FTTH - kev piav qhia

Qhov txawv ntawm fiber ntau qhov sib txawv yog qhov sib txawv hauv qhov kev ncua deb ntawm qhov ze thiab ze tshaj plaws ONU / ONT los ntawm OLT.

Hauv GPON, qhov ntau tshaj ntawm cov hluav taws xob fiber ntau yog 20 kms. Qhov no cuam tshuam qhov loj me ntawm lub qhov rais ranging thiab muab kev ua raws li [ITU-T G.983.1].

Logical ncav cuag txhais tau tias qhov kev ncua deb tshaj plaws uas tuaj yeem ua tiav rau ib qhov kev xa mus rau ib qho, tsis hais txog ntawm qhov nyiaj siv kho qhov muag. Logical ncav cuag yog qhov chaw siab tshaj plaws ntawm ONU / ONT thiab OLT tshwj tsis yog rau txoj kev txwv ntawm txheej lub cev.

Hauv GPON, qhov siab tshaj plaws qhov siab mus txog yog txhais tau tias 60 kms.

Lub ntsiab lus txhais hloov mus qeeb yog qhov nruab nrab ntawm cov ntws thiab nce toj qeeb qhov tseem ceeb ntawm cov ntsiab lus siv. Tus nqi no yog txiav txim siab los ntawm kev ntsuas ncig mus ncig qeeb thiab tom qab ntawd muab faib los ntawm 2.

GPON yuav tsum haum rau cov kev pabcuam uas xav tau lub siab tshaj plaws lub suab sib pauv hloov qeeb ntawm 1.5 ms. Lub kaw lus GPON yuav tsum muaj qhov siab tshaj plaws txhais tau tias Tshais Hloov Chaw Xa Sijhawm ntawm tsawg dua1.5 ms nruab nrab ntawm TV siv cov ntsiab lus.

OAN yog qhov kev nkag mus rau kev nkag mus sib faib siv tib lub network sab sib cuam tshuam thiab txhawb nqa los ntawm cov kho qhov muag nkag mus rau cov kab ke. OAN yuav suav nrog ntau tus lej ntawm ODN uas txuas nrog tib OLT.

Hauv PON cov ntsiab lus teb, ib tsob ntoo ntawm cov kab hluav taws xob hauv cov kab sib txuas, txuas ntxiv nrog lub zog lossis nthwv dej sib cais, lim lossis lwm yam khoom siv kho qhov muag.

Cov cuab yeej uas kaw tseg qhov xaus (ua hauv paus) qhov kawg ntawm ODN. Tom qab ntawd coj los siv PON raws tu qauv xws li uas tau txhais los ntawm [ITU-T G.984]; thiab tom qab ntawd yoog PONPDUs rau kev sib txuas lus uplink dhau ntawm cov chaw muab kev pabcuam.

OLT muab kev tswj hwm thiab tswj cov haujlwm rau cov subtended ODN thiab ONUs.

Ib tus neeg siv khoom nkaus xwb uas tshem tawm ib qho ntawm cov khoom faib (nplooj) kawg ntawm ODN, siv PON raws tu qauv, thiab yoog PON PDUs rau kev pabcuam cuam tshuam. ONT yog rooj plaub tshwj xeeb ntawm ONU.

Lub sij hawm ib txwm hais txog ib qho khoom siv twg ua kom tshem ib qho twg ntawm qhov faib (nplooj) kawg ntawm ODN, siv PON raws tu qauv, thiab yoog PON PDU.

Kev ncav cuag lub cev yog txhais tau tias qhov siab tshaj plaws ntawm lub cev uas tuaj yeem ua tiav rau qhov kev xa tawm tshwj xeeb. Txij li, 'Kev ncav cuag Lub Cev' yog qhov siab tshaj plaws ntawm lub cev nruab nrab ntawm ONU / ONT thiab OLT. Txawm li cas los xij, hauv GPON, ob txoj kev xaiv tau txhais rau lub cev ncav cuag: 10 kms, thiab 20 kms. Nws tau kwv yees tias 10 km yog qhov chaw siab tshaj plaws uas FP-LD tuaj yeem siv nyob rau hauv ONU rau cov lej siab xws li 1.25 Gbit / s lossis siab tshaj.

