khuyn ngh

G.701 ngoi tr vic GEM ti u ha t mo u phc v cho ng dng ca

PON, cho php sp xp cc d liu Ethernet vo ti tin GEM v h tr sp xp

TDM.

Bng 1.3 So snh cc chun cng ngh TDMA PON


5/33

1.3. 2 WDM-PON :WDM-PON l mng quang th ng s dng phng thc a ghp knh

phn chia theo bc sng. OLT s dng mt bc sng ring r thng tin vimi ONT theo dng im-im. Mi mt ONU c mt b lc quang la chn

bc sng tng thch vi n, OLT cng c mt b lc cho mi ONU.

Nhiu phng thc khc c tm hiu to ra cc bc sng ONU nh

l:

- S dng cc khi quang c th lp t ti ch la chn cc bc sng ONU

- Dng cc laser iu chnh c.

- Ct ph tn hiu.

- Cc phng thc th ng m theo OLT cung cp tn hiu sng mang

ti cc ONU.

- S dng tn hiu hng xung iu chnh bc sng u ra ca laser

ONU.

Cu trc ca WDM-PON c m t nh trong Hnh 3.2.1.2. Trong

WDM-PON c th c s dng cho nhiu ng dng khc nhau nh l FTTH, cc

ng dng VDSL v cc im truy nhp v tuyn t xa. Cc b thu WDM-PON s

dng k thut lc quang mng ng dn sng AWG (Array Waveguide Grating).

Mt AWG c th c t mi trng trong nh hoc ngoi tri.


6/33

Hnh 1.4: Cu trc ca WDM-PON

u im chnh ca WDM-PON l n kh nng cung cp cc dch v d liu

theo cc cu trc khc nhau (DS1/E1/DS3, 10/100/1000 Base Ethernet) ty theo

yu cu v bng thng ca khch hng. Tuy nhin, nhc im chnh ca WDM-

PON l chi ph kh ln cho cc linh kin quang sn xut b lc nhng bc

sng khc nhau. WDM-PON cng c trin khai kt hp vi cc giao thc TDMA

PON ci thin bng thng truyn tin.

1.3.3 CDMA-PON:

Cng ngh a truy nhp phn chia theo m CDMA cng c th trin khai

trong cc ng dng PON. Cng ging nh WDM-PON, CMDA-PON cho php mi

ONU s dng khun dng v tc d liu khc nhau tng ng vi cc nhu cu


7/33

ca khch hng. CDMA-PON cng c th kt hp vi WDM tng dung lng

bng thng.

CDMA-PON truyn ti cc tn hiu khch hng vi nhiu ph tn truyn dn

tri trn cng mt knh thng tin. Cc k hiu t cc tn hiu khc nhau c m

ha v nhn dng thng qua b gii m. Phn ln cng ngh ng dng trong

CDMA-PON tun theo phng thc tri ph chui trc tip. Trong phng thc

ny mi k hiu 0, 1 (tng ng vi mi tn hiu) c m ha thnh chui k t

di hn v c tc cao hn. Mi ONU s dng tr s chui khc nhau cho k t

ca n. khi phc li d

liu, OLT chia nh tn hiu quang thu c sau gi ti cc b lc nhiu x

tch ly tn hiu ca mi OUN.

u im chnh ca CDMA-PON l cho php truyn ti lu lng cao v c

tnhnng bo mt ni tri so cc chun PON khc. Tuy nhin, mt tr ngi ln

trong CDMA-PON l cc b khuch i quang i hi phi c thit k sao cho

m bo tng ng vi t s tn hiu/tp m. Vi h thng CDMA-PON khng c

b khuch i quang th ty thuc vo tn hao b sung trong cc b chia, b xoay

vng, cc b lc m h s t chia ONU/OLT ch l 1:2 hoc 1:8. Trong khi vi

b khuych i quang h s ny c th t 1:32 hoc cao hn. Bn cnh cc b

thu tn hiu trong CDMA-PON l kh phc tp v gi thnh tng i cao. Chnh v

nhng nhc im ny nn hin ti CDMA-PON cha c pht trin rng ri.


8/33


9/33

CHNG 2:TM HIU TNG QUAN V MNG TRUY NHP QUANG

FTTX

2.1 Gii thiu chungFTTx (Fiber to the x) l mt thut ng chung cho bt k kin trc mng bng rng

s dng cp quang thay th tt c hay mt phn cp kim loi thng thng dng trong

mch vng chng cui ca mng vin thng.Thut ng chung ny bt ngun nh mt

s tng qut ha mt vi m hnh mng trin khai si quang (FTTN, FTTC, FTTB,

FTTH, FTTP),tt c bt u bng FTT nhng kt thc bi cc k t khc nhau, c

thay th bng x mang tnh cht tng qut ha.

Ngnh cng nghip vin thng phn bit mt vi m hnh ring bit, r rng.

Trong c s dng rng ri nht hin nay l:

Fiber To The Home (FTTH): si quang c dn ti ranh gii khng gian

sng, nh mt hp cp quang c t trn tng bn ngoi ca mt ngi

nh.

