{"id":5963,"date":"2018-11-09T02:07:07","date_gmt":"2018-11-08T19:07:07","guid":{"rendered":"https:\/\/vinacap.vn\/?post_type=tin-tuc&p=5963"},"modified":"2023-06-22T16:11:51","modified_gmt":"2023-06-22T09:11:51","slug":"nguyen-tac-hoat-dong-co-ban-cua-cap-quang-va-dau-noi","status":"publish","type":"tin-tuc","link":"https:\/\/vinacap.vn\/zh\/archives\/tin-tuc\/nguyen-tac-hoat-dong-co-ban-cua-cap-quang-va-dau-noi","title":{"rendered":"NGUY\u00caN T\u1eaeC HO\u1ea0T \u0110\u1ed8NG C\u01a0 B\u1ea2N C\u1ee6A C\u00c1P QUANG V\u00c0 \u0110\u1ea4U N\u1ed0I"},"content":{"rendered":"

C\u00e1p quang d\u00f9ng \u00e1nh s\u00e1ng truy\u1ec1n d\u1eabn t\u00edn hi\u1ec7u, do \u0111\u00f3 \u00edt suy hao v\u00e0 th\u01b0\u1eddng \u0111\u01b0\u1ee3c d\u00f9ng cho k\u1ebft n\u1ed1i kho\u1ea3ng c\u00e1ch xa. Ng\u00e0y nay, Internet \u0111\u00e3 tr\u1edf th\u00e0nh m\u1ed9t nhu c\u1ea7u thi\u1ebft y\u1ebfu, gi\u00fap m\u1ecdi ng\u01b0\u1eddi \u1edf kh\u1eafp n\u01a1i tr\u00ean th\u1ebf gi\u1edbi c\u00f3 th\u1ec3 giao ti\u1ebfp, trao \u0111\u1ed5i, h\u1ecdc t\u1eadp, mua s\u1eafm, gi\u1ea3i tr\u00ed d\u1ec5 d\u00e0ng, nhanh ch\u00f3ng. C\u00e1c \u1ee9ng d\u1ee5ng, d\u1ecbch v\u1ee5 tr\u00ean Internet c\u0169ng ng\u00e0y c\u00e0ng ph\u00e1t tri\u1ec3n theo, \u0111i\u1ec1u n\u00e0y \u0111\u00f2i h\u1ecfi t\u1ed1c \u0111\u1ed9, b\u0103ng th\u00f4ng k\u1ebft n\u1ed1i Internet cao v\u00e0 c\u00e1p quang tr\u1edf th\u00e0nh l\u1ef1a ch\u1ecdn s\u1ed1 m\u1ed9t – FTTH (Fiber To Home) l\u00e0 m\u1ed9t \u0111i\u1ec3n h\u00ecnh. FTTH \u0111\u00e1p \u1ee9ng c\u00e1c d\u1ecbch v\u1ee5 lu\u00f4n \u0111\u00f2i h\u1ecfi m\u1ea1ng k\u1ebft n\u1ed1i t\u1ed1c \u0111\u1ed9 cao nh\u01b0 IPTV, h\u1ed9i ngh\u1ecb truy\u1ec1n h\u00ecnh, video tr\u1ef1c tuy\u1ebfn, gi\u00e1m s\u00e1t t\u1eeb xa IP Camera…<\/p>\n

Tr\u01b0\u1edbc \u0111\u00e2y, c\u00e1p quang ch\u1ec9 d\u00f9ng \u0111\u1ec3 k\u1ebft n\u1ed1i c\u00e1c \u0111\u01b0\u1eddng tr\u1ee5c ch\u00ednh c\u1ee7a qu\u1ed1c gia, nh\u00e0 cung c\u1ea5p d\u1ecbch v\u1ee5, doanh nghi\u1ec7p l\u1edbn v\u00ec chi ph\u00ed kh\u00e1 cao. Nh\u01b0ng hi\u1ec7n nay, c\u00e1p quang \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng kh\u00e1 r\u1ed9ng r\u00e3i \u1edf c\u00e1c doanh nghi\u1ec7p v\u1eeba, nh\u1ecf, c\u00e1c tr\u01b0\u1eddng \u0111\u1ea1i h\u1ecdc v\u00e0 ng\u01b0\u1eddi s\u1eed d\u1ee5ng th\u00f4ng th\u01b0\u1eddng. B\u00e0i vi\u1ebft gi\u1edbi thi\u1ec7u c\u01a1 b\u1ea3n v\u1ec1 c\u00e1p quang v\u00e0 c\u00e1c \u0111\u1ea7u n\u1ed1i, gi\u00fap b\u1ea1n \u0111\u1ecdc hi\u1ec3u \u0111\u01b0\u1ee3c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt tr\u00ean c\u00e1c t\u00e0i li\u1ec7u, th\u00f4ng tin s\u1ea3n ph\u1ea9m quang.<\/p>\n

