{"id":3823,"date":"2025-07-11T00:00:00","date_gmt":"2025-07-11T00:00:00","guid":{"rendered":"https:\/\/lp.szlogic.cn\/glossary\/understanding-non-return-to-zero-in-digital-communication\/"},"modified":"2026-06-22T09:05:11","modified_gmt":"2026-06-22T09:05:11","slug":"understanding-non-return-to-zero-in-digital-communication","status":"publish","type":"post","link":"https:\/\/resourceslp.szlogic.cn\/vi\/glossary\/understanding-non-return-to-zero-in-digital-communication","title":{"rendered":"T\u00ecm hi\u1ec3u v\u1ec1 ph\u01b0\u01a1ng ph\u00e1p m\u00e3 h\u00f3a Kh\u00f4ng quay v\u1ec1-zero (NRZ) trong truy\u1ec1n th\u00f4ng k\u1ef9 thu\u1eadt s\u1ed1"},"content":{"rendered":"<figure class=\"wp-block-image aligncenter size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1200\" height=\"712\" src=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/93798d823fa44865b84d2ba2aa74ec45.webp\" alt=\"Understanding Non-Return-to-Zero\" class=\"wp-image-3819\" srcset=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/93798d823fa44865b84d2ba2aa74ec45.webp 1200w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/93798d823fa44865b84d2ba2aa74ec45-300x178.webp 300w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/93798d823fa44865b84d2ba2aa74ec45-1024x608.webp 1024w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/93798d823fa44865b84d2ba2aa74ec45-768x456.webp 768w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/93798d823fa44865b84d2ba2aa74ec45-18x12.webp 18w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><span class=\"qc-p1-tag\" style=\"color: rgb(64, 64, 64);\">Trong th\u1ebf gi\u1edbi truy\u1ec1n th\u00f4ng k\u1ef9 thu\u1eadt s\u1ed1 \u0111\u1ea7y r\u1ee7i ro cao, n\u01a1i h\u00e0ng t\u1ef7 bit di chuy\u1ec3n qua c\u00e1c ch\u00e2u l\u1ee5c trong v\u00e0i miligi\u00e2y, ph\u01b0\u01a1ng ph\u00e1p c\u01a1 b\u1ea3n \u0111\u1ec3 bi\u1ec3u di\u1ec5n c\u00e1c bit 1 v\u00e0 0 \u0111\u00f3 tr\u1edf n\u00ean v\u00f4 c\u00f9ng quan tr\u1ecdng. H\u00e3y c\u00f9ng l\u00e0m quen v\u1edbi <\/span><span class=\"qc-p1-tag\"><strong>Kh\u00f4ng quay v\u1ec1-zero (NRZ)<\/strong><\/span><span class=\"qc-p1-tag\" style=\"color: rgb(64, 64, 64);\">, m\u1ed9t s\u01a1 \u0111\u1ed3 \u0111i\u1ec1u ch\u1ebf n\u1ec1n t\u1ea3ng \u0111\u00e3 th\u00fac \u0111\u1ea9y h\u00e0ng th\u1eadp k\u1ef7 truy\u1ec1n d\u1eabn d\u1eef li\u1ec7u, \u0111\u1eb7c bi\u1ec7t trong l\u0129nh v\u1ef1c then ch\u1ed1t c\u1ee7a <\/span><a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/store-25432-optics-transceivers-sfp-modules.htm\"><span class=\"qc-p1-tag\" style=\"color: var(--qc-color8);\"><strong>b\u1ed9 thu ph\u00e1t quang<\/strong><\/span><\/a><span class=\"qc-p1-tag\" style=\"color: rgb(64, 64, 64);\"> c\u00f4ng ngh\u1ec7. M\u1eb7c d\u00f9 nh\u1eefng s\u01a1 \u0111\u1ed3 ti\u00ean ti\u1ebfn h\u01a1n v\u00e0 ph\u1ee9c t\u1ea1p h\u01a1n \u0111ang xu\u1ea5t hi\u1ec7n \u0111\u1ec3 \u0111\u00e1p \u1ee9ng nhu c\u1ea7u b\u0103ng th\u00f4ng ng\u00e0y c\u00e0ng gia t\u0103ng, NRZ v\u1eabn gi\u1eef \u0111\u01b0\u1ee3c t\u00ednh li\u00ean quan \u0111\u00e1ng k\u1ec3, nh\u1edd v\u00e0o s\u1ef1 \u0111\u01a1n gi\u1ea3n, \u0111\u1ed9 tin c\u1eady v\u00e0 hi\u1ec7u qu\u1ea3 chi ph\u00ed cho nhi\u1ec1u \u1ee9ng d\u1ee5ng. Vi\u1ec7c hi\u1ec3u r\u00f5 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng, \u01b0u \u0111i\u1ec3m v\u00e0 h\u1ea1n ch\u1ebf c\u1ee7a n\u00f3 l\u00e0 \u0111i\u1ec1u thi\u1ebft y\u1ebfu \u0111\u1ed1i v\u1edbi b\u1ea5t k\u1ef3 ai thi\u1ebft k\u1ebf, tri\u1ec3n khai ho\u1eb7c qu\u1ea3n l\u00fd c\u00e1c m\u1ea1ng t\u1ed1c \u0111\u1ed9 cao.