Fiber To The Building (FTTB): si quang c dn ti chn ca mt ta

nh cao tng, t thng qua phng tin chuyn i (quang-in) u

ni ti tng ngi s dng ring bit.

Fiber To The Curb (FTTC): si quang c dn ti t cp t trn l

ng cch khu vc khch hng gn hn 300m,t s dng cp ng

u ni ti ngi dng.

Fiber To The Node (FTTN): si quang c dn ti node, n cng tng

t nh FTTC, nhng khong cch t node ti khu vc khch hng th xahn, c th ti vi kilomet.

9


10/33

Hnh 2.1: cc m hnh FTTx

Nhu cu s dng h tng cp quang ti h gia nh FTTH (Fiber to the Home) xut

hin t nhng nm 1980 khi m cc cng ty in thoi thy li ch mang li trong vic

cung cp cc dch v bng rng ti cc thu bao. Nhng tin b nhanh chng trong lnhvc thu pht v cp si quang m ra mt tim nng ln trong vic pht trin h tng

FTTH. FTTH c xem nh mt gii php hon ho trong vic thay th mng cp ng

hin ti nhm cung cp cc dch v triple play (bao gm thoi, hnh nh, truy cp d

liu tc cao) v cc ng dng i hi nhiu bng thng.

Hin nay, Vit Nam c mt s nh cung cp dch v FTTH sau :

Thng 8/2006 FPT Telecom chnh thc tr thnh n v u tin cung cp

loi hnh dch v tin tin ny.

Ngy 1/5/2009, VNPT cung cp dch v Internet FTTH trn cp quang vi

tc cao n 20Mbps/20Mbps.

10


11/33

Ngy 15/05/2009, Viettel chnh thc trin khai cung cp dch v truy nhp

Internet FTTH (Fiber To The Home) Cp quang siu tc nhm phc v

khch hng doanh nghip m dch v truy cp Internet hin ti (ADSL v

Leased Line) cha p ng c v tc v chi ph s dng.

Hnh 2.2: Mng FTTx khi trin khai

2.2 So snh mng ADSL v FTTx

2.2.1 Cp quang v cp ng

Trn thc t, khc phc nhc im trong truyn dn thng tin ca cp ng, t

lu ngi ta cho ra i cp quang cng vi nhng tnh nng u vit hn. Khng ging

nh cp ng truyn tn hiu bng in, cp quang dng nh sng truyn tn hiu i.

Chnh v s khc bit m cp quang t b nhiu, tc cao v c kh nng truyn xa

hn. Tuy vy phi n giai on hin nay th cp quang mi c pht trin bng n,

nht l trong lnh vc kt ni lin lc a, kt ni xuyn quc gia. V vic s dng cng

11


12/33

ngh truyn dn hin i ny cng ang bt u thay th dn mng cp ng ADSL phc

v trc tip n ngi s dng.

Cp quang di, mng vi thnh phn ca thy tinh trong sut bng ng knh ca

mt si tc. Chng c sp xp trong b c gi l cp quang v c s dng truyn tn hiu trong khong cch rt xa. Cp quang c cu to gm dy dn trung tm l

si thy tinh hoc plastic c tinh ch nhm cho php truyn i ti a cc tn hiu

nh sng. Si quang c trng mt lp lt nhm phn chiu tt cc tn hiu.

Cp quang gm cc phn sau:

Core : Trung tm phn chiu ca si quang ni nh sng i

Cladding : Vt cht quang bn ngoi bao bc li m phn x nh sng tr livo li.

Buffer coating : Lp ph do bn ngoi bo v si khng b hng v m t

Jacket: Hng trm hay hng ngn si quang c t trong b gi l cp

quang. Nhng b ny c bo v bi lp ph bn ngoi ca cp c gi l

jacket.

Khi pht tn hiu th mt it pht sng (LED) hoc laser s truyn d liu xung nh

sng vo cp quang. Cn khi nhn th s s dng cm ng quang chuyn xung nh sng

ngc thnh d liu. So vi cp ng, cp quang ch truyn sng nh sng (khng truyn

tn hiu in) nn nhanh, khng b nhiu v b nghe trm (tn hiu nh sng t si quang

khng b nhiu vi nhng si khc trong cng cp, iu ny lm cho cht lng tn hiu

tt hn). suy dn thp hn cc loi cp ng (tn hiu b mt trong cp quang t hn

trong cp ng) nn c th ti cc tn hiu i xa hng ngn km. Dung lng ti ca cp

quang cao hn, v si quang mng hn cp ng, nhiu si quang c th c b vo vi

ng knh cho hn cp ng. iu ny cho php nhiu knh i qua mt si cp.

12


13/33

Cp quang cng s dng in ngun t hn, bi v tn hiu trong cp quang gim t,

my pht c th s dng ngun thp hn thay v my pht vi in th cao c dng

trong cp ng.

Cn tn hiu s th cp quang rt l tng thch hp ti thng tin dng s m cbit hu dng trong mng my tnh. Cp quang cng khng chy, v khng c in xuyn

qua cp quang, do khng c nguy c ha hn xy ra. Tuy vy, cp quang v cc thit

b i km li rt t tin so vi cc loi cp ng.