C\u00e1p quang d\u00f9ng \u00e1nh s\u00e1ng truy\u1ec1n d\u1eabn t\u00edn hi\u1ec7u, do \u0111\u00f3 \u00edt suy hao v\u00e0 th\u01b0\u1eddng \u0111\u01b0\u1ee3c d\u00f9ng cho k\u1ebft n\u1ed1i kho\u1ea3ng c\u00e1ch xa. Trong khi c\u00e1p \u0111\u1ed3ng s\u1eed d\u1ee5ng d\u00f2ng \u0111i\u1ec7n \u0111\u1ec3 truy\u1ec1n t\u00edn hi\u1ec7u, d\u1ec5 b\u1ecb suy hao trong qu\u00e1 tr\u00ecnh truy\u1ec1n v\u00e0 c\u00f3 kho\u1ea3ng c\u00e1ch k\u1ebft n\u1ed1i ng\u1eafn h\u01a1n.<\/p>\n

S\u1ee3i c\u00e1p quang \u0111\u01b0\u1ee3c c\u1ea5u t\u1ea1o t\u1eeb ba th\u00e0nh ph\u1ea7n ch\u00ednh: l\u00f5i (core), l\u1edbp ph\u1ea3n x\u1ea1 \u00e1nh s\u00e1ng (cladding), l\u1edbp v\u1ecf b\u1ea3o v\u1ec7 ch\u00ednh (primary coating hay c\u00f2n g\u1ecdi coating, primary buffer).Core \u0111\u01b0\u1ee3c l\u00e0m b\u1eb1ng s\u1ee3i th\u1ee7y tinh ho\u1eb7c plastic d\u00f9ng truy\u1ec1n d\u1eabn \u00e1nh s\u00e1ng. Bao b\u1ecdc core l\u00e0 cladding – l\u1edbp th\u1ee7y tinh hay plastic – nh\u1eb1m b\u1ea3o v\u1ec7 v\u00e0 ph\u1ea3n x\u1ea1 \u00e1nh s\u00e1ng tr\u1edf l\u1ea1i core.Primary coating l\u00e0 l\u1edbp v\u1ecf nh\u1ef1a PVC gi\u00fap b\u1ea3o v\u1ec7 core v\u00e0 cladding kh\u00f4ng b\u1ecb b\u1ee5i, \u1ea9m, tr\u1ea7y x\u01b0\u1edbc. Hai lo\u1ea1i c\u00e1p quang ph\u1ed5 bi\u1ebfn l\u00e0 GOF (Glass Optical Fiber) – c\u00e1p quang l\u00e0m b\u1eb1ng thu\u1ef7 tinh v\u00e0 POF (Plastic Optical Fiber) – c\u00e1p quang l\u00e0m b\u1eb1ng plastic. POF c\u00f3 \u0111\u01b0\u1eddng k\u00ednh core kh\u00e1 l\u1edbn kho\u1ea3ng 1mm, s\u1eed d\u1ee5ng cho truy\u1ec1n d\u1eabn t\u00edn hi\u1ec7u kho\u1ea3ng c\u00e1ch ng\u1eafn, m\u1ea1ng t\u1ed1c \u0111\u1ed9 th\u1ea5p. Tr\u00ean c\u00e1c t\u00e0i li\u1ec7u k\u1ef9 thu\u1eadt, b\u1ea1n th\u01b0\u1eddng th\u1ea5y c\u00e1p quang GOF ghi c\u00e1c th\u00f4ng s\u1ed1 9\/125\u00b5m, 50\/125\u00b5m hay 62,5\/125\u00b5m, \u0111\u00e2y l\u00e0 \u0111\u01b0\u1eddng k\u00ednh c\u1ee7a core\/cladding; c\u00f2n primary coating c\u00f3 \u0111\u01b0\u1eddng k\u00ednh m\u1eb7c \u0111\u1ecbnh l\u00e0 250\u00b5m.<\/p>\n