<\/span><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>\u27a4 L\u00e0m r\u00f5 t\u00edn hi\u1ec7u NRZ: S\u1ef1 \u0111\u01a1n gi\u1ea3n \u1edf c\u1ed1t l\u00f5i<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">H\u00e3y t\u01b0\u1edfng t\u01b0\u1ee3ng m\u1ed9t m\u1ee9c \u0111i\u1ec7n \u00e1p bi\u1ec3u th\u1ecb m\u1ed9t bit k\u1ef9 thu\u1eadt s\u1ed1. M\u00e3 h\u00f3a NRZ tu\u00e2n theo m\u1ed9t quy t\u1eafc h\u1ebft s\u1ee9c \u0111\u01a1n gi\u1ea3n:<\/p>\n\n\n\n<ol class=\"wp-block-list\" >\n<li><p style=\"margin: 0px;\"><strong>M\u1ee9c logic \u20181\u2019:<br><\/strong> \u0110\u01b0\u1ee3c bi\u1ec3u th\u1ecb b\u1eb1ng m\u1ee9c <em>cao<\/em> \u0111i\u1ec7n \u00e1p (v\u00ed d\u1ee5: +V).<\/p><\/li><li><p style=\"margin: 0px;\"><strong>M\u1ee9c logic \u20180\u2019:<br><\/strong> \u0110\u01b0\u1ee3c bi\u1ec3u th\u1ecb b\u1eb1ng m\u1ee9c <em>\u0111\u1ed9 tr\u1ec5 th\u1ea5p<\/em> m\u1ee9c \u0111i\u1ec7n \u00e1p (v\u00ed d\u1ee5: 0V ho\u1eb7c -V).<\/p><\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large\"><img decoding=\"async\" width=\"1200\" height=\"1100\" src=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/b5e05d70447a4b158361bb500e0679a9.webp\" alt=\"Non-Return-to-Zero (NRZ)\" class=\"wp-image-3821\" srcset=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/b5e05d70447a4b158361bb500e0679a9.webp 1200w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/b5e05d70447a4b158361bb500e0679a9-300x275.webp 300w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/b5e05d70447a4b158361bb500e0679a9-1024x939.webp 1024w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/b5e05d70447a4b158361bb500e0679a9-768x704.webp 768w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/b5e05d70447a4b158361bb500e0679a9-13x12.webp 13w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u0110\u1eb7c \u0111i\u1ec3m then ch\u1ed1t n\u1eb1m \u1edf ch\u00ednh t\u00ean g\u1ecdi c\u1ee7a n\u00f3: <strong>Kh\u00f4ng quay v\u1ec1 m\u1ee9c kh\u00f4ng<\/strong>. Kh\u00e1c v\u1edbi ti\u1ec1n th\u00e2n c\u1ee7a n\u00f3 l\u00e0 Return-to-Zero (RZ), t\u00edn hi\u1ec7u <em>kh\u00f4ng<\/em> quay tr\u1edf v\u1ec1 m\u1ee9c zero trung t\u00ednh gi\u1eefa hai bit li\u00ean ti\u1ebfp c\u00f3 c\u00f9ng gi\u00e1 tr\u1ecb. N\u1ebfu hai bit \u20181\u2019 \u0111\u1ee9ng li\u1ec1n nhau, \u0111i\u1ec7n \u00e1p s\u1ebd duy tr\u00ec \u1edf m\u1ee9c cao trong to\u00e0n b\u1ed9 th\u1eddi gian c\u1ee7a c\u1ea3 hai chu k\u1ef3 bit. T\u01b0\u01a1ng t\u1ef1, c\u00e1c bit \u20180\u2019 li\u00ean ti\u1ebfp s\u1ebd duy tr\u00ec m\u1ee9c \u0111i\u1ec7n \u00e1p th\u1ea5p.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">S\u1ef1 \u0111\u01a1n gi\u1ea3n n\u00e0y tr\u1ef1c ti\u1ebfp mang l\u1ea1i nh\u1eefng \u01b0u \u0111i\u1ec3m sau:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p style=\"margin: 0px;\"><strong>Y\u00eau c\u1ea7u b\u0103ng th\u00f4ng gi\u1ea3m:<\/strong> B\u1eb1ng c\u00e1ch tr\u00e1nh c\u00e1c chuy\u1ec3n \u0111\u1ed5i trung gian v\u1ec1 m\u1ee9c zero, NRZ chi\u1ebfm \u00edt b\u0103ng th\u00f4ng ph\u1ed5 h\u01a1n so v\u1edbi RZ \u1edf c\u00f9ng t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u. \u0110i\u1ec1u n\u00e0y r\u1ea5t hi\u1ec7u qu\u1ea3 cho c\u00e1c thi\u1ebft k\u1ebf <strong>b\u1ed9 thu ph\u00e1t quang<\/strong> .<\/p><\/li><li><p style=\"margin: 0px;\"><strong>\u0110\u1ed9 \u0111\u01a1n gi\u1ea3n trong tri\u1ec3n khai:<\/strong> B\u1ed9 ph\u00e1t v\u00e0 b\u1ed9 thu NRZ th\u01b0\u1eddng \u00edt ph\u1ee9c t\u1ea1p h\u01a1n trong thi\u1ebft k\u1ebf v\u00e0 s\u1ea3n xu\u1ea5t so v\u1edbi c\u00e1c s\u01a1 \u0111\u1ed3 ti\u00ean ti\u1ebfn h\u01a1n, g\u00f3p ph\u1ea7n gi\u1ea3m chi ph\u00ed v\u00e0 ti\u00eau th\u1ee5 \u0111i\u1ec7n n\u0103ng \u2014 nh\u1eefng y\u1ebfu t\u1ed1 then ch\u1ed1t trong c\u00e1c tri\u1ec3n khai quy m\u00f4 l\u1edbn nh\u01b0 trung t\u00e2m d\u1eef li\u1ec7u.