2.2.2 Mt s tiu ch v cht lng dch v gia ADSL v FTTx

Hin nay, cng ngh FTTH (Fiber-To-The-Home l mng vin thng bng thng rng

bng cp quang c ni n tn nh cung cp cc dch v tc cao nh in thoi,

Internet tc cao v TV) ang c trin khai kh mnh m trn th gii. Khi dng

cng ngh FTTH, ng truyn dn hon ton bng cp quang ti tn phng my ca

ngi s dng. Cht lng truyn dn tn hiu bn b n nh khng b suy hao tn hiu

bi nhiu in t, thi tit hay chiu di cp nh i vi ADSL. bo mt rt cao. Vi

ADSL, kh nng bo mt thp hn v c th b nh cp tn hiu trn ng dy, cn vi

FTTH th hu nh khng th b nh cp tn hiu trn ng dy. Vi cng ngh FTTH,

nh cung cp dch v c th cung cp tc download ln n 10 Gigabit/giy, nhanh

gp 200 ln so vi ADSL 2+ (hin ch c th p ng 20 Megabit/giy). Tc truyn

dn vi ADSL l khng cn bng, c tc ti ln lun nh hn tc ti xung (Bt

i xng, Download > Upload) v ti a 20 Mbps. Cn FTTH cho php cn bng, tc

ti ln v ti xung nh nhau (i xng, Download = Upload) v cho php ti a l 10

Gbps, c th phc v cng mt lc cho hng trm my tnh. FTTH c bit hiu qu vi

cc dch v: Hosting Server ring, VPN (mng ring o), Truyn d liu, Game Online,

IPTV (truyn hnh tng tc), VoD (xem phim theo yu cu), Video Conferrence (hi

ngh truyn hnh), IP Cameravi u th bng thng truyn ti d liu cao, c th nng

cp ln bng thng ln ti 1Gbps, An ton d liu, n nh cao, khng b nh hng

bi nhiu in, t trng...

13


14/33

Yu t so snh ADSL FTTx

Mi trng truyn tn hiu Cp ng Cp quang

n nh D b suy hao do tn hiu

in t, thi tit, chiu di

cp

Khng b nh hng

Bo mt bo mt thp, d b

nh cp tn hiu ng

dy

bo mt cao, khng

th nh cp tn hiu

trn ng truyn

Tc truyn dn (Upload v

download )

Bt i xng :

Download > Upload

Tc ti a l 20 Mbps

Cho php cn bng :

Upload = download

Tc cho php l

10Gbps

Chiu di cp Ti a l 2,5 km t

c s n nh

Ti a 10 km

Kh nng p ng cc dch v

bng rng: Hosting server

ring, VPN, hi ngh truyn

hnh

Khng ph hp v tc

thp

Rt ph hp v tc

rt cao v c th ty

bin tc .

Bng 2.3 : So snh ADSL v FTTx da trn mt s tiu ch

14


15/33

CHNG 3: CC DCH V TRIN KHAI TRN FTTH

Hnh 3.1: s trin khai trn FTTH

3.1 Dch v DATA/INTERNET

Edge200 c:

- 2 port 1Gigabit/s

- 2 port 100BT

Edge2000 c 8 port Gigabit (2 port trn card SCM v 6 port trn Network cards)

C th gn trc tip cc lung tc cao t nh cung cp dch v n mi card

trn b trung tm. Hoc c th gn thng qua mt router chia s cho nhiu nh khai

thc hn na

15


16/33

Hnh 3.2: Mt h tng kt ni nhiu nh cung cp dich v DATA/INTERNET

IP Unicast data c kt ni n b trung tm t nh khai thc c phn chia

theo VLAN.

QoS (Quality of Service) c Alloptic h tr bng cch cu hnh bi VLAN ID

hoc Ethernet Type of Service (TOS) v Differential Service Code Points

(Diffserv/DSCP) c thc hin ti pha ngi dng v thc hin bi b trung tm. QoS

c duy tr bi ngi dng theo tng ng dng mong mun theo tng VLAN v mi

VLAN s c b trung tm x l theo yu cu.

Ngoi vic qun l thit b ONU d dng thng qua trnh qun l GigaVU, bohiu trng thi thit b u cui, Alloptic cn cho php ISP qun l bng thng trn tng

port ca ONU, qun l v cung cp cng nh hn ch dch v trn tng port:

Khi ISP c nhu cu s dng 1 ONU cung cp dch v cho nhiu khch hng

nh khc nhau trong cng mt khu vc, vic ny s ch lm vn cu hnh h thng.

16


17/33

Phn mm qun l cho php gn bng thng theo tng cp nx64Kbps n mt port

bt k ca mt ONU bt k. iu ny gip ISP c nhiu ty chn cho cc gi dch v ca

mnh. Tn dng c ti a bng thng d tha khi nh cu dch v ca khch hng

khng cn p ng vi bng thng cao.Khi cn thit th vic thay i tc hoc thay i nh cung cp dch v trn mi

cng c thc hin thng qua phn mm ti b trung tm m khng cn xung n

khch hng.

