{"id":2538,"date":"2026-04-10T00:00:00","date_gmt":"2026-04-10T00:00:00","guid":{"rendered":"https:\/\/lp.szlogic.cn\/glossary\/dispersion-compensation-fiber-dcf\/"},"modified":"2026-06-22T03:35:11","modified_gmt":"2026-06-22T03:35:11","slug":"dispersion-compensation-fiber-dcf","status":"publish","type":"post","link":"https:\/\/resourceslp.szlogic.cn\/vi\/glossary\/dispersion-compensation-fiber-dcf","title":{"rendered":"S\u1ee3i b\u00f9 t\u00e1n s\u1eafc (DCF): H\u01b0\u1edbng d\u1eabn \u0111\u1ea7y \u0111\u1ee7"},"content":{"rendered":"
\"Dispersion<\/figure>\n\n\n\n

S\u1ee3i b\u00f9 t\u00e1n s\u1eafc (DCF) l\u00e0 m\u1ed9t lo\u1ea1i s\u1ee3i quang chuy\u00ean d\u1ee5ng \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1ec3 b\u00f9 tr\u1eeb hi\u1ec7n t\u01b0\u1ee3ng t\u00e1n s\u1eafc s\u1eafc m\u00e0u trong \u0111\u01b0\u1eddng truy\u1ec1n. N\u00f3i m\u1ed9t c\u00e1ch \u0111\u01a1n gi\u1ea3n, n\u00f3 gi\u00fap hi\u1ec7u ch\u1ec9nh hi\u1ec7n t\u01b0\u1ee3ng gi\u00e3n n\u1edf xung x\u1ea3y ra khi \u00e1nh s\u00e1ng lan truy\u1ec1n qua s\u1ee3i quang, \u0111\u1eb7c bi\u1ec7t trong c\u00e1c h\u1ec7 th\u1ed1ng truy\u1ec1n d\u1eabn kho\u1ea3ng c\u00e1ch xa v\u00e0 gh\u00e9p k\u00eanh ph\u00e2n chia theo b\u01b0\u1edbc s\u00f3ng m\u1eadt \u0111\u1ed9 cao (DWDM<\/a>) h\u1ec7 th\u1ed1ng. Trong thi\u1ebft k\u1ebf m\u1ea1ng hi\u1ec7n \u0111\u1ea1i, DCF th\u01b0\u1eddng \u0111\u01b0\u1ee3c b\u00e0n lu\u1eadn c\u00f9ng v\u1edbi m\u00f4-\u0111un b\u00f9 t\u00e1n s\u1eafc<\/a> (DCM) ho\u1eb7c m\u00f4-\u0111un b\u00f9 \u0111\u1ed9 d\u1ed1c t\u00e1n s\u1eafc (DSCM), v\u1ed1n \u0111\u00f3ng g\u00f3i ch\u1ee9c n\u0103ng n\u00e0y th\u00e0nh c\u00e1c \u0111\u01a1n v\u1ecb c\u00f3 th\u1ec3 tri\u1ec3n khai \u0111\u01b0\u1ee3c cho c\u00e1c \u0111\u01b0\u1eddng truy\u1ec1n kho\u1ea3ng c\u00e1ch xa.<\/p>\n\n\n\n

\u2705 S\u1ee3i b\u00f9 t\u00e1n s\u1eafc (DCF) l\u00e0 g\u00ec?<\/h2>\n\n\n\n
\"What<\/figure>\n\n\n\n