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>\u0110\u1ed9 tin c\u1eady \u0111\u00e3 \u0111\u01b0\u1ee3c ki\u1ec3m ch\u1ee9ng:<\/strong> Vi\u1ec7c s\u1eed d\u1ee5ng trong h\u00e0ng th\u1eadp k\u1ef7 qua \u0111\u00e3 l\u00e0m ho\u00e0n thi\u1ec7n c\u00f4ng ngh\u1ec7 NRZ, khi\u1ebfn n\u00f3 tr\u1edf n\u00ean \u0111\u1eb7c bi\u1ec7t b\u1ec1n b\u1ec9 v\u00e0 \u0111\u01b0\u1ee3c hi\u1ec3u r\u00f5 trong nhi\u1ec1u \u1ee9ng d\u1ee5ng ti\u00eau chu\u1ea9n.<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>B\u1ed1i c\u1ea3nh NRZ: C\u00e1c bi\u1ebfn th\u1ec3 v\u00e0 kh\u00e1i ni\u1ec7m then ch\u1ed1t<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">M\u1eb7c d\u00f9 NRZ c\u01a1 b\u1ea3n s\u1eed d\u1ee5ng hai m\u1ee9c, v\u1eabn t\u1ed3n t\u1ea1i c\u00e1c bi\u1ebfn th\u1ec3:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p style=\"margin: 0px;\"><strong>NRZ-L (NRZ-M\u1ee9c):<br><\/strong> Lo\u1ea1i ti\u00eau chu\u1ea9n \u0111\u01b0\u1ee3c m\u00f4 t\u1ea3 \u1edf tr\u00ean, trong \u0111\u00f3 m\u1ee9c \u0111i\u1ec7n \u00e1p tr\u1ef1c ti\u1ebfp bi\u1ec3u th\u1ecb gi\u00e1 tr\u1ecb bit.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>NRZ-I (NRZ-\u0110\u1ea3o):<\/strong> C\u00f2n \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 NRZ vi ph\u00e2n. T\u1ea1i \u0111\u00e2y, m\u1ed9t <em>chuy\u1ec3n \u0111\u1ed5i<\/em> (t\u1eeb cao xu\u1ed1ng th\u1ea5p ho\u1eb7c t\u1eeb th\u1ea5p l\u00ean cao) t\u1ea1i <em>\u0111\u1ea7u<\/em> c\u1ee7a chu k\u1ef3 bit bi\u1ec3u th\u1ecb bit \u20181\u2019, trong khi <em>kh\u00f4ng c\u00f3 chuy\u1ec3n \u0111\u1ed5i<\/em> bi\u1ec3u th\u1ecb bit \u20180\u2019. Ph\u01b0\u01a1ng ph\u00e1p n\u00e0y mang l\u1ea1i kh\u1ea3 n\u0103ng ch\u1ed1ng nhi\u1ec5u t\u1ed1t h\u01a1n \u0111\u1ed1i v\u1edbi m\u1ed9t s\u1ed1 d\u1ea1ng \u0111\u1ea3o pha t\u00edn hi\u1ec7u.<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>\u27a4 Th\u00e1ch th\u1ee9c c\u1ed1t l\u00f5i: Th\u00e0nh ph\u1ea7n DC v\u00e0 hi\u1ec7n t\u01b0\u1ee3ng l\u1ec7ch \u0111\u01b0\u1eddng chu\u1ea9n (Baseline Wander)<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>NRZ<\/strong>\u2018S\u1ef1 \u0111\u01a1n gi\u1ea3n c\u1ee7a.<\/p>\n\n\n\n<ol class=\"wp-block-list\" >\n<li><p style=\"margin: 0px;\"><strong>\u0111i k\u00e8m v\u1edbi nh\u1eefng \u0111\u00e1nh \u0111\u1ed5i v\u1ed1n c\u00f3. Th\u00e1ch th\u1ee9c l\u1edbn nh\u1ea5t b\u1eaft ngu\u1ed3n t\u1eeb vi\u1ec7c thi\u1ebfu c\u00e1c chuy\u1ec3n \u0111\u1ed5i \u0111\u1ea3m b\u1ea3o, \u0111\u1eb7c bi\u1ec7t trong c\u00e1c chu\u1ed7i bit gi\u1ed1ng nhau d\u00e0i (c\u00e1c chu\u1ed7i d\u00e0i g\u1ed3m to\u00e0n \u20181\u2019 ho\u1eb7c to\u00e0n \u20180\u2019).<\/strong> Th\u00e0nh ph\u1ea7n DC:.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>M\u1ed9t chu\u1ed7i d\u00e0i c\u00e1c bit \u20181\u2019 d\u1eabn \u0111\u1ebfn \u0111i\u1ec7n \u00e1p cao k\u00e9o d\u00e0i, th\u1ef1c ch\u1ea5t t\u1ea1o ra m\u1ed9t th\u00e0nh ph\u1ea7n DC (d\u00f2ng \u0111i\u1ec7n m\u1ed9t chi\u1ec1u) trong t\u00edn hi\u1ec7u. Ng\u01b0\u1ee3c l\u1ea1i, m\u1ed9t chu\u1ed7i d\u00e0i c\u00e1c bit \u20180\u2019 t\u1ea1o ra \u0111i\u1ec7n \u00e1p th\u1ea5p k\u00e9o d\u00e0i (c\u00f3 th\u1ec3 l\u00e0 th\u00e0nh ph\u1ea7n DC \u00e2m). Nhi\u1ec1u h\u1ec7 th\u1ed1ng truy\u1ec1n th\u00f4ng, \u0111\u1eb7c bi\u1ec7t l\u00e0 c\u00e1c h\u1ec7 th\u1ed1ng s\u1eed d\u1ee5ng gh\u00e9p n\u1ed1i xoay chi\u1ec1u (AC coupling \u2014 ph\u1ed5 bi\u1ebfn \u1edf \u0111\u1ea7u thu nh\u1eb1m lo\u1ea1i b\u1ecf th\u00e0nh ph\u1ea7n DC), g\u1eb7p kh\u00f3 kh\u0103n khi x\u1eed l\u00fd c\u00e1c th\u00e0nh ph\u1ea7n DC l\u1edbn. \u0110i\u1ec1u n\u00e0y c\u00f3 th\u1ec3 g\u00e2y b\u00e3o h\u00f2a c\u00e1c t\u1ea7ng khu\u1ebfch \u0111\u1ea1i v\u00e0 l\u00e0m m\u00e9o t\u00edn hi\u1ec7u.