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B\u1ea3o v\u1ec7 s\u1ee3i c\u00e1p quang l\u00e0 l\u1edbp v\u1ecf ngo\u00e0i g\u1ed3m nhi\u1ec1u l\u1edbp kh\u00e1c nhau t\u00f9y theo c\u1ea5u t\u1ea1o, t\u00ednh ch\u1ea5t c\u1ee7a m\u1ed7i lo\u1ea1i c\u00e1p. Nh\u01b0ng c\u00f3 ba l\u1edbp b\u1ea3o v\u1ec7 ch\u00ednh l\u00e0 l\u1edbp ch\u1ecbu l\u1ef1c k\u00e9o (strength member), l\u1edbp v\u1ecf b\u1ea3o v\u1ec7 ngo\u00e0i (buffer) v\u00e0 l\u1edbp \u00e1o gi\u00e1p (jacket) – t\u00f9y theo t\u00e0i li\u1ec7u s\u1ebd c\u00f3 t\u00ean g\u1ecdi kh\u00e1c nhau. Strength member l\u00e0 l\u1edbp ch\u1ecbu nhi\u1ec7t, ch\u1ecbu k\u00e9o c\u0103ng, th\u01b0\u1eddng l\u00e0m t\u1eeb c\u00e1c s\u1ee3i Kevlar.Buffer th\u01b0\u1eddng l\u00e0m b\u1eb1ng nh\u1ef1a PVC, b\u1ea3o v\u1ec7 tr\u00e1nh va \u0111\u1eadp, \u1ea9m \u01b0\u1edbt. L\u1edbp b\u1ea3o v\u1ec7 ngo\u00e0i c\u00f9ng l\u00e0 Jacket. M\u1ed7i lo\u1ea1i c\u00e1p, t\u00f9y theo y\u00eau c\u1ea7u s\u1eed d\u1ee5ng s\u1ebd c\u00f3 th\u00eam c\u00e1c l\u1edbp jacket kh\u00e1c nhau.Jacket c\u00f3 kh\u1ea3 n\u0103ng ch\u1ecbu va \u0111\u1eadp, nhi\u1ec7t v\u00e0 ch\u1ecbu m\u00e0i m\u00f2n, b\u1ea3o v\u1ec7 ph\u1ea7n b\u00ean trong tr\u00e1nh \u1ea9m \u01b0\u1edbt v\u00e0 c\u00e1c \u1ea3nh h\u01b0\u1edfng t\u1eeb m\u00f4i tr\u01b0\u1eddng.<\/p>\n

C\u00f3 hai c\u00e1ch thi\u1ebft k\u1ebf kh\u00e1c nhau \u0111\u1ec3 b\u1ea3o v\u1ec7 s\u1ee3i c\u00e1p quang l\u00e0 \u1ed1ng \u0111\u1ec7m kh\u00f4ng ch\u1eb7t (loose-tube) v\u00e0 \u1ed1ng \u0111\u1ec7m ch\u1eb7t (tight buffer).<\/p>\n

Loose-tube th\u01b0\u1eddng d\u00f9ng ngo\u00e0i tr\u1eddi (outdoor), cho ph\u00e9p ch\u1ee9a nhi\u1ec1u s\u1ee3i quang b\u00ean trong. Loose-tube gi\u00fap s\u1ee3i c\u00e1p quang \u201cgi\u00e3n n\u1edf\u201d tr\u01b0\u1edbc s\u1ef1 thay \u0111\u1ed5i nhi\u1ec7t \u0111\u1ed9, co gi\u00e3n t\u1ef1 nhi\u00ean, kh\u00f4ng b\u1ecb c\u0103ng, b\u1ebb g\u1eadp \u1edf nh\u1eefng ch\u1ed7 cong.<\/p>\n

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Tight-buffer th\u01b0\u1eddng d\u00f9ng trong nh\u00e0 (indoor), bao b\u1ecdc kh\u00edt s\u1ee3i c\u00e1p quang (nh\u01b0 c\u00e1p \u0111i\u1ec7n), gi\u00fap d\u1ec5 l\u1eafp \u0111\u1eb7t khi thi c\u00f4ng.<\/p>\n

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Tr\u00ean m\u1ed9t s\u1ed1 t\u00e0i li\u1ec7u, b\u1ea1n s\u1ebd g\u1eb7p hai thu\u1eadt ng\u1eef vi\u1ebft t\u1eaft IFC, OSP. IFC (Intrafacility fiber cable) l\u00e0 lo\u1ea1i c\u00e1p d\u00f9ng trong nh\u00e0, c\u00f3 \u00edt l\u1edbp b\u1ea3o v\u1ec7 v\u1eadt l\u00fd v\u00e0 vi\u1ec7c thi c\u00f4ng l\u1eafp \u0111\u1eb7t linh ho\u1ea1t.OSP (Outside plant cable) l\u00e0 lo\u1ea1i c\u00e1p d\u00f9ng ngo\u00e0i tr\u1eddi, ch\u1ecbu \u0111\u01b0\u1ee3c nh\u1eefng \u0111i\u1ec1u ki\u1ec7n kh\u1eafc nghi\u1ec7t c\u1ee7a nhi\u1ec7t \u0111\u1ed9, \u0111\u1ed9 \u1ea9m, b\u1ee5i… lo\u1ea1i c\u00e1p n\u00e0y c\u00f3 nhi\u1ec1u l\u1edbp b\u1ea3o v\u1ec7.<\/p>\n