DCF l\u00e0 m\u1ed9t gi\u1ea3i ph\u00e1p qu\u1ea3n l\u00fd t\u00e1n s\u1eafc d\u1ef1a tr\u00ean s\u1ee3i quang, nh\u1eb1m t\u1ea1o ra t\u00e1n s\u1eafc s\u1eafc m\u00e0u \u00e2m \u0111\u1ec3 ch\u1ed1ng l\u1ea1i t\u00e1n s\u1eafc d\u01b0\u01a1ng t\u00edch l\u0169y trong s\u1ee3i truy\u1ec1n d\u1eabn ti\u00eau chu\u1ea9n. \u00dd t\u01b0\u1edfng c\u1ed1t l\u00f5i r\u1ea5t \u0111\u01a1n gi\u1ea3n: khi m\u1ed9t xung b\u1ecb k\u00e9o d\u00e0i trong m\u1ed9t s\u1ee3i, th\u00ec m\u1ed9t s\u1ee3i kh\u00e1c c\u00f3 \u0111\u1eb7c t\u00ednh t\u00e1n s\u1eafc ng\u01b0\u1ee3c l\u1ea1i c\u00f3 th\u1ec3 n\u00e9n xung \u0111\u00f3 tr\u1edf l\u1ea1i g\u1ea7n d\u1ea1ng ban \u0111\u1ea7u. ITU-T \u0111\u1ecbnh ngh\u0129a c\u00e1c th\u00f4ng s\u1ed1 tuy\u1ebfn t\u00ednh, x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 \u0111\u1eb7c tr\u01b0ng h\u00f3a s\u1ee3i \u0111\u01a1n mode v\u00e0 c\u00e1p, bao g\u1ed3m c\u1ea3 t\u00e1n s\u1eafc s\u1eafc m\u00e0u, trong khi DCF \u0111\u01b0\u1ee3c ch\u1ebf t\u1ea1o \u0111\u1eb7c bi\u1ec7t nh\u1eb1m ho\u1ea1t \u0111\u1ed9ng ch\u1ed1ng l\u1ea1i th\u00f4ng s\u1ed1 n\u00e0y trong b\u1ed1i c\u1ea3nh h\u1ec7 th\u1ed1ng.<\/p>\n\n\n\n

Tr\u00ean th\u1ef1c t\u1ebf, DCF kh\u00f4ng ch\u1ec9 l\u00e0 m\u1ed9t lo\u1ea1i s\u1ee3i mang t\u00ednh l\u00fd thuy\u1ebft; n\u00f3 th\u01b0\u1eddng \u0111\u01b0\u1ee3c tri\u1ec3n khai nh\u01b0 m\u1ed9t ph\u1ea7n c\u1ee7a m\u00f4-\u0111un \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong h\u1ec7 th\u1ed1ng truy\u1ec1n d\u1eabn quang kho\u1ea3ng c\u00e1ch xa. Lightera m\u00f4 t\u1ea3 c\u00e1c m\u00f4-\u0111un b\u00f9 t\u00e1n s\u1eafc nh\u01b0 m\u1ed9t ph\u1ea3n \u1ee9ng \u0111\u1ed1i v\u1edbi kho\u1ea3ng c\u00e1ch truy\u1ec1n d\u1eabn d\u00e0i h\u01a1n, b\u0103ng th\u00f4ng cao h\u01a1n v\u00e0 t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u cao h\u01a1n d\u1eef li\u1ec7u<\/a>, \u0111\u1ed3ng th\u1eddi l\u01b0u \u00fd r\u1eb1ng nh\u1eefng m\u00f4-\u0111un n\u00e0y \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf d\u00e0nh ri\u00eang cho c\u00e1c lo\u1ea1i s\u1ee3i truy\u1ec1n d\u1eabn ch\u00ednh. \u0110\u00f3 l\u00e0 l\u00fd do v\u00ec sao DCF v\u1eabn l\u00e0 m\u1ed9t thu\u1eadt ng\u1eef c\u00f3 \u00fd ngh\u0129a trong k\u1ef9 thu\u1eadt vi\u1ec5n th\u00f4ng, ngay c\u1ea3 khi nhi\u1ec1u h\u1ec7 th\u1ed1ng \u0111\u1ed3ng pha m\u1edbi h\u01a1n hi\u1ec7n nay ng\u00e0y c\u00e0ng ph\u1ee5 thu\u1ed9c nhi\u1ec1u h\u01a1n v\u00e0o c\u00e1c ph\u01b0\u01a1ng ph\u00e1p x\u1eed l\u00fd k\u1ef9 thu\u1eadt s\u1ed1.<\/p>\n\n\n\n

\u2705 T\u00e1n s\u1eafc s\u1eafc m\u00e0u \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn truy\u1ec1n d\u1eabn quang nh\u01b0 th\u1ebf n\u00e0o<\/h2>\n\n\n\n