<\/strong> Hi\u1ec7n t\u01b0\u1ee3ng l\u1ec7ch \u0111\u01b0\u1eddng chu\u1ea9n (Baseline Wander): <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/store-25432-optics-transceivers-sfp-modules.htm\"><strong>b\u1ed9 thu ph\u00e1t quang t\u1ed1c \u0111\u1ed9 cao<\/strong><\/a>.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>Li\u00ean quan \u0111\u1ebfn v\u1ea5n \u0111\u1ec1 th\u00e0nh ph\u1ea7n DC, \u0111\u1ea7u thu s\u1eed d\u1ee5ng m\u1ee9c trung b\u00ecnh c\u1ee7a t\u00edn hi\u1ec7u (\u0111\u01b0\u1eddng chu\u1ea9n) \u0111\u1ec3 ph\u00e2n bi\u1ec7t gi\u1eefa c\u00e1c bit \u20181\u2019 v\u00e0 \u20180\u2019. Trong c\u00e1c chu\u1ed7i d\u00e0i g\u1ed3m c\u00e1c bit gi\u1ed1ng nhau, m\u1ee9c trung b\u00ecnh n\u00e0y c\u00f3 th\u1ec3 d\u1ecbch chuy\u1ec3n (\u201cl\u1ec7ch\u201d) \u0111\u00e1ng k\u1ec3. N\u1ebfu \u0111\u1ed9 l\u1ec7ch qu\u00e1 l\u1edbn, \u0111\u1ea7u thu c\u00f3 th\u1ec3 gi\u1ea3i m\u00e3 sai c\u00e1c bit, d\u1eabn \u0111\u1ebfn l\u1ed7i. Hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y \u0111\u1eb7c bi\u1ec7t nghi\u00eam tr\u1ecdng \u1edf t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u cao tr\u00ean kho\u1ea3ng c\u00e1ch d\u00e0i khi s\u1eed d\u1ee5ng<\/strong> Kh\u00f3 kh\u0103n trong vi\u1ec7c kh\u00f4i ph\u1ee5c \u0111\u1ed3ng h\u1ed3 (Clock Recovery):.<\/p><\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>Vi\u1ec7c \u0111\u1ed3ng b\u1ed9 th\u1eddi gian (\u0111\u1ed3ng h\u1ed3) ch\u00ednh x\u00e1c l\u00e0 \u0111i\u1ec1u thi\u1ebft y\u1ebfu \u0111\u1ec3 l\u1ea5y m\u1eabu t\u00edn hi\u1ec7u \u0111\u00fang th\u1eddi \u0111i\u1ec3m. C\u00e1c m\u1ea1ch kh\u00f4i ph\u1ee5c \u0111\u1ed3ng h\u1ed3 th\u01b0\u1eddng d\u1ef1a v\u00e0o c\u00e1c chuy\u1ec3n \u0111\u1ed5i t\u00edn hi\u1ec7u \u0111\u1ecbnh k\u1ef3 \u0111\u1ec3 \u0111\u1ed3ng b\u1ed9. C\u00e1c chu\u1ed7i d\u00e0i kh\u00f4ng c\u00f3 chuy\u1ec3n \u0111\u1ed5i (chu\u1ed7i d\u00e0i c\u00e1c bit gi\u1ed1ng nhau) khi\u1ebfn \u0111\u1ea7u thu kh\u00f3 duy tr\u00ec s\u1ef1 \u0111\u1ed3ng b\u1ed9 ch\u00ednh x\u00e1c, l\u00e0m t\u0103ng nguy c\u01a1 l\u1ed7i bit.<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u27a4 Gi\u1ea3m thi\u1ec3u c\u00e1c h\u1ea1n ch\u1ebf c\u1ee7a NRZ: X\u00e1o tr\u1ed9n (Scrambling) v\u00e0 m\u00e3 h\u00f3a \u0111\u01b0\u1eddng d\u00e2y (Line Coding)<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p style=\"margin: 0px;\"><strong>C\u00e1c k\u1ef9 s\u01b0 ch\u01b0a t\u1eeb b\u1ecf NRZ v\u00ec nh\u1eefng th\u00e1ch th\u1ee9c n\u00e0y. Nh\u1eefng k\u1ef9 thu\u1eadt th\u00f4ng minh \u0111\u00e3 \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng \u0111\u1ec3 l\u00e0m cho NRZ v\u1eabn kh\u1ea3 thi:<\/strong> X\u00e1o tr\u1ed9n (Scrambling):.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>Tr\u01b0\u1edbc khi m\u00e3 h\u00f3a theo NRZ, lu\u1ed3ng d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c \u0111\u01b0a qua m\u1ed9t b\u1ed9 x\u00e1o tr\u1ed9n. Thi\u1ebft b\u1ecb n\u00e0y l\u00e0m ng\u1eabu nhi\u00ean gi\u1ea3 c\u00e1c chu\u1ed7i bit, ph\u00e1 v\u1ee1 c\u00e1c chu\u1ed7i d\u00e0i c\u00e1c bit gi\u1ed1ng nhau v\u00e0 gi\u1ea3m \u0111\u00e1ng k\u1ec3 th\u00e0nh ph\u1ea7n DC. \u0110\u1ea7u thu s\u1eed d\u1ee5ng m\u1ed9t b\u1ed9 gi\u1ea3i x\u00e1o tr\u1ed9n t\u01b0\u01a1ng \u1ee9ng \u0111\u1ec3 kh\u00f4i ph\u1ee5c d\u1eef li\u1ec7u g\u1ed1c. K\u1ef9 thu\u1eadt x\u00e1o tr\u1ed9n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng r\u1ed9ng r\u00e3i trong c\u00e1c ti\u00eau chu\u1ea9n d\u1ef1a tr\u00ean NRZ (v\u00ed d\u1ee5: Ethernet, Fibre Channel).