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C\u00e1c tia s\u00e1ng b\u00ean trong c\u00e1p quang c\u00f3 hai ki\u1ec3u truy\u1ec1n d\u1eabn l\u00e0 \u0111\u01a1n m\u1ed1t (Singlemode) v\u00e0 \u0111a m\u1ed1t (Multimode). C\u00e1p quangSinglemode (SM) c\u00f3 \u0111\u01b0\u1eddng k\u00ednh core kh\u00e1 nh\u1ecf (kho\u1ea3ng 9\u00b5m), s\u1eed d\u1ee5ng ngu\u1ed3n ph\u00e1t laser truy\u1ec1n tia s\u00e1ng xuy\u00ean su\u1ed1t v\u00ec v\u1eady t\u00edn hi\u1ec7u \u00edt b\u1ecb suy hao v\u00e0 c\u00f3 t\u1ed1c \u0111\u1ed9 kh\u00e1 l\u1edbn. SM th\u01b0\u1eddng ho\u1ea1t \u0111\u1ed9ng \u1edf 2 b\u01b0\u1edbc s\u00f3ng (wavelength) 1310nm, 1550nm. C\u00e1p quang Multimode (MM) c\u00f3 \u0111\u01b0\u1eddng k\u00ednh core l\u1edbn h\u01a1n SM (kho\u1ea3ng 50\u00b5m, 62.5\u00b5m). MM s\u1eed d\u1ee5ng ngu\u1ed3n s\u00e1ng LED (Light Emitting Diode) ho\u1eb7c laser \u0111\u1ec3 truy\u1ec1n tia s\u00e1ng v\u00e0 th\u01b0\u1eddng ho\u1ea1t \u0111\u1ed9ng \u1edf 2 b\u01b0\u1edbc s\u00f3ng 850nm, 1300nm; MM c\u00f3 kho\u1ea3ng c\u00e1ch k\u1ebft n\u1ed1i v\u00e0 t\u1ed1c \u0111\u1ed9 truy\u1ec1n d\u1eabn nh\u1ecf h\u01a1n SM.<\/p>\n

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MM c\u00f3 hai ki\u1ec3u truy\u1ec1n: chi\u1ebft xu\u1ea5t b\u01b0\u1edbc (Step index) v\u00e0 chi\u1ebft xu\u1ea5t li\u00ean t\u1ee5c (Graded index). C\u00e1c tia s\u00e1ng ki\u1ec3u Step index truy\u1ec1n theo nhi\u1ec1u h\u01b0\u1edbng kh\u00e1c nhau v\u00ec v\u1eady c\u00f3 m\u1ee9c suy hao cao v\u00e0 t\u1ed1c \u0111\u1ed9 kh\u00e1 ch\u1eadm. Step index \u00edt ph\u1ed5 bi\u1ebfn, th\u01b0\u1eddng d\u00f9ng cho c\u00e1p quang POF. C\u00e1c tia s\u00e1ng ki\u1ec3u Graded index truy\u1ec1n d\u1eabn theo \u0111\u01b0\u1eddng cong v\u00e0 h\u1ed9i t\u1ee5 t\u1ea1i m\u1ed9t \u0111i\u1ec3m. Do \u0111\u00f3 Graded index \u00edt suy hao v\u00e0 c\u00f3 t\u1ed1c \u0111\u1ed9 truy\u1ec1n d\u1eabn cao h\u01a1n Step index. Graded index \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng kh\u00e1 ph\u1ed5 bi\u1ebfn.<\/p>\n

Truy\u1ec1n d\u1eabn t\u00edn hi\u1ec7u tr\u00ean c\u00e1p quang c\u00f3 hai d\u1ea1ng \u0111\u01a1n c\u00f4ng (simplex) v\u00e0 song c\u00f4ng (duplex). Simplex truy\u1ec1n t\u00edn hi\u1ec7u ch\u1ec9 1 chi\u1ec1u. Duplex c\u00f3 th\u1ec3 truy\u1ec1n nh\u1eadn t\u00edn hi\u1ec7u 1 chi\u1ec1u b\u00e1n song c\u00f4ng (half-Duplex) ho\u1eb7c c\u1ea3 2 chi\u1ec1u song c\u00f4ng to\u00e0n ph\u1ea7n (full-Duplex) Duplex \u1edf c\u00f9ng th\u1eddi \u0111i\u1ec3m t\u00f9y theo c\u00e1ch c\u1ea5u h\u00ecnh.<\/p>\n