T\u00e1n s\u1eafc s\u1eafc m\u00e0u<\/a> l\u00e0 m\u1ed9t trong nh\u1eefng suy hao v\u1eadt l\u00fd nghi\u00eam tr\u1ecdng nh\u1ea5t trong c\u00e1c h\u1ec7 th\u1ed1ng th\u00f4ng tin quang s\u1ee3i. Khi t\u1ed1c \u0111\u1ed9 truy\u1ec1n d\u1eabn v\u00e0 kho\u1ea3ng c\u00e1ch \u0111\u01b0\u1eddng truy\u1ec1n ti\u1ebfp t\u1ee5c t\u0103ng l\u00ean, t\u00e1c \u0111\u1ed9ng c\u1ee7a n\u00f3 \u0111\u1ed1i v\u1edbi \u0111\u1ed9 to\u00e0n v\u1eb9n t\u00edn hi\u1ec7u ng\u00e0y c\u00e0ng r\u00f5 r\u1ec7t. Vi\u1ec7c hi\u1ec3u r\u00f5 c\u00e1ch t\u00e1n s\u1eafc \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn t\u00edn hi\u1ec7u quang l\u00e0 \u0111i\u1ec1u thi\u1ebft y\u1ebfu \u0111\u1ec3 thi\u1ebft k\u1ebf c\u00e1c m\u1ea1ng t\u1ed1c \u0111\u1ed9 cao \u0111\u00e1ng tin c\u1eady v\u00e0 l\u1ef1a ch\u1ecdn \u0111\u00fang c\u00e1c c\u00f4ng ngh\u1ec7 b\u00f9 t\u00e1n s\u1eafc nh\u01b0 DCF.<\/p>\n\n\n\n

\"How<\/figure>\n\n\n\n

Nguy\u00ean nh\u00e2n g\u00e2y ra t\u00e1n s\u1eafc s\u1eafc m\u00e0u trong s\u1ee3i quang<\/h3>\n\n\n\n

T\u00e1n s\u1eafc s\u1eafc m\u00e0u x\u1ea3y ra do c\u00e1c b\u01b0\u1edbc s\u00f3ng kh\u00e1c nhau trong m\u1ed9t xung \u00e1nh s\u00e1ng di chuy\u1ec3n v\u1edbi v\u1eadn t\u1ed1c h\u01a1i kh\u00e1c nhau qua s\u1ee3i quang. S\u1ef1 bi\u1ebfn thi\u00ean v\u1eadn t\u1ed1c ph\u1ee5 thu\u1ed9c b\u01b0\u1edbc s\u00f3ng n\u00e0y d\u1eabn \u0111\u1ebfn s\u1ef1 lan r\u1ed9ng theo th\u1eddi gian c\u1ee7a t\u00edn hi\u1ec7u khi n\u00f3 lan truy\u1ec1n d\u1ecdc theo \u0111\u01b0\u1eddng truy\u1ec1n.<\/p>\n\n\n\n

Suy gi\u1ea3m t\u00edn hi\u1ec7u do hi\u1ec7n t\u01b0\u1ee3ng gi\u00e3n n\u1edf xung<\/h3>\n\n\n\n

Khi t\u00e1n s\u1eafc t\u00edch l\u0169y, xung quang gi\u00e3n n\u1edf v\u00e0 b\u1eaft \u0111\u1ea7u ch\u1ed3ng l\u1ea5n l\u00ean c\u00e1c xung li\u1ec1n k\u1ec1, m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 nhi\u1ec5u gi\u1eefa c\u00e1c k\u00fd hi\u1ec7u<\/a> (ISI). \u0110i\u1ec1u n\u00e0y l\u00e0m gi\u1ea3m \u0111\u1ed9 to\u00e0n v\u1eb9n t\u00edn hi\u1ec7u, gi\u1edbi h\u1ea1n kho\u1ea3ng c\u00e1ch truy\u1ec1n d\u1eabn v\u00e0 l\u00e0m t\u0103ng t\u1ef7 l\u1ec7 l\u1ed7i bit
<\/a>t\u1ef7 l\u1ec7 l\u1ed7i bit (BER), \u0111\u1eb7c bi\u1ec7t trong c\u00e1c h\u1ec7 th\u1ed1ng quang t\u1ed1c \u0111\u1ed9 cao.<\/p>\n\n\n\n

\u1ea2nh h\u01b0\u1edfng \u0111\u1ebfn b\u0103ng th\u00f4ng v\u00e0 kho\u1ea3ng c\u00e1ch truy\u1ec1n d\u1eabn<\/h3>\n\n\n\n