Cov kev pabcuam hauv FTTH yog txhais tias yog kev pabcuam network uas yuav tsum tau ua los ntawm cov tswj hwm. Kev pabcuam tau piav qhia los ntawm ib lub npe uas pom zoo los ntawm txhua tus, tsis hais nws yog lub npe thav duab lossis lub npe dav dav.

GPON hom phiaj ntawm cov khoom xa hluav taws xob ntau dua los sis sib npaug ntawm 1.2 Gbit / s. Raws li, GPON txheeb xyuas ob kab kev sib txuas ceev raws li hauv qab no -

• 1.2 Gbps nce, 2.4 Gbps qis dua

• 2.4 Gbps nce, 2.4 Gbps qis dua

Tus nqi sib tw tseem ceeb tshaj plaws yog 1.2 Gbps nce, 2.4 Gbps qis, kwv yees yuav luag tag nrho cov kev siv thiab kev npaj xa tawm ntawm GPON systems.

Qhov loj dua qhov sib faib feem ntau yog rau GPON, qhov ntau yig nws yog los ntawm tus nqi kev xav. Txawm li cas los xij, qhov sib cais sib faib loj dua txhais tau tias ntau dua qhov muag pom tau lub zog thiab cov bandwidth sib cais, uas tsim qhov xav tau kom muaj peev nyiaj ntau ntxiv los txhawb nqa lub cev kom ncav cuag. Txheeb cov cim txog li 1:64 yog qhov tseeb rau txheej txheej ntawm lub cev, muab cov thev naus laus zis tam sim no. Txawm li cas los xij, kev cia siab tias qhov kev hloov zuj zus txuas ntxiv ntawm cov kho qhov muag hloov kho, TC txheej yuav tsum xav txog qhov sib cais sib faib txog li 1: 128.

Kev pab cuam ntawm optical fiber -

• Cov nyob deb heev

• Muaj zog, hloov tau thiab ntseeg tau

• Tso cai rau txoj kab uas hla me me thiab lub teeb yuag

• Zoo thiab nyab xeeb

• Kev txhaj tshuaj rau electromagnetic cuam tshuam (EMI)

• Cov nqi qis dua

Ntau cov modules / ntu hauv PON thev naus laus zis yog -

• WDM Coupler

• 1 × N Splitter

• Optical fiber thiab cable

• Khoom Txuas

• ODF / Txee / Subrack

Cov nquag sib xyaw / cov feem hauv PON thev naus laus zis yog -

Hauv OLT -

• Laser transmitter (1490-nm) thiab

• Cov txais laser (1310-nm)

Rau daim ntawv thov CATV -

• Laser amplifier (1550-nm) thiab

• EDFA rau kev ua kom nrov dua lub teeb liab video

Nyob rau ONU -

• Fais fab / roj teeb rau ONU

• Laser transmitter (1310-nm)

• Laser txais (1490-nm)

• Cov neeg txais kev pabcuam rau CATV teeb liab (1550-nm)

Daim ntawv qhia tag nrho ntawm GPON yog - Gigabit Passive Optical Network

GPON yog Txheej Txheem Kho Kom Zoo rau Kev Nkag Tes, raws li ITU-T cov lus qhia tshwj xeeb G.984 series. Nws tuaj yeem muab qhov 20 km ncav cuag nrog 28dB kho qhov muag siv nyiaj los ntawm kev siv chav kawm B + optics nrog 1:32 qhov sib cais.

Cov kev paub uas nquag muaj ntawm GPON muaj raws li qhia hauv qab no.