Khi khch hng khng cn s dng dch v na th thc hin vic ng/m cng

ch cn vi thao tc nh t b trung tm.

Vic qun l dch v trn tng cng cng mang li s tin li cho cc ISP khi nhu

cu v dch v ca khch hng ngy cng kh khn, nhng mong mun i khi kh p

ng c, khi trn cng mt khu vc, nhu cu v dch v ca mi khch hng li khc

nhau.

Giao din GigaVU cho php gn mc bng thng trn tng Port ca ONU.

Hnh 3.3: Giao din cu hnh qun ly bng thng

17


18/33

3.2 Kt ni nhiu nh cung cp dch v thoi VoIP

Alloptic c th hot ng cng lc ng thi cho thoi TDM v thoi VoIP.

Thoi VoIP c gn mt VLAN m thit b Alloptic ch ng vai tr truyn dn

v khng c bt k s can thip no vo gi data.

C nhiu nh cung cp dch v c kt ni n v khch hng c ty la

chn hoc thay i.3.3 Kt ni cho nhiu nh cung cp Video (RF v IPTV):

3.3.1 i vi RF video (truyn hnh cp):

o Tn hiu truyn hnh cp (hoc v tinh) sau khi c ghp knh s c

khuych i trc khi u ni vo b trung tm qua cng video quang.

o Tn hiu video RF s s dng bc sng 1550nm ring bit khi truyn dn

trn PON khng gy nhiu qua hai bc sng ca data 1490nm v 1310nm

o n u cui khch hng s trch tn hiu RF video qua cng coax kt ni n

TV truyn thng (hoc qua b chia/khuych i RF ni n nhiu tng/nhiu TV).

3.3.2 i vi IPTV:

o B trung tm hat ng nh mt proxy c tnh nng Multicast IGMP (Internet

Group Management Protocol). Mi tn hiu video s c gn mt a ch Multicast IP

v TCP port number.

o Trong cng ngh IPTV hin nay khch hng phi s dng Set-Top-Box

yu cu knh. Lc Alloptic s truyn dn tn hiu video theo yu cu v n ONU

tng ng.

o Mi ONU data port c gn mt VLAN cho IPTV v lin kt vi b lc

MAC ID ca STB.

o Alloptic s dng phng thc Multicast do t tn bng thng truyn dn

n nh khai thc. Mi Multicast IPTV t nh khai thc u c pht trn cc knh

ring cho STB chn knh v tnh cc, tt c cc tn hiu ny u c truyn dn

thng qua mng Alloptic.

18


19/33

o QoS c thc hin bi VLAN ID hoc TOS v DSCP

o Bn cnh c 02 chng trnh c bit l xem phim theo yu cu (VoD) v

m nhc theo yu cu (MoD)/Karaoke vi hng trm phim l/b/ti liu v clip nhc hp

dn c sp xp theo danh mc d tra cu s dng m khng cn ra ca hng CD thumn. s dng c dch v truyn hnh tng tc IPTV cn nhng thit b sau:

- ng truyn Internet (ADSL hoc FTTx)

- B gii m (Set-top-box)

- Tivi/LCD (tt nht c h tr Full HD)

Hnh 3.4: kt ni c minh ho

19


20/33

CHNG 4:QU TRNH LP T V BO DNG MNG FTTH

4.1 Qu trnh lp t

4.1.1 Nhng quy nh chung :

1) Thi cng xy dng tuyn thng tin cp quang phi tun theo ng n thit k

c ph chun v nhng tiu chun k thut, quy phm, quy chun xy dng, quy trnh

thi cng.

2) Khi cha c n thit k chnh thc c cp c thm quyn ph duyt, nht thit

khng c khi cng xy dng cng trnh. Ch u t cn t chc bn giao mt bngthi cng v tuyn thi cng gia cc bn: Ch u t, n v thi cng, v cc n v khc

c lien quan.

3) Trc khi thi cng phi c y cc giy php xy dng.

4) n v thi cng phi lp k hoch thi cng ( phng n thi cng, thit k t chc

thi cng) m bo thi cng ng theo thit k v tiu chun, quy trnh, quy phm, m

bo thi cng ng khi lng, thi hn v gi thnh xy dng.

5) n v thi cng khng c t sa i thit k.

6) Cc vt liu s dng trong cng trnh phi tun th theo tng quy nh trong thit

k. Trng hp cn thay i vt liu khc vi n thit k phi c s ng ca cp

c thm quyn.

7) Tt c cc loi vt liu trc khi em dng vo cng trnh phi c nghim thu vcht lng v s lng.

8) Vt liu, thit b, dng c a ra hin trng thi cng phi c kho bo qun v

phn cng ngi qun l theo ng quy trnh quy phm v bo qun vt t.

20


21/33

9) Phi o kim tra cp trc v sau khi thi cng. Kim tra cc hn mc cn thit khc

ca tuyn cp.

10) Lc ko cp khng c ln hn khi lng ca 1 Km cp.

11) Bn knh cong phi nh hn bn knh cong cho php ca cp (ln hn 20 ln

ng knh cp).