<\/strong> M\u00e3 h\u00f3a \u0111\u01b0\u1eddng d\u00e2y (v\u00ed d\u1ee5: 8b\/10b): <strong>(1000BASE-SX\/LX)<\/strong> C\u00f3 c\u1ea5u tr\u00fac ch\u1eb7t ch\u1ebd h\u01a1n so v\u1edbi x\u00e1o tr\u1ed9n, m\u00e3 h\u00f3a \u0111\u01b0\u1eddng d\u00e2y thay th\u1ebf t\u1eebng kh\u1ed1i bit d\u1eef li\u1ec7u (v\u00ed d\u1ee5: 8 bit) b\u1eb1ng c\u00e1c t\u1eeb m\u00e3 d\u00e0i h\u01a1n m\u1ed9t ch\u00fat (v\u00ed d\u1ee5: 10 bit). C\u00e1c t\u1eeb m\u00e3 n\u00e0y \u0111\u01b0\u1ee3c ch\u1ecdn \u0111\u1eb7c bi\u1ec7t nh\u1eb1m \u0111\u1ea3m b\u1ea3o \u0111\u1ee7 s\u1ed1 l\u1ea7n chuy\u1ec3n \u0111\u1ed5i (\u0111\u1ec3 kh\u00f4i ph\u1ee5c \u0111\u1ed3ng h\u1ed3) v\u00e0 c\u00e2n b\u1eb1ng th\u00e0nh ph\u1ea7n DC (s\u1ed1 l\u01b0\u1ee3ng bit \u20181\u2019 v\u00e0 \u20180\u2019 b\u1eb1ng nhau theo th\u1eddi gian). M\u1eb7c d\u00f9 k\u1ef9 thu\u1eadt n\u00e0y l\u00e0m t\u0103ng t\u1ea3i (v\u00ed d\u1ee5: 25% cho 8b\/10b), nh\u01b0ng n\u00f3 \u0111\u1ea3m b\u1ea3o c\u00e1c \u0111\u1eb7c t\u00ednh t\u00edn hi\u1ec7u m\u1ed9t c\u00e1ch ch\u1eafc ch\u1eafn. C\u00e1c ti\u00eau chu\u1ea9n nh\u01b0 Gigabit Ethernet.<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>v\u00e0 Fibre Channel ph\u1ee5 thu\u1ed9c m\u1ea1nh v\u00e0o m\u00e3 h\u00f3a 8b\/10b k\u1ebft h\u1ee3p v\u1edbi NRZ.<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u27a4 NRZ so v\u1edbi PAM4: B\u00e0i to\u00e1n b\u0103ng th\u00f4ng <strong>400G, 800G<br><\/strong>, v\u00e0 h\u01a1n th\u1ebf n\u1eefa, nh\u1eefng gi\u1edbi h\u1ea1n c\u01a1 b\u1ea3n c\u1ee7a NRZ tr\u1edf n\u00ean r\u00f5 r\u00e0ng. Vi\u1ec7c t\u0103ng g\u1ea5p \u0111\u00f4i t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u v\u1edbi NRZ v\u1ec1 c\u01a1 b\u1ea3n \u0111\u00f2i h\u1ecfi ph\u1ea3i t\u0103ng g\u1ea5p \u0111\u00f4i b\u0103ng th\u00f4ng t\u00edn hi\u1ec7u. Tuy nhi\u00ean, c\u00e1c th\u00e0nh ph\u1ea7n v\u1eadt l\u00fd \u2014 laser, b\u1ed9 \u0111i\u1ec1u ch\u1ebf, \u0111i-\u1ed1t quang v\u00e0 ch\u00ednh s\u1ee3i quang \u2014 \u0111\u1ec1u c\u00f3 gi\u1edbi h\u1ea1n b\u0103ng th\u00f4ng. \u0110\u00e2y l\u00e0 l\u00fac c\u00e1c s\u01a1 \u0111\u1ed3 \u0111i\u1ec1u ch\u1ebf n\u00e2ng cao nh\u01b0 <strong>PAM4 (\u0110i\u1ec1u ch\u1ebf bi\u00ean \u0111\u1ed9 xung v\u1edbi 4 m\u1ee9c)<\/strong> ph\u00e1t huy vai tr\u00f2.<\/p>\n\n\n\n<figure class=\"wp-block-image aligncenter size-large\"><img decoding=\"async\" width=\"1200\" height=\"712\" src=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/e4a750a380b547c69470323f838f4651.webp\" alt=\"PAM4 vs NRZ\" class=\"wp-image-3822\" srcset=\"https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/e4a750a380b547c69470323f838f4651.webp 1200w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/e4a750a380b547c69470323f838f4651-300x178.webp 300w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/e4a750a380b547c69470323f838f4651-1024x608.webp 1024w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/e4a750a380b547c69470323f838f4651-768x456.webp 768w, https:\/\/resourceslp.szlogic.cn\/wp-content\/uploads\/2026\/05\/e4a750a380b547c69470323f838f4651-18x12.webp 18w\" sizes=\"(max-width: 1200px) 100vw, 1200px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>So s\u00e1nh c\u00e1c s\u01a1 \u0111\u1ed3 \u0111i\u1ec1u ch\u1ebf ch\u00ednh cho <\/strong><a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/store-25432-optics-transceivers-sfp-modules.htm\"><strong>B\u1ed9 