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\u0110\u1ec3 \u0111\u1ea5u n\u1ed1i c\u00e1p quang v\u00e0o b\u1ea3ng \u0111\u1ea5u d\u00e2y (patch panel) ho\u1eb7c v\u00e0o c\u00e1c c\u1ed5ng v\u00e0o\/ra (input\/output) tr\u00ean c\u00e1c thi\u1ebft b\u1ecb truy\u1ec1n nh\u1eadn quang, ng\u01b0\u1eddi ta th\u01b0\u1eddng s\u1eed d\u1ee5ng d\u00e2y n\u1ed1i quang m\u1ed9t \u0111\u1ea7u c\u00f3 s\u1eb5n \u0111\u1ea7u n\u1ed1i (pigtail) ho\u1eb7c c\u1ea3 hai \u0111\u1ea7u c\u00f3 s\u1eb5n \u0111\u1ea7u n\u1ed1i (pathcord).<\/p>\n

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M\u1ed9t s\u1ed1 lo\u1ea1i c\u00e1p quang:<\/strong><\/p>\n

Ribbon:<\/strong><\/em>\u00a0C\u00e1p\u00a0quang d\u1ea1ng ruy-b\u0103ng, ch\u1ee9a nhi\u1ec1u s\u1ee3i quang b\u00ean trong.<\/p>\n

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Zipcord:<\/strong><\/em>\u00a0hai s\u1ee3i quang c\u00f3 v\u1ecf ngo\u00e0i li\u1ec1n nhau (nh\u01b0 d\u00e2y \u0111i\u1ec7n).<\/p>\n

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B\u1ea5t k\u1ef3 giao ti\u1ebfp quang n\u00e0o c\u0169ng bao g\u1ed3m 3 th\u00e0nh ph\u1ea7n: ngu\u1ed3n ph\u00e1t, v\u1eadt truy\u1ec1n d\u1eabn trung gian (c\u00e1p quang) v\u00e0 ngu\u1ed3n thu. Ngu\u1ed3n ph\u00e1t s\u1ebd chuy\u1ec3n \u0111\u1ed5i t\u00edn hi\u1ec7u \u0111i\u1ec7n t\u1eed th\u00e0nh \u00e1nh s\u00e1ng v\u00e0 truy\u1ec1n d\u1eabn qua c\u00e1p quang. Ngu\u1ed3n thu chuy\u1ec3n \u0111\u1ed5i \u00e1nh s\u00e1ng th\u00e0nh t\u00edn hi\u1ec7u \u0111i\u1ec7n t\u1eed. C\u00f3 hai lo\u1ea1i ngu\u1ed3n ph\u00e1t l\u00e0 laser v\u00e0 LED. Laser \u00edt t\u00e1n s\u1eafc, cho ph\u00e9p truy\u1ec1n d\u1eabn d\u1eef li\u1ec7u t\u1ed1c \u0111\u1ed9 nhanh, kho\u1ea3ng c\u00e1ch xa (tr\u00ean 20km), d\u00f9ng \u0111\u01b0\u1ee3c cho c\u1ea3 Singlemode v\u00e0 Multimode nh\u01b0ng chi ph\u00ed cao, kh\u00f3 s\u1eed d\u1ee5ng. LED t\u00e1n s\u1eafc nhi\u1ec1u, truy\u1ec1n d\u1eabn t\u1ed1c \u0111\u1ed9 ch\u1eadm h\u01a1n, b\u00f9 l\u1ea1i chi ph\u00ed th\u1ea5p, d\u1ec5 s\u1eed d\u1ee5ng, th\u01b0\u1eddng d\u00f9ng cho c\u00e1p quang Multimode. LED d\u00f9ng cho h\u1ec7 th\u1ed1ng c\u00f3 kho\u1ea3ng c\u00e1ch ng\u1eafn h\u01a1n, c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng cho c\u1ea3 s\u1ee3i quang th\u1ee7y tinh, s\u1ee3i quang plastic.<\/p>\n

C\u00e1c th\u00f4ng s\u1ed1 quang c\u1ea7n quan t\u00e2m<\/strong><\/p>\n

Suy hao quang (Optical loss): l\u01b0\u1ee3ng c\u00f4ng su\u1ea5t quang (optical power) m\u1ea5t trong su\u1ed1t qu\u00e1 tr\u00ecnh truy\u1ec1n d\u1eabn qua c\u00e1p quang, \u0111i\u1ec3m gh\u00e9p n\u1ed1i. K\u00fd hi\u1ec7u dB.<\/p>\n