12) Phi d cp ti thiu l 12m ti cc im ni mng song v 30m cp nhp

trm cho mi u cp. Cp d phi c qun gn gang vi bn knh ln hn bn knh

cong cho php ca cp.

13) Khi thi cng cn phi c phng n m bo an ton cng trnh, an ton lao ng,ch bo v ti sn ca nhn dn v ca Nh Nc ti nhng ni ng cp i qua.

14) Khi xy dng tuyn mi gn tuyn c ang s dng,hoc sa cha, lp t thm

cp trn tuyn ang s dng phi lin h cht ch vi cc c s Bu in a phng,

chnh quyn a phng v cc c s hu quan.

15) Vic thi cng phi nhanh, gn, m bo an ton giao thong v m bo v sinh

mi trng, sinh thi.

16) Phi nh du tuyn cp, s cp, n v s dng bng cc cc mc, bin bo. C

ba b cp cn c mt bin bo. Ngoi ra cn bo hiu nhng ni cp i hng, qua

ng, qua cu v qua cc cng trnh khc.

4.1.2 Quy trnh lp t cp treo:

4.1.2.1 o h:

a. Trc khi o h phi o li v tr cc mc.

b. H ct phi ng quy cch thit k.

c. o h phi li cc mc d kim tra theo di.

d. Khi o h, t c em ln cn pha ngc vi pha dng ct. t phi

cch xa ming h khong 20 cm. H o trong ngy cn dng ct ngay.

21


22/33

e. H dy co ( h chn chng ) phi c o dch ra ngoi ct mc, theo hng ca

dy co( hng ca chn chng) mt khong ty theo su ca mng dy co ( mng

chn chng )v ty theo t s L/H ca ct. o thm mt mng xin cng dy co cho

tht thng, lp dy co ( lp chn chng ) ng hng chu lc.Trong : L l khong cch chn dy co, chn chng n chn ct. H l cao ct.

f. Khi o h cho ct v dy co pha ng ci thng c ngi qua li, trong

trng hp o xong cha kp dng ct, chon dy co hoc chn chng th phi y vn,

lm bo hiu ch dn ngn nga tai nn.

4.1.2.2 Lp t dy co:

a. Cng dy co cn m bo ng t s L/H trong thit k.b. Cng dy co ct gc v ct u cui phi m bo ng ngn ct. Dy co phi

nm trn ng phn gic ca gc hp thnh bi hai pha ca cp theo chiu ngc vi

lc cng ca cp. Cc mi qun buc phi chc chn, gn v p. Dy co t ngn n

gc thng, khng gy gp.

c. B phn dy co qun vo ct, b phn qun buc bng dy dy st, b phn dy co

t qun, b phn lp thm vo m dy co u phi sn chng r. B phn dy co chn

di t v b phn tri ln khi mt t 30 cm tr xung phi c bin php chng r.d. Khi qun buc dy co nn dng dy st mm qun buc hoc c th dng cch

t qun. Phi m bo k thut mi qun buc.

e. Trng hp trn ct c hai dy co cng hng th ch ni lin gia thn ca hai

dy co v chn dy co phi dng vng m dy co ring bit.

f. Khi chon dy co phi o mt rnh xin t y h ln n ch cc mc dy co

lm cho chn dy co ni vi than dy co nm trn mt ng thng, chiu di tri ln

khi mt t nn ly l 20-30 cm.

4.1.2.3 Lp t cp:

a. Vic m bo an ton trong khi lp t phi c tnh n trc khi lp t cp.

b. Phi tun th y cng tc chun b lp t cp quang treo:

22


23/33

-Dn quang mt bng thi cng.

- Lp rng rc trn ct.

- Lp t ti ko c trang b cu ch ngt.

- Treo dy ko.

- Lm u ko.

b. Ko cp: Tc ko phi nh hn 20m/phut.

c. Cng cp:

-Kim tra x l xon cp.

-Dng ti iu chnh cng ca dy treo.

- iu chnh vng ca cp theo thit k.

-Khi kp dy treo dng dng c iu chnh tng dy tr gip kp dy treo.

d. Mng sng cp, cp d tr c treo trc tip vo ct.

e. Phi lp bin bo hiu ti nhng ch cn thit, ngoi ra c bit ch ni qua

ng, qua cu, qua cc cng trnh khc v.v

f. Trong trng hp lp t cp qua song, m ly, a hnh phc tpcp quang

c treo trn dy gia cng chu lc. iu ny i hi phi c h thng rng rc c

t trn mi u ct v dc theo ng dy gia cng treo cp. Ti ko cp c xu qua

h thng ny v ni vi cp. Dng ti c cu ch ko cp ko cp t cun cp qua

khong cch gia cc ct.