Hi\u1ec7n t\u01b0\u1ee3ng gi\u00e3n n\u1edf xung tr\u1ef1c ti\u1ebfp l\u00e0m gi\u1ea3m b\u0103ng th\u00f4ng s\u1eed d\u1ee5ng \u0111\u01b0\u1ee3c c\u1ee7a k\u00eanh quang. Trong truy\u1ec1n d\u1eabn kho\u1ea3ng c\u00e1ch xa, t\u00e1n s\u1eafc tr\u1edf th\u00e0nh y\u1ebfu t\u1ed1 gi\u1edbi h\u1ea1n then ch\u1ed1t, ki\u1ec1m ch\u1ebf c\u1ea3 t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u l\u1eabn ph\u1ea1m vi truy\u1ec1n d\u1eabn. N\u1ebfu kh\u00f4ng \u0111\u01b0\u1ee3c b\u00f9 tr\u1eeb th\u00edch h\u1ee3p, hi\u1ec7u n\u0103ng h\u1ec7 th\u1ed1ng s\u1ebd suy gi\u1ea3m nhanh ch\u00f3ng khi kho\u1ea3ng c\u00e1ch t\u0103ng l\u00ean.<\/p>\n\n\n\n

Vai tr\u00f2 c\u1ee7a c\u00e1c ti\u00eau chu\u1ea9n s\u1ee3i quang ITU-T trong qu\u1ea3n l\u00fd t\u00e1n s\u1eafc<\/h3>\n\n\n\n

C\u00e1c ti\u00eau chu\u1ea9n nh\u01b0 ITU-T G.652 quy \u0111\u1ecbnh s\u1ee3i \u0111\u01a1n mode th\u00f4ng th\u01b0\u1eddng v\u1edbi b\u01b0\u1edbc s\u00f3ng t\u00e1n s\u1eafc b\u1eb1ng kh\u00f4ng \u1edf kho\u1ea3ng 1310 nm<\/a>. Ng\u01b0\u1ee3c l\u1ea1i, ITU-T G.655 quy \u0111\u1ecbnh c\u00e1c lo\u1ea1i s\u1ee3i \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf v\u1edbi t\u00e1n s\u1eafc kh\u00e1c kh\u00f4ng c\u00f3 ki\u1ec3m so\u00e1t nh\u1eb1m gi\u1ea3m thi\u1ec3u c\u00e1c hi\u1ec7u \u1ee9ng phi tuy\u1ebfn nh\u01b0 hi\u1ec7n t\u01b0\u1ee3ng tr\u1ed9n b\u1ed1n s\u00f3ng trong c\u00e1c h\u1ec7 th\u1ed1ng DWDM.<\/p>\n\n\n\n

V\u00ec sao t\u00e1n s\u1eafc \u0111\u1eb7c bi\u1ec7t quan tr\u1ecdng trong c\u00e1c m\u1ea1ng DWDM<\/h3>\n\n\n\n

Trong c\u00e1c h\u1ec7 th\u1ed1ng gh\u00e9p k\u00eanh ph\u00e2n chia theo b\u01b0\u1edbc s\u00f3ng m\u1eadt \u0111\u1ed9 cao (DWDM), nhi\u1ec1u b\u01b0\u1edbc s\u00f3ng \u0111\u01b0\u1ee3c truy\u1ec1n \u0111\u1ed3ng th\u1eddi tr\u00ean m\u1ed9t s\u1ee3i quang duy nh\u1ea5t. \u0110i\u1ec1u n\u00e0y l\u00e0m t\u0103ng kh\u1ea3 n\u0103ng ch\u1ecbu \u1ea3nh h\u01b0\u1edfng b\u1edfi t\u00e1n s\u1eafc v\u00e0 c\u00e1c hi\u1ec7u \u1ee9ng phi tuy\u1ebfn, khi\u1ebfn vi\u1ec7c qu\u1ea3n l\u00fd t\u00e1n s\u1eafc ch\u00ednh x\u00e1c tr\u1edf n\u00ean thi\u1ebft y\u1ebfu \u0111\u1ec3 duy tr\u00ec ch\u1ea5t l\u01b0\u1ee3ng t\u00edn hi\u1ec7u v\u00e0 \u0111\u1ed9 \u1ed5n \u0111\u1ecbnh c\u1ee7a h\u1ec7 th\u1ed1ng.<\/p>\n\n\n\n

\u2705 C\u01a1 ch\u1ebf ho\u1ea1t \u0111\u1ed9ng c\u1ee7a DCF nh\u1eb1m ch\u1ed1ng l\u1ea1i t\u00e1n s\u1eafc s\u1ee3i quang<\/h2>\n\n\n\n