Kis kab hauv qab -

• 2.4Gbps

• BW rau ib qho ONT yog qhov txaus los muab ntau yam teeb meem ntawm HDTV

• QOS tso cai rau ncua kev nkag tsis yooj yim (lub suab)

Kis tau tus mob kis -

• 1 24Gbps

• Tsawg kawg BW tuaj yeem lav

• Lub sijhawm tsis siv tuaj yeem raug xaiv rau cov neeg siv khoom hnyav

• QOS tso cai rau ncua kev nkag tsis yooj yim (lub suab)

GPON cov qauv tsim nyob rau yav dhau los BPON cov kev qhia tshwj xeeb. Cov lus qhia tshwj xeeb no txhua yam hauv qab -

• G.984.1 - Daim ntawv no piav qhia Gigabit-Capable Passive Optical Network cov yam ntxwv dav dav.

• G.984.2 - Cov ntaub ntawv no piav qhia Gigabit-Capable Passive Optical Network Lub Cev Tshaj Tawm-raws txheej txheej tshwj xeeb.

• G.984.3 - Cov ntaub ntawv no piav qhia Gigabit-Capable Passive Optical Network Transmission convergence txheej specification.

• G.984.3 - Cov ntaub ntawv no piav qhia Gigabit-Capable Passive Optical Network Transmission convergence txheej specification.

GPON cov tshuab muaj qhov tseem ceeb ntawm cov khoom siv hauv lub cev uas tau teeb tsa zoo ib yam li lwm cov PON tes hauj lwm. Yog lawm, cov khoom lag luam tsim rau GPON cov tshuab tshwj xeeb yog tsim los rau GPON thiab tsis hloov pauv nrog EPON lossis BPON iav.

GPON cov haujlwm kuj tseem muaj ntau yam peev xwm ib yam li lwm qhov PON systems muaj. Lub ntsiab sib txawv hauv cov architecture yog GPON hauv cov ntaub ntawv throughput. Gigabit GPON cov txheej txheem encapsulation pub nqa ntau yam kev pabcuam suav nrog ATM, TDM lub suab, thiab Ethernet.

Ib qho ntawm qhov yuav tsum tau ua ntawm lub kaw lus kho qhov muag yog muab cov khoom siv nrog qhov muaj peev xwm txaus kom txuas tau lub teeb liab kho qhov muag mus rau qhov xav tau ntau yam. Muaj peb pawg lossis chav kawm ntawm cov khoom sib txawv yog raws li lub hwj chim thiab rhiab.

Cov chav ntawm Cheebtsam yog -

• Hoob A optics: 5 txog 20dB

• Hoob B optics: 10 txog 25dB

• Chav C optics: 15 txog 30dB

Daim ntawv qhia tag nrho ntawm EPON yog - Ethernet Passive Optical Network.

Ethernet Passive Optical Network (EPON) yog PON encapsulate cov ntaub ntawv nrog Ethernet thiab tuaj yeem muab 1 Gbps txog 10 Gbps muaj peev xwm. EPON ua raws li qhov qub architecture ntawm PON. Ntawm no, DTE txuas rau lub cev ntoo thiab hu ua Optical Line Terminal (OLT).

Nws feem ntau nyob hauv tus muab kev pabcuam, thiab txuas nrog DTE cov ceg ntawm tsob ntoo yog hu ua Optical Network Unit (ONU), nyob hauv thaj chaw ntawm cov neeg yuav khoom. Cov paib los ntawm OLT dhau los ntawm passive splitter mus cuag ONU thiab rov ua lwm yam.

Ntau daim PON thov yuav tsum tau QoS siab (piv txwv IPTV).

EPON tawm QoS mus rau ntau cov khaubncaws sab nraud povtseg -

• VLAN tag

• P cov khoom lossis DiffServ DSCP

Ib qho ntxiv, muaj qhov sib txawv tseem ceeb ntawm LLID thiab Port-ID -

• Ib txwm muaj 1 LLID ib ONU

• Muaj 1 Chaw nres nkoj-ID rau ib qho chaw nres nkoj - yuav muaj ntau yam ntawm ONU

• Qhov no ua rau chaw nres nkoj QoS yooj yim los siv ntawm PON txheej

Cov lus hauv qab no qhia txog qhov sib txawv ntawm GPON thiab EPON.

Ib qho kev daws teeb meem tau siv hauv OLT, siv Kev Qhia thiab Lub Rooj vag cov lus los tsim cov kev pabcuam kis thiab kis ntawm ONUs yog paub tias yog lub tshuab nqus tau cov tshuab bandwidth (DBA).