4.1.2.4Cc trng hp treo cp c bit:

a, Cp quang treo chung vi ng dy in lc. V khong ct ca in lc di hn

khong ct ca bu in, khi thi cng cp quang trong trng hp phi p dng theokhong ct di v ct vt. Khi thi cng cp quang cng ng dy din lc phi ch

tnh ton di cun cp ph hp vi khong ct, trnh trng hp phi ni cp

khong gia hai ct, chn cp thi cng theo thit k. Trc khi thi cng phi lin h cht

23


24/33

ch vi c quan qun l ng dy in lc, phi ct in v c bo hiu thi cng tuyn

cp quang, ng k thi gian lm vic hng ngy v khong thi gian thi cng.

b, i vi cp quang lp p qua cu, cp phi c t trn mng cp hoc trong ng st

bo v. Phi tnh ton sao cho khng c mi ni trn cu. Sau khi lp t xong phi vitk hiu nh du CAP QUANG.

4.1.3 Quy trnh lp t cp chn trc tip:1, Vic o rnh cn c thc hin theo quy nh v rnh chn cp v ph hp vi thit

k.

2, Trc khi t cp phi lt y rnh mt lp cp hoc t vn dy 10 cm.

3, Cn phi lm sch rnh cp trc khi lp t, c bit ch khng rc ri, g v

cc thnh phn l thc n ca mi.

4, Trc khi lp rnh cp ri tip ln trn mt lp ct hoc t vn dy 10 cm.

5, Bng bo hiu phi c t v tr ngay pha trn ca cp, pha trn cp 30 cm trong

cc trng hp bnh thng. Trn bng bo hiu phi in ch CP QUANG bn di

6, Phi t mc bo hiu ti nhng im theo thit k trn tuyn cp, ngoi ra ch t

thm bin bo hiu ti ni c nhiu phng tin i li, qua sng, qua , qua ng.v.v

3.1.4Quy trnh lp t cp trong cng cp:1, Chng b dng c ko cp:

a, Dy ti ko cp:dy ti dung ko cp hoc ng cp ph t trong ng ng

chon sn phi l dy ti ko cp thch hp trnh lm t v ng cp. Ngoi ra dy ti

phi m bo cc yu cu sau:

-Mi mt mt phi c nh du xc nh chiu di.

-Phi c bn ln hn lc cng c tnh ln nht.

-Cc im ni dy ti ko cp v cp phi c khu li tng kh nng lin kt.

-Phi c khi xoay gia dy ti ko cp v cp.

24


25/33

b, Rng rc: Rng rc s dng gim ma st phi c ng knh ln hn bn knh cong

cho php ca cp.

c, Ti ko cp: Ti ko cp chnh phi c trang b cu ch ko cp. Ti ko cp ph

c t ti b cp tr gip ko cho ti ko cp chnh. Ti ko cp ph phi c kchthc ph hp vi b cp. R ko cp c ang bng kim loi to thnh r li. R ko

cp c gn vi mt khp xoay.

d, Cc dng c cn thit khc nh: Kch cp, bao ti, phu .v.v

2, Lp t h thng cng cp: Kt cu cng cp khi thi cng phi c rng v su

ng vi thit k, t o ln trn gn ming rnh phi m bo khng x xung

rnh, khi o xong phi t ngay ng trnh b l t. Khong cch gia cc ng,

khong cch lp ng gn y rnh nht phi tun theo thit k.a. Khi vn chuyn phi ch :

-Sn xe khng ngn hn chiu di ng.

-Khng dng xe ben t ng.

-Khi bc xp phi c hai ngi, mi ngi mt u ng.

b. Khi lu kho phi ch :

-xp ng theo chiu cao khng qu 1,75m.

- G ng phi thng.

3) Lp rp ng nha:

a. Phi chng b y cc dng c lp ng bao gm:

-Ca tay hoc ko ct ng.

-Gia.

-Bt khc kim loi.

25


26/33

-Xng cng nghip.

-Nha dn.

-Gi lau kh.

b.Ct ng bng ca tay hoc ko ct ng.

c. Gt sch ba via, gia st mp ngoi.

d. Lm sch bi du m bng gi kh sch ( vi xng cng nghip ).

e.nh du phn ng s lp vo ph tng.

4). Xy dng b cp, h ni:

Trc khi thi cng b cp,h ni ti ni c ngi qua li phi cng dy v lp cc

bin bo.

Thi cng xy dng b cp, h ni trn cc a hnh khc nhau phi theo thit k v

quy hoch sau:

a. o h theo su xc nh ty thuc vo su ca b cp, h ni cn xy

dng.t o ln phi vn chuyn i ngay, nu kt cu t cn ng cc th

phi ng cc vi su so vi y b l 1,2m. Phi mt lp mng gch v, ct trc

khi b tong.

b. Cc tm b tong phi c c ng kch c va kht vi cc chi tit lp t.

c. B cp, h ni phi c xy dng ng quy cch, kch thc theo quy nh v

cng b do ngnh quy nh. H ni cp phi rng cha cp h, phi c ch g,

t bo v mng sng cp.

5) Lp t cp:

a. Cht bi trn phi c cc im u ca ng, tt c cc v tr a cp vo,

nhng v tr ko cp trung gian.

26


27/33

b. Cc t tnh ca cht bi trn cp quang phi m bo l:

-Thch ng vi nhit ngoi tri.

-Chng chy.

-H s ma st thp ( < 0,25).