S\u1ee3i b\u00f9 t\u00e1n s\u1eafc (DCF) \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1eb7c bi\u1ec7t nh\u1eb1m trung h\u00f2a t\u00e1n s\u1eafc s\u1eafc m\u00e0u t\u00edch l\u0169y trong c\u00e1c h\u1ec7 th\u1ed1ng truy\u1ec1n d\u1eabn quang. B\u1eb1ng c\u00e1ch t\u1ea1o ra hi\u1ec7u \u1ee9ng t\u00e1n s\u1eafc ng\u01b0\u1ee3c (\u00e2m), DCF kh\u00f4i ph\u1ee5c \u0111\u1ed9 to\u00e0n v\u1eb9n t\u00edn hi\u1ec7u v\u00e0 cho ph\u00e9p t\u0103ng kho\u1ea3ng c\u00e1ch truy\u1ec1n d\u1eabn m\u00e0 kh\u00f4ng g\u00e2y suy gi\u1ea3m \u0111\u00e1ng k\u1ec3. Vi\u1ec7c hi\u1ec3u r\u00f5 c\u01a1 ch\u1ebf ho\u1ea1t \u0111\u1ed9ng c\u1ee7a n\u00f3 l\u00e0 \u0111i\u1ec1u thi\u1ebft y\u1ebfu \u0111\u1ec3 thi\u1ebft k\u1ebf c\u00e1c m\u1ea1ng quang DWDM v\u00e0 kho\u1ea3ng c\u00e1ch xa<\/a> hi\u1ec7u qu\u1ea3.<\/p>\n\n\n\n

\"How<\/figure>\n\n\n\n

Nguy\u00ean l\u00fd t\u00e1n s\u1eafc \u00e2m c\u1ee7a DCF<\/h3>\n\n\n\n

DCF ho\u1ea1t \u0111\u1ed9ng b\u1eb1ng c\u00e1ch cung c\u1ea5p h\u1ec7 s\u1ed1 t\u00e1n s\u1eafc \u00e2m l\u1edbn nh\u1eb1m ch\u1ed1ng l\u1ea1i t\u00e1n s\u1eafc d\u01b0\u01a1ng do s\u1ee3i truy\u1ec1n d\u1eabn ti\u00eau chu\u1ea9n sinh ra. M\u1ee5c ti\u00eau kh\u00f4ng \u0111\u01a1n thu\u1ea7n l\u00e0 gi\u1ea3m t\u00e1n s\u1eafc, m\u00e0 l\u00e0 c\u00e2n b\u1eb1ng t\u1ed5ng t\u00e1n s\u1eafc c\u1ee7a to\u00e0n b\u1ed9 \u0111\u01b0\u1eddng truy\u1ec1n \u1edf m\u1ee9c t\u1ed1i \u01b0u cho vi\u1ec7c truy\u1ec1n t\u00edn hi\u1ec7u.<\/p>\n\n\n\n

\n

D t\u1ed5ng = D truy\u1ec1n d\u1eabn + D DCF \u2248 0<\/strong><\/p>\n<\/blockquote>\n\n\n\n

Kh\u00e1i ni\u1ec7m \u201cc\u00e2n b\u1eb1ng\u201d trong thi\u1ebft k\u1ebf quang h\u1ecdc<\/h3>\n\n\n\n

M\u1ed9t c\u00e1ch hi\u1ec3u th\u1ef1c ti\u1ec5n v\u1ec1 DCF l\u00e0 xem n\u00f3 nh\u01b0 m\u1ed9t kh\u1ed1i \u201cc\u00e2n b\u1eb1ng\u201d trong \u0111\u01b0\u1eddng truy\u1ec1n quang. S\u1ee3i ti\u00eau chu\u1ea9n g\u00e2y ra m\u00e9o t\u00edn hi\u1ec7u do t\u00e1n s\u1eafc khi t\u00edn hi\u1ec7u lan truy\u1ec1n, trong khi DCF ch\u1ee7 \u0111\u1ed9ng t\u1ea1o ra m\u00e9o ng\u01b0\u1ee3c l\u1ea1i nh\u1eb1m tri\u1ec7t ti\u00eau hi\u1ec7u \u1ee9ng \u0111\u00f3.<\/p>\n\n\n\n

C\u00e1c nh\u00e0 thi\u1ebft k\u1ebf h\u1ec7 th\u1ed1ng t\u00ednh to\u00e1n m\u1ee9c b\u00f9 c\u1ea7n thi\u1ebft d\u1ef1a tr\u00ean:<\/p>\n\n\n\n