Suy hao ph\u1ea3n x\u1ea1 (Optical Return loss): \u00e1nh s\u00e1ng b\u1ecb ph\u1ea3n x\u1ea1 t\u1ea1i c\u00e1c \u0111i\u1ec3m gh\u00e9p n\u1ed1i, \u0111\u1ea7u n\u1ed1i quang.<\/p>\n

Suy hao ti\u1ebfp x\u00fac (Insertion loss): gi\u1ea3m c\u00f4ng su\u1ea5t quang \u1edf hai \u0111\u1ea7u gh\u00e9p n\u1ed1i. Gi\u00e1 tr\u1ecb th\u00f4ng th\u01b0\u1eddng t\u1eeb 0,2dB – 0,5dB.<\/p>\n

Suy hao (Attenuation): m\u1ee9c suy gi\u1ea3m c\u00f4ng su\u1ea5t quang trong su\u1ed1t qu\u00e1 tr\u00ecnh truy\u1ec1n d\u1eabn tr\u00ean m\u1ed9t kho\u1ea3ng c\u00e1ch x\u00e1c \u0111\u1ecbnh. K\u00fd hi\u1ec7u dB\/km. V\u00ed d\u1ee5, v\u1edbi c\u00e1p quang Multimode \u1edf b\u01b0\u1edbc s\u00f3ng 850nm suy gi\u1ea3m 3dB\/km, trong khi \u1edf b\u01b0\u1edbc s\u00f3ng 1300nm ch\u1ec9 suy gi\u1ea3m 1dB\/km. C\u00e1p quang Singlemode: suy gi\u1ea3m 0,4dB\/km \u1edf 1310nm, 0,3dB\/km \u1edf 1550nm. \u0110\u1ea7u n\u1ed1i (connector) suy gi\u1ea3m 0,5dB\/c\u1eb7p \u0111\u1ea5u n\u1ed1i. \u0110i\u1ec3m gh\u00e9p n\u1ed1i (splice) suy gi\u1ea3m 0,2 dB\/\u0111i\u1ec3m.<\/p>\n

B\u01b0\u1edbc s\u00f3ng (Wavelength): l\u00e0 chu k\u1ef3 di chuy\u1ec3n c\u1ee7a s\u00f3ng \u0111i\u1ec7n t\u1eeb. K\u00fd hi\u1ec7u nm (nanometer). \u00c1nh s\u00e1ng ch\u00fang ta nh\u00ecn th\u1ea5y \u0111\u01b0\u1ee3c c\u00f3 wavelength t\u1eeb 400nm \u0111\u1ebfn 700nm (m\u00e0u t\u00edm \u0111\u1ebfn m\u00e0u \u0111\u1ecf). C\u00e1p quang s\u1eed d\u1ee5ng \u00e1nh s\u00e1ng n\u1eb1m trong v\u00f9ng h\u1ed3ng ngo\u1ea1i c\u00f3 wavelength l\u1edbn h\u01a1n wavelength m\u00e0 ta nh\u00ecn th\u1ea5y \u2013 trong kho\u1ea3ng 850nm, 1300nm v\u00e0 1550nm. C\u00e1c b\u01b0\u1edbc s\u00f3ng truy\u1ec1n d\u1eabn quang \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh d\u1ef1a tr\u00ean hai y\u1ebfu t\u1ed1 nh\u1eb1m kh\u1eafc ph\u1ee5c t\u00ecnh tr\u1ea1ng suy hao do n\u0103ng l\u01b0\u1ee3ng v\u00e0 v\u1eadt li\u1ec7u truy\u1ec1n d\u1eabn: c\u00e1c b\u01b0\u1edbc s\u00f3ng n\u1eb1m trong v\u00f9ng h\u1ed3ng ngo\u1ea1i v\u00e0 c\u00e1c b\u01b0\u1edbc s\u00f3ng kh\u00f4ng n\u1eb1m trong v\u00f9ng h\u1ea5p thu, c\u1ea3n tr\u1edf n\u0103ng l\u01b0\u1ee3ng \u00e1nh s\u00e1ng truy\u1ec1n d\u1eabn (absorption) do t\u1ea1p ch\u1ea5t l\u1eabn trong c\u00e1p quang t\u1eeb qu\u00e1 tr\u00ecnh s\u1ea3n xu\u1ea5t.<\/p>\n