thu ph\u00e1t quang<\/strong><\/a><strong>:<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-table\">\n<table class=\"has-fixed-layout\">\n<colgroup><col style=\"min-width: 25px;\"\/><col style=\"min-width: 25px;\"\/><col style=\"min-width: 25px;\"\/><col style=\"min-width: 25px;\"\/><\/colgroup><tbody><tr><th colspan=\"1\" rowspan=\"1\"><p><strong>\u0110\u1eb7c t\u00ednh<\/strong><\/p><\/th><th colspan=\"1\" rowspan=\"1\"><p><strong>NRZ (PAM2)<\/strong><\/p><\/th><th colspan=\"1\" rowspan=\"1\"><p><strong>PAM4<\/strong><\/p><\/th><th colspan=\"1\" rowspan=\"1\"><p><strong>Ghi ch\u00fa<\/strong><\/p><\/th><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>M\u1ee9c<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>2 (Cao, Th\u1ea5p)<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>4 (3 v\u00f9ng m\u1eaft ph\u00e2n bi\u1ec7t)<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>PAM4 n\u00e9n 2 bit tr\u00ean m\u1ed7i k\u00fd hi\u1ec7u<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>Bit tr\u00ean m\u1ed7i k\u00fd hi\u1ec7u<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>1<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>2<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p><strong>\u01afu \u0111i\u1ec3m ch\u00ednh c\u1ee7a PAM4:<\/strong> T\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u cao h\u01a1n v\u1edbi c\u00f9ng t\u1ed1c \u0111\u1ed9 k\u00fd hi\u1ec7u<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>T\u1ed1c \u0111\u1ed9 k\u00fd hi\u1ec7u (Baud)<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>B\u1eb1ng v\u1edbi t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>B\u1eb1ng m\u1ed9t n\u1eeda t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>PAM4 \u0111\u1ea1t t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u g\u1ea5p 2 l\u1ea7n NRZ t\u1ea1i c\u00f9ng t\u1ed1c \u0111\u1ed9 baud, l\u00e0m gi\u1ea3m b\u1edbt \u00e1p l\u1ef1c l\u00ean b\u0103ng th\u00f4ng<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>Nhu c\u1ea7u b\u0103ng th\u00f4ng<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Cao h\u01a1n<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Th\u1ea5p h\u01a1n (cho c\u00f9ng t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u)<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>PAM4 l\u00e0 y\u1ebfu t\u1ed1 then ch\u1ed1t \u0111\u1ec3 \u0111\u1ea1t t\u1ed1c \u0111\u1ed9 400G+ trong gi\u1edbi h\u1ea1n c\u1ee7a c\u00e1c th\u00e0nh ph\u1ea7n<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>\u0110\u1ed9 ph\u1ee9c t\u1ea1p<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Lower<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Cao \u0111\u00e1ng k\u1ec3<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>PAM4 c\u1ea7n x\u1eed l\u00fd t\u00edn hi\u1ec7u s\u1ed1 (DSP) n\u00e2ng cao \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 tuy\u1ebfn t\u00ednh \u1edf \u0111\u1ea7u ph\u00e1t (Tx), \u0111\u1ed9 nh\u1ea1y \u1edf \u0111\u1ea7u thu (Rx) v\u00e0 gi\u1ea3m nhi\u1ec5u<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>Ti\u00eau Th\u1ee5 N\u0103ng L\u01b0\u1ee3ng<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Lower<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Cao h\u01a1n<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>DSP c\u1ee7a PAM4 l\u00e0m t\u0103ng \u0111\u00e1ng k\u1ec3 m\u1ee9c ti\u00eau th\u1ee5 \u0111i\u1ec7n n\u0103ng<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>Cost<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Lower<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>Cao