Kev ua haujlwm EPON yog ua raws Ethernet MAC thiab EPON ntas (raws GbE ntas), tab sis txuas ntxiv yog xav tau -

• MultiPoint Control raws tu qauv PDUs - Nov yog kev tswj hwm raws tu qauv uas siv cov kev tseev kom muaj.

• Qhov taw qhia-rau-taw qhia emulation (kev sib haum xeeb) - Qhov no ua rau EPON zoo li sib txuas-taw-rau-taw qhia thiab EPON MACs muaj qee qhov tshwj xeeb.

• Hloov chaw ntawm CSMA / CD, lawv kis thaum tso cai.

• Lub sijhawm dhau ntawm MAC pawg yuav tsum tsis tu ncua (± 16 ntsis durations).

• Lub sijhawm sijhawm hauv zos yuav tsum tau tswj hwm.

Txheem Ethernet pib nrog qhov tseem ceeb cov ntsiab lus tsis pub 8B preamble -

• 7B ntawm kev hloov pauv thiab xoom 10101010

• 1B ntawm SFD 10101011

Txhawm rau zais PON header tshiab, EPON sau qee qhov ntawm kev thaiv.

DS tsheb tshaj tawm rau txhua tus ONUs, yog li qhov kev hloov siab tseem ceeb yooj yim rau tus neeg siv tsis zoo rau reprogram ONU thiab ntes cov thav ntawv uas xav tau. Cov tsheb khiav hauv Asmeskas tsis pom los ntawm lwm cov ONUs, yog li tsis xav tau lub encryption. Tsis txhob xav txog fiber ntau-tappers vim EPON tsis muab cov qauv encryption, tab sis -

• Tuaj yeem ntxiv nrog IPsec lossis MACsec.

• Coob tus neeg muag khoom tau ntxiv cov tswv ntawm AES-based mechanisms.

BPON siv cov txheej txheem hu ua churning - Churning yog qhov txiaj ntsig kev kho vajtse qis (24b yuam sij) nrog ntau qhov kev ruaj ntseg -

• Cav yog linear - qhov yooj yim paub-ntawv nres

• 24b tus yuam sij tig tau tawm los ua neeg txuas nyob rau hauv 512 sim

Yog li ntawd, G.983.3 ntxiv kev txhawb nqa AES - tam sim no siv hauv GPON.

XPON yog PON tiam tom ntej, uas tuaj yeem txhawb cov ntaub ntawv tus nqi nce mus txog 10G. XPON tuaj yeem faib ua ob pawg, piv txwv li, XG-PON1 thiab XG-PON2. XG-PON1 rov qab sib haum nrog GPON, hos XG-PON2 yog kev tsim kho tshiab kiag li.

Tag nrho daim ntawv ntawm WDM-PON yog - Wavelength Division Multiplex PON.

Hauv WDM-PON, txawv yoj yauv txawv yog txawv rau ONT; txhua ONT tau txais ib qho kev yoo tshwj xeeb thiab nyiam cov kev siv bandwidth ntawm wavelength. Hauv lwm lo lus, WDM-PON ua haujlwm rau lub ntsiab lus Lub Ntsiab Kom Txog Qhov Loj (P2MP) topology.

Daim ntawv qhia tag nrho ntawm ODSM-PON yog - Muaj kev vam meej Spectrum thiab Dynamic PON. Hauv ODSM-PON, lub network tseem tsis tau hloov ntawm CO rau cov neeg siv thaj chaw tshwj tsis yog ib qho hloov pauv, uas yog nquag WDM splitter. A WDM splitter yuav nyob nruab nrab ntawm OLT thiab ONT hloov passive splitter. Hauv ODSM-PON, qhov dej ntws qis txais WDM, txhais tau tias cov ntaub ntawv ntawm ONT siv cov txheej txheem sib txawv rau ONT sib txawv thiab nyob rau sab saud thiab ODSN-PON lees paub siv tshuab dynamic TDMA + WDMA.