-Cht lng khng i trong qu trnh lp t.

-Khng nh hng n v cp.

-c kim tra trc khi s dng.

6) Trc khi lp t, tt c cc b cp phi c kim tra m bo rng chng honton an ton v sch s.

7) Chng b cp, dy ti ko cp, r ko cp,cu ch ko cp, ti ( my ko cp ).

8) Xc nh cc ng cp c s dng cho lp t.

9) Phi m bo cc ng cp u sch s. Nu cn thit phi lm sch ng cp.

10) Nu trong ng cp c sn cp c, khi cn xc nh chng loi cp v ch shu ca tuyn cp ny, phi bo cho ch s hu bit v hot ng lp t cp ang din

ra v phi xc nh cc yu cu an ton cn thit.

11) Phi gim st khng cp b un cong qu mc khi ko cp qua nhng khc

cong.

12) Phi t tt c cc thit b cn thit v tr thch hp.

13) Nu cp c t vo trong ng cp ph th phi lp t ng cp ph trc, c th

l:

a.nh v ti cho ng cp ph.

27


28/33

b.Gn mt r ko cp c khp xoay vo bn trong v gn dy ti ko cp vo r ko

cp.

c.Phi m bo tt c cc ti v rng rc s dng tt.

d.Trong qu trnh thao tc phi ch khng cho qun o, tay chn hay mt vt no

khc vng vo b phn chuyn ng ca ti ( my ko ).Tt c mi ngi trong nhm

thc hin cng vic phi c lin lc lin tc vi nhau bng cc thit b thng tin.

e. t ng ph bn trong ng cp chnh trc khi ko cp.

f. Khi ko ng cp ph phi s dng cp bi trn trong trng hp cn thit. S dng

cc on ng c di ph hp trong trng hp cn thit v sau ni nhng on nyvi nhau bng cc b ni ng cp. Cc dy ti ko cp cng c th c ni tng t.

g. nhng ni khng c kh nng khm bng tay th ta c th dng ti ko cc ng

cp ph, nhng phi m bo an ton.

h)Ton b chiu di ca ng cp ph v dy ti ko cp c ni vi nhau to ra

mt chiu di lin tc phc v cho vic ko cp.

k) Phi cho ng cp ph di ra mt on m bo s co dn ca ng.

14) Phi gn r ko cp v khp xoay mt cch thch hp vo vi cp. Phi m bo

r ko cp v khp xoay c th lp t d dng vo tt c cc loi ng chnh v ph.

15) Khng s dng vi dt thay cho r ko cp.

16) Ni dy ti ko cp vo khp xoay phi m bo chc chn.

17) Hiu chnh rng rc v trc ti cho ph hp.

18) Cho cht bi trn vo u ng dn cp v vo tt c cc v tr yu cu phi c cht

bi trn.

28


29/33

19) Nu qu kh khn khi ko cp bng tay c th chuyn sang ko cp bng ti

nhng vi tc chm. Phi trnh git cc khi ko cp. Phi lun lun gi lc cng ca

cp di lc cng ti a cho php. Khi ti cp ra khi ti phi m bo cp khng b

xon.

20) Quay trc ti bng tay duy try chng gia cun ti v ng dn cp.

21) Phi trnh ko git cc, dng t ngt.

22) Trong qu trnh ko cp nu cu ch c phi kim tra tt nghn trn tuyn cp v

c bin php x l kp thi, c th l:

a. Kim tra cc on cong m bo l khng b tt nghn, gp khc qu ln, ccrng rc hot ng trn u.

b .Phi m bo ti cp trn.

c. Phi a cht bi trn vo trc mi ch un.

d. Lm ngn tuyn cp cn ko. Chuyn v tr ko ti v tr im gia ca tuyn v bt

u ko li. Ko cp ra khi b cp. S dng cch cun cp hnh s tm nm ngang

gim xon ca cp.

e. Chn v tr bt u ko cp thch hp v ko cp qua phn cn li ca tuyn cp.

f. C th s dng mt ti ko th hai v tr trung gian h tr cho vic ko cp.

g. Cn phi ko cp c th cun khong t mt n ba vng xung quanh ti.

h. Lp thm cc rng rc b cp trung gian nu cn thit.

i. Phi m bo lin lc gia cc nhm ko ti.

j. Phi m bo cp d trn trc ti khi ko cp vo trong b cp t nht l 3m.

k. Cun ti trung gian cn phi ko cp ng thi vi cun ti chnh trong khi vn

duy tr c vng cn thit.

29


30/33

l. Khi cp chuyn hng th thc hin xp ct cp hnh s tm nm ngang.

23) Phn cp qua b phi lun ng nha PVC hoc ng cao su bo v cp. Cp qua

b khng c mi ni th khng cn d.

24) Sau khi lp t cp xong phi dng my o kim tra si m bo rng cp

khng b h hi trong qu trnh ko.