h\u01a1n<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>PAM4 y\u00eau c\u1ea7u c\u00e1c m\u1ea1ch t\u00edch h\u1ee3p (IC) v\u00e0 th\u00e0nh ph\u1ea7n ph\u1ee9c t\u1ea1p h\u01a1n<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>\u0110\u1ed9 to\u00e0n v\u1eb9n t\u00edn hi\u1ec7u<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>\u0110\u00e1ng tin c\u1eady h\u01a1n<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>\u00cdt \u0111\u00e1ng tin c\u1eady h\u01a1n<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>PAM4 c\u00f3 kho\u1ea3ng ch\u00eanh l\u1ec7ch \u0111i\u1ec7n \u00e1p nh\u1ecf h\u01a1n gi\u1eefa c\u00e1c m\u1ee9c, do \u0111\u00f3 nh\u1ea1y c\u1ea3m h\u01a1n v\u1edbi nhi\u1ec5u v\u00e0 suy hao<\/p><\/td><\/tr><tr><td colspan=\"1\" rowspan=\"1\"><p><strong>Tr\u01b0\u1eddng h\u1ee3p s\u1eed d\u1ee5ng \u0111i\u1ec3n h\u00ecnh<\/strong><\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>SR4 1G\/10G\/25G\/100G<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>400G\/800G, &gt;100 m<\/p><\/td><td colspan=\"1\" rowspan=\"1\"><p>NRZ chi\u1ebfm \u01b0u th\u1ebf trong c\u00e1c li\u00ean k\u1ebft chi ph\u00ed nh\u1ea1y c\u1ea3m, t\u1ed1c \u0111\u1ed9\/th\u00f4ng l\u01b0\u1ee3ng th\u1ea5p h\u01a1n; PAM4 d\u00e0nh cho l\u00f5i m\u1ea1ng t\u1ed1c \u0111\u1ed9 cao<\/p><\/td><\/tr><\/tbody>\n<\/table>\n<\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>\u27a4 V\u00ec sao NRZ v\u1eabn t\u1ed3n t\u1ea1i: L\u1eadp lu\u1eadn v\u00ec s\u1ef1 \u0111\u01a1n gi\u1ea3n v\u00e0 chi ph\u00ed<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">D\u00f9 PAM4 \u0111ang n\u1ed5i l\u00ean, NRZ v\u1eabn ch\u01b0a l\u1ed7i th\u1eddi. Nh\u1eefng \u01b0u \u0111i\u1ec3m c\u1ee7a n\u00f3 t\u1ecfa s\u00e1ng trong c\u00e1c t\u00ecnh hu\u1ed1ng c\u1ee5 th\u1ec3:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p style=\"margin: 0px;\"><strong>C\u00e1c \u1ee9ng d\u1ee5ng nh\u1ea1y c\u1ea3m v\u1ec1 chi ph\u00ed:<\/strong> \u0110\u1ed1i v\u1edbi c\u00e1c li\u00ean k\u1ebft 10G, 25G v\u00e0 th\u1eadm ch\u00ed nhi\u1ec1u li\u00ean k\u1ebft 100G (\u0111\u1eb7c bi\u1ec7t l\u00e0 c\u00e1c kho\u1ea3ng c\u00e1ch ng\u1eafn nh\u01b0 <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/473115.htm\"><strong>100G-SR4<\/strong><\/a> s\u1eed d\u1ee5ng quang h\u1ecdc song song), c\u00e1c gi\u1ea3i ph\u00e1p d\u1ef1a tr\u00ean NRZ <strong>b\u1ed9 thu ph\u00e1t quang<\/strong> mang l\u1ea1i gi\u1ea3i ph\u00e1p kinh t\u1ebf nh\u1ea5t. Thi\u1ebft k\u1ebf \u0111\u01a1n gi\u1ea3n h\u01a1n tr\u1ef1c ti\u1ebfp chuy\u1ec3n h\u00f3a th\u00e0nh chi ph\u00ed module th\u1ea5p h\u01a1n.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>M\u1ee9c ti\u00eau th\u1ee5 \u0111i\u1ec7n n\u0103ng th\u1ea5p h\u01a1n:<\/strong> Kh\u00f4ng c\u1ea7n b\u1ed9 x\u1eed l\u00fd t\u00edn hi\u1ec7u s\u1ed1 (DSP) ph\u1ee9c t\u1ea1p <a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/vi\/glossary\/digital-signal-processor-functionality-in-optical-transceivers\/\"><strong>ti\u00ean ti\u1ebfn<\/strong><\/a> m\u00e0 PAM4 y\u00eau c\u1ea7u, c\u00e1c module NRZ <strong>module quang<br><\/strong> th\u01b0\u1eddng ti\u00eau th\u1ee5 \u00edt \u0111i\u1ec7n n\u0103ng h\u01a1n \u2014 m\u1ed9t y\u1ebfu t\u1ed1 then ch\u1ed1t trong c\u00e1c m\u00f4i tr\u01b0\u1eddng trung t\u00e2m d\u1eef li\u1ec7u m\u1eadt \u0111\u1ed9 cao v\u00e0 c\u00e1c v\u1ecb tr\u00ed bi\u00ean b\u1ecb gi\u1edbi h\u1ea1n v\u1ec1 \u0111i\u1ec7n n\u0103ng.