Cov lus hauv qab no piav qhia txog XGPON cov qauv -

Cov lus hauv qab no qhia txog XG-PON optical zog chav kawm.

Cov lus hauv qab no qhia txog Attenuation range rau Chav A, B, thiab C raws li ITU.

Cov lus hauv qab no piav qhia txog OLT qhov kis tau tus mob rau Chav Kawm A, B, thiab C raws li ITU.

Cov lus hauv qab no piav qhia txog ONU tus txais ntau rau Chav Kawm A, B, thiab C raws li ITU.

Cov lus hauv qab no piav qhia txog ONU transmitter ntau rau Chav Kawm A, B, thiab C as per ITU.

Cov ntaub ntawv hauv qab no qhia txog OLT tus txais ntau rau Chav Kawm A, B, thiab C raws li ITU.

Tib lub fiber ntau pib los ntawm OLT tau sib cais dhau los ntawm passive optical splitters kom ua haujlwm rau 64 tus neeg siv khoom PMTs. Tib lub fiber ntau nqa ob qho tib si nqis (OLT ntawm ONT) thiab ntws los (ONT ntawm OLT) me ntsis ntws viz., 2.488 Mbps / 1490 nm (1480 - 1500nm qhov rais) thiab 1.244 Mbps / 1310 nm (1260-1360nm qhov rai) los ntawm WDM (Wavelength Division Multiplexing) rau duplex (bi-directional) kev ua haujlwm.

Tib cov roj carbon fiber ntau xa los ntawm OLT rau ONTs yog tshaj tawm nrog ONT lees txais tsuas yog cov tsheb mus rau nws. Kev sib kis tau hluav taws xob yog Lub Sijhawm Kev faib tawm sib txuam (TDMA) nrog txhua ONT sib kis sib kis.

Cov cim qhia hauv TV (muab los ntawm lub satellite Lub Taub Hau Kawg) yog cov kev xaiv tshaj tawm ntawm lub koob thib peb lub koob yees duab ntev ntawm 1550 nm ntawm tib (lossis ntxiv) cov fiber ntau qhia rau hauv FTTx system los ntawm kev siv RF Overlay sub-system. CATV Cov Lus Qhia tuaj yeem tau txuas nrog GPON teeb liab tom qab ua kom nrov nrov los ntawm EDFA.

Cov xov tooj cua RF CATV ua rau hloov kho mus rau 1550 nm wavelength. Nws yog rho tawm los ntawm Demux ua haujlwm sab hauv ONT thiab xa rov qab dav hlau cov kev pabcuam sib txuas rau STB / TV.

Qhov siab tshaj plaws tau tso cai kho qhov muag fais fab teeb tsa ntawm OLT optical port mus rau ONT cov tswv yim yog 28 dB siv thiaj li hu ua Class B kho qhov muag network cov ntsiab lus. ODN Chav A, B, thiab C tau sib txawv tsuas yog siv 'kev xa cov khoom hluav taws xob tso tawm hluav taws xob' thiab 'ntsis-tus nqi kho qhov muag txais tau rhiab. Chav Kawm A muab qhov tsawg tshaj plaws-kho qhov muag nyiaj thiab Chav C muab qhov siab tshaj plaws, thaum raug nqi ob leeg yog nyob rau tib qho kev txiav txim. Rau qhov siab tshaj 1:64 cais piv, Chav B optics feem ntau xa tawm ntawm kev ua lag luam.

Cov ntsiab lus hauv qab no piav qhia NGPON1 -

• G.987 / G.988 XGPON tus qauv tau muab tso rau xyoo 2011.

• Nws txheem txheej XGPON nrog 2.5Gbps ntws los / 10Gbps ntws los.

• GPON thiab XGPON siv cov txheej txheem sib txawv rau kev sib koom ua ke hauv ib qho network.

Cov ntsiab lus hauv qab no piav qhia NGPON2 -

• Tsis suav tias yog sib raug zoo nrog ODN network uas twb muaj lawm, qhib kev cai ntawm PON thev naus laus zis ntau dua.

• Cov ntsiab lus rau WDM PON thiab 40G PON.