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V\u1eady v\u00ec sao ch\u00fang ta kh\u00f4ng s\u1eed d\u1ee5ng c\u00e1c b\u01b0\u1edbc s\u00f3ng d\u00e0i h\u01a1n? B\u01b0\u1edbc s\u00f3ng h\u1ed3ng ngo\u1ea1i l\u00e0 s\u1ef1 chuy\u1ec3n ti\u1ebfp gi\u1eefa \u00e1nh s\u00e1ng v\u00e0 nhi\u1ec7t. B\u01b0\u1edbc s\u00f3ng d\u00e0i h\u01a1n, nhi\u1ec7t xung quang c\u00e0ng n\u00f3ng h\u01a1n, t\u00edn hi\u1ec7u nhi\u1ec5u lo\u1ea1n nhi\u1ec1u h\u01a1n. Do \u0111\u00f3, th\u01b0\u1eddng POF c\u00f3 b\u01b0\u1edbc s\u00f3ng 650nm, 850nm. GOF v\u1edbi Multimode ho\u1ea1t \u0111\u1ed9ng \u1edf 850nm v\u00e0 1300nm, Singlemode \u1edf 1310nm, 1550nm. Gi\u1eefa hai b\u01b0\u1edbc s\u00f3ng 1300nm v\u00e0 1310nm kh\u00f4ng kh\u00e1c bi\u1ec7t nhau, ch\u1ec9 l\u00e0 c\u00e1ch qui \u01b0\u1edbc \u0111\u1ec3 ph\u00e2n bi\u1ec7t s\u1eed d\u1ee5ng c\u00e1p quang Singlemode hay Multimode.<\/p>\n

\u0110\u1ea7u n\u1ed1i quang: g\u1ed3m nhi\u1ec1u th\u00e0nh ph\u1ea7n k\u1ebft h\u1ee3p l\u1ea1i v\u1edbi nhau, ch\u00fang c\u00f3 nhi\u1ec1u ki\u1ec3u nh\u01b0 SC\/PC, ST\/UPC, FC\/APC… Nh\u01b0ng c\u00f3 hai th\u00e0nh ph\u1ea7n b\u1ea1n c\u1ea7n quan t\u00e2m, \u0111\u00f3 l\u00e0 ki\u1ec3u \u0111\u1ea7u n\u1ed1i SC, ST, FC…v\u00e0 \u0111i\u1ec3m ti\u1ebfp x\u00fac PC, UPC, APC.<\/p>\n

SC (subscriber connector), ST (straight tip), FC (fiber connector) l\u00e0 c\u00e1c ki\u1ec3u \u0111\u1ea7u n\u1ed1i quang c\u00f3 d\u1ea1ng h\u00ecnh vu\u00f4ng, h\u00ecnh tr\u00f2n..<\/p>\n

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B\u00ean trong \u0111\u1ea7u n\u1ed1i l\u00e0 ferrule, gi\u00fap b\u1ea3o v\u1ec7 v\u00e0 gi\u1eef th\u1eb3ng s\u1ee3i c\u00e1p quang. Ferrule \u0111\u01b0\u1ee3c l\u00e0m b\u1eb1ng th\u1ee7y tinh, kim lo\u1ea1i, plastic ho\u1eb7c g\u1ed1m (ceramic) – trong \u0111\u00f3 ch\u1ea5t li\u1ec7u g\u1ed1m l\u00e0 t\u1ed1t nh\u1ea5t.<\/p>\n

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\u0110\u1ec9nh c\u1ee7a ferrule \u0111\u01b0\u1ee3c l\u00e0m nh\u1eb5n (polish) v\u1edbi ba d\u1ea1ng \u0111i\u1ec3m ti\u1ebfp x\u00fac ch\u00ednh PC (Physical Contact), UPC (Ultra Physical Contact) v\u00e0 APC (Angled Physical Contact), gi\u00fap \u0111\u1ea3m b\u1ea3o ch\u1ed7 gh\u00e9p n\u1ed1i c\u00f3 \u00edt \u00e1nh s\u00e1ng b\u1ecb m\u1ea5t ho\u1eb7c b\u1ecb ph\u1ea3n x\u1ea1 nh\u1ea5t.<\/p>\n