4.1.5 Quy trnh lp t cp trong hm cp:

1) Trong hm cp c sn cp c th phi xc nh chng loi v ch s hu ca

tuyn cp ny, phi bo cho ch s hu bit v hot ng lp t cp ang din ra v phi

xc nh yu cu an ton cn thit. Ti nhng hm ln khi thi cng lp t cp phi c

bin php cnh gii v ng k gi lm vic m bo an ton cn thit.

2) Phi t tt c cc thit b phc v lp t v tr ph hp.

3) Gim st cht ch vic ko cp ti cc on cong, phi m bo l cp khng b

nghn, khng b un cong qu bn knh cong nh nht cho php ca cp, cp khng b

xon, cc rng rc hot ng trn u. Nu b tt nghn th thc hin: Lm ngn tuyn

cp cn ko, chuyn v tr ko ti im gia ca tuyn v bt u ko li.

4.1.6 Quy trnh lp t cp trong nh:

4.1.6.1 yu cu k thut:

a. Cp quang lp t trong nh phi c t trong ng, cc h thng cu cp.v.v

b. Trc khi lp t, tt c cc im un phi m bo nhn trn.

c. Nu cp khc t chng ln cp quang th phi dng thm ng bo v cp.

d. Khi lp cp dng thng ng phi m bo trng lng ca cp khng c vt

qu ti cng ln nht ca cp khi lp t.

30


31/33

e. Cp i thng ng c kp ph tr ti cc im trung gian gim ti ko cng

ca cp. Lc cng ca cp phi m bo nh hn trng lng 1 km cp.

f. Khng c cp bin dng, bp trong bt c on no. Kp gi cp phi thng,

nhn trnh nh hng n cp. Dy nhy cp cn c lun trong ng nha mm ti

nhng v tr cn thit.

g. Nu khng dng kp cp th c th s dng b treo cp ti cui cp v on trung

gian dc theo phng i ln treo cp. B treo cp phi khng c lm bin dng cp.

Ti ch treo cp c th tht cht cp trnh trng hp cp b trt ra ngoi. Trng

hp c b treo cp c gn ln x, tng th phi m bo chc chn rng ung cong

ca cp khng vt qu quy nh.

h. Tuyn cp nm ngang c treo ln trn nh, ng dn cp, cu cp.v.v u phi

c dn nhn CAP QUANG.

4.1.6.2 Lp t cp:

a. Cp i trong nh lun c lp bng tay. Khi cp quang i cng vi loi cp khc

hoc kh ko th cn phi c bi trn.

b. Kim tra tt c cc hp x l cp, cc ng cha cp, cc cu cp .v.vm bo v

tha mn yu cu k thut i vi cp v khng c yu cu tr ngi trong qu trnh thi

cng.

c. Phi m bo bn knh cong ca cp ln hn bn knh cong cho php ti tt c cc

im.

d. Phi cun cp trn sn trnh xon cp.

e. Phi c d tr cp ti hp x l cp.

31


32/33

4.2 Hot ng qun l bo dng trong h thng FTTH

tha mn nhu cu ca khch hng v p ng dch v cht lng cao, mng

FTTH phi trin khai th tc hot ng qun l v bo dng ng tin cy. Th tc ny

h tr vic tnh cc, bo mt, bo dng, cung cp v gim st hiu sut mng. N cth thc hin vic s dng cc chun hay dng c phn mm h thng h tr hot ng

m rng trong h thng qun l mng. C nhiu chng trnh h tr hot ng c th cp

quyn thng qua trnh duyt web v vic chn la cc ng dng rng ri, n cho php

qun l mng cu hnh v iu khin hng trm phn t trong . Vic cung cp phn

phi cc mc dch v cung cp v cu hnh khc nhau cho cc loi dch v thoi, d liu

v video cho khch hng. Nh iu hnh mng cng nh c ch t ng cn xc nh nu

thit b ti u cui khch hng c th cung cp cc dch v c yu cu. V d nh viccung cp phi xc nh nu ONU c kh nng iu khin tc d liu ca mnh d c

kh nng kt hp vi kim tra hay khng th n cng h tr hot ng t xa. iu ny th

quan trng i vi nh cung cp dch v, vic qun l v xc nh cc vn t xa c th

ngn nga vic yu cu cc dch v chi ph t . Chc nng bo dng hay qun l li

trnh cc li tim n v s gim st trong mng FTTH. Nu li xy ra, tin trnh bo

dng cn xc nh v lm r cng nhanh cng tt tha mn nhu cu khch hng. Kh

nng kt hp vi kim tra thay i thng tin trng thi gia ONU v OLT bao gm

chc nng loop-back iu khin t xa pht hin li trn mch hay cp, thng k li

ONU v thot khi ngun trong trng hp c s c ti ONU. Hnh 3.34 m t tn hiu

iu khin trng thi mch vng, n c khi to OLT v truyn n ONU sau

ONU bo co trng thi v truyn ngc v OLT. Vic bo co ny ch th mi th

hot ng tt hay chng c th c dng xc nh nguyn nhn tc li bit cao.

32


33/33

Ngun: Gerd Keiser, FTTX Concepts and Applications,2006

Hnh 4.1 : OLT khi to loop-back iu khin t xa

tim hieu trien khai lap dat mang truy nhap quang ftth

Documents