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D\u1ea1ng PC \u0111\u01b0\u1ee3c v\u1ea1t cong, s\u1eed d\u1ee5ng v\u1edbi c\u00e1c ki\u1ec3u \u0111\u1ea7u n\u1ed1i FC, SC, ST. PC, c\u00f3 gi\u00e1 tr\u1ecb suy hao ph\u1ea3n x\u1ea1 (optical return loss) l\u00e0 40dB. V\u00ec gi\u00e1 tr\u1ecb n\u00e0y kh\u00e1 cao, n\u00ean \u0111\u00e3 th\u00fac \u0111\u1ea9y c\u00e1c nh\u00e0 s\u1ea3n xu\u1ea5t ti\u1ebfp t\u1ee5c t\u00ecm ki\u1ebfm c\u00e1c gi\u1ea3i ph\u00e1p t\u1ed1t h\u01a1n. UPC l\u00e0 gi\u1ea3i ph\u00e1p ti\u1ebfp theo, n\u00f3 c\u0169ng \u0111\u01b0\u1ee3c v\u1ea1t cong nh\u01b0 PC nh\u01b0ng gi\u1ea3m return loss h\u01a1n. UPC c\u00f3 gi\u00e1 tr\u1ecb return loss 50dB. UPC d\u00f9ng v\u1edbi c\u00e1c \u0111\u1ea7u n\u1ed1i FC, SC, ST, DIN, E2000. APC \u0111\u01b0\u1ee3c v\u1ea1t ch\u00e9o 8 \u0111\u1ed9\u00ad\u00ad, lo\u1ea1i b\u1ecf h\u1ea7u h\u1ebft s\u1ef1 ph\u1ea3n x\u1ea1 \u1edf \u0111i\u1ec3m gh\u00e9p n\u1ed1i v\u00e0 c\u00f3 gi\u00e1 tr\u1ecb return loss 60dB. B\u1ea1n n\u00ean l\u01b0u \u00fd l\u00e0 khi \u0111\u1ecdc c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt quang \u0111\u1ec1 c\u1eadp m\u1ee9c suy hao c\u00f3 th\u1ec3 l\u00e0m b\u1ea1n d\u1ec5 hi\u1ec3u sai v\u1ec1 d\u1ea5u \u201c+\u201d v\u00e0 \u201c-\u201c. Ch\u1eb3ng h\u1ea1n, v\u1edbi k\u1ebft qu\u1ea3 t\u00ednh to\u00e1n, \u0111o \u0111\u1ea1c m\u1ee9c \u0111\u1ed9 suy hao l\u00e0 -40dB. Tr\u00ean th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u00f3 th\u1ec3 vi\u1ebft gi\u00e1 tr\u1ecb suy hao (loss values) l\u00e0 40dB ho\u1eb7c s\u1ed1 \u0111o m\u1ee9c ph\u1ea3n x\u1ea1 l\u00e0 -40dB hay \u0111\u1ed9 l\u1ee3i (gain) l\u00e0 -40dB. T\u1ea5t c\u1ea3 \u0111\u1ec1u nh\u01b0 nhau, do \u0111\u00f3 b\u1ea1n c\u1ea7n ch\u00fa \u00fd c\u00e1ch vi\u1ebft \u0111\u1ec3 tr\u00e1nh hi\u1ec3u sai.<\/p>\n

Hi\u1ec7n nay, gi\u00e1 th\u00e0nh c\u00e1p quang v\u00e0 c\u00e1c ph\u1ee5 ki\u1ec7n quang \u0111\u00e3 th\u1ea5p h\u01a1n so v\u1edbi c\u00e1ch nay v\u00e0i n\u0103m. C\u00f9ng v\u1edbi vi\u1ec7c \u1ee9ng d\u1ee5ng nhi\u1ec1u gi\u1ea3i ph\u00e1p nh\u01b0 IP Camera, VoIP, H\u1ed9i ngh\u1ecb truy\u1ec1n h\u00ecnh qua m\u1ea1ng, k\u1ebft n\u1ed1i m\u1ea1ng gigabit gi\u1eefa c\u00e1c t\u00f2a nh\u00e0, v\u0103n ph\u00f2ng, x\u01b0\u1edfng s\u1ea3n xu\u1ea5t; c\u00e1p quang d\u1ea7n tr\u1edf th\u00e0nh l\u1ef1a ch\u1ecdn s\u1ed1 m\u1ed9t cho vi\u1ec7c tri\u1ec3n khai h\u1ea1 t\u1ea7ng m\u1ea1ng \u0111\u00f2i h\u1ecfi nhi\u1ec1u b\u0103ng th\u00f4ng v\u00e0 t\u1ed1c \u0111\u1ed9 cao.<\/p>","protected":false},"featured_media":5976,"parent":0,"menu_order":0,"template":"","tags":[],"category-news":[102,103],"class_list":["post-5963","tin-tuc","type-tin-tuc","status-publish","has-post-thumbnail","hentry","category-news-tin-cong-nghe","category-news-tin-cong-ty"],"acf":[],"_links":{"self":[{"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/tin-tuc\/5963","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/tin-tuc"}],"about":[{"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/types\/tin-tuc"}],"version-history":[{"count":1,"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/tin-tuc\/5963\/revisions"}],"predecessor-version":[{"id":7352,"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/tin-tuc\/5963\/revisions\/7352"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/media\/5976"}],"wp:attachment":[{"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/media?parent=5963"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/tags?post=5963"},{"taxonomy":"category-news","embeddable":true,"href":"https:\/\/vinacap.vn\/zh\/wp-json\/wp\/v2\/category-news?post=5963"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}