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>Hi\u1ec7u n\u0103ng \u0111\u1ee7 d\u00f9ng:<\/strong> \u0110\u1ed1i v\u1edbi m\u1ea1ng doanh nghi\u1ec7p, c\u00e1c k\u1ebft n\u1ed1i n\u1ed9i b\u1ed9 trung t\u00e2m d\u1eef li\u1ec7u trong c\u00f9ng m\u1ed9t gi\u00e1 \u0111\u1ee1 ho\u1eb7c h\u00e0ng, v\u00e0 nhi\u1ec1u \u1ee9ng d\u1ee5ng truy c\u1eadp vi\u1ec5n th\u00f4ng, NRZ cung c\u1ea5p hi\u1ec7u n\u0103ng v\u00e0 ph\u1ea1m vi \u0111\u1ee7 d\u00f9ng m\u00e0 kh\u00f4ng c\u1ea7n g\u00e1nh n\u1eb7ng ph\u1ee9c t\u1ea1p.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>H\u1ec7 sinh th\u00e1i tr\u01b0\u1edfng th\u00e0nh:<\/strong> C\u01a1 s\u1edf h\u1ea1 t\u1ea7ng \u0111\u00e3 tri\u1ec3n khai quy m\u00f4 l\u1edbn, quy tr\u00ecnh s\u1ea3n xu\u1ea5t \u0111\u00e3 \u0111\u01b0\u1ee3c ki\u1ec3m ch\u1ee9ng v\u00e0 ki\u1ebfn th\u1ee9c k\u1ef9 thu\u1eadt s\u00e2u r\u1ed9ng v\u1ec1 NRZ \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 tin c\u1eady v\u00e0 kh\u1ea3 n\u0103ng t\u00edch h\u1ee3p d\u1ec5 d\u00e0ng.<\/p><\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>\u27a4 B\u1ed9 thu ph\u00e1t quang LINK-PP: Cung c\u1ea5p k\u1ebft n\u1ed1i NRZ \u0111\u00e1ng tin c\u1eady<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">T\u1ea1i LINK-PP, ch\u00fang t\u00f4i th\u1ea5u hi\u1ec3u gi\u00e1 tr\u1ecb b\u1ec1n v\u1eefng c\u1ee7a c\u00f4ng ngh\u1ec7 NRZ. Danh m\u1ee5c s\u1ea3n ph\u1ea9m to\u00e0n di\u1ec7n g\u1ed3m c\u00e1c module thu ph\u00e1t quang ch\u1ea5t l\u01b0\u1ee3ng cao, tu\u00e2n th\u1ee7 chu\u1ea9n <strong>b\u1ed9 thu ph\u00e1t quang<\/strong> c\u1ee7a ch\u00fang t\u00f4i t\u1eadn d\u1ee5ng s\u01a1 \u0111\u1ed3 \u0111i\u1ec1u ch\u1ebf NRZ nh\u1eb1m mang l\u1ea1i hi\u1ec7u n\u0103ng \u0111\u00e1ng tin c\u1eady v\u00e0 chi ph\u00ed hi\u1ec7u qu\u1ea3 cho v\u00f4 s\u1ed1 \u1ee9ng d\u1ee5ng:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><p style=\"margin: 0px;\"><strong>Gi\u1ea3i ph\u00e1p 10G:<\/strong> C\u00e1c <strong>SFP-10G-LR<\/strong> <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/475586.htm\"><strong>LS-SM3110-10C<\/strong><\/a> and <strong>SFP-10G-SR<br><\/strong> <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/475415.htm\"><strong>LS-MM8510-S3C<\/strong><\/a> cung c\u1ea5p k\u1ebft n\u1ed1i m\u1ea1nh m\u1ebd, ti\u00eau th\u1ee5 \u0111i\u1ec7n n\u0103ng th\u1ea5p cho nhu c\u1ea7u Ethernet 10 Gigabit truy\u1ec1n th\u1ed1ng tr\u00ean <strong>s\u1ee3i quang \u0111\u01a1n mode v\u00e0 \u0111a mode<\/strong>, t\u01b0\u01a1ng \u1ee9ng.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>Hi\u1ec7u qu\u1ea3 25G:<\/strong> \u0110\u1ed1i v\u1edbi vi\u1ec7c truy c\u1eadp m\u00e1y ch\u1ee7 th\u1ebf h\u1ec7 m\u1edbi v\u00e0 kh\u00f4ng d\u00e2y <a target=\"_blank\" rel=\"\" href=\"https:\/\/resourceslp.szlogic.cn\/vi\/knowledge-center\/5g-fronthaul-high-speed-low-latency-communication-explained\/\"><strong>fronthaul<\/strong><\/a>, c\u00e1c module <strong>SFP28-LR<\/strong> <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/476046.htm\"><strong>LS-SM3125-10C<br><\/strong><\/a> and <strong>SFP28-SR<\/strong> <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/473141.htm\"><strong>LS-MM8525-S1C<\/strong><\/a> c\u1ee7a ch\u00fang t\u00f4i mang \u0111\u1ebfn s\u1ef1 k\u1ebft h\u1ee3p ho\u00e0n h\u1ea3o gi\u1eefa t\u00ednh \u0111\u01a1n gi\u1ea3n c\u1ee7a NRZ v\u00e0 hi\u1ec7u n\u0103ng 25G.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>T\u1eadp h\u1ee3p 100G:<\/strong> T\u1eadn d\u1ee5ng c\u00e1c k\u00eanh NRZ song song, c\u00e1c module nh\u01b0 <strong>QSFP28-100G-SR4<br><\/strong> <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/products\/473115.htm\"><strong>LQ-M85100-SR4C<\/strong><\/a> c\u1ee7a ch\u00fang t\u00f4i cung c\u1ea5p k\u1ebft n\u1ed1i 100G m\u1eadt \u0111\u1ed9 cao trong trung t\u00e2m d\u1eef li\u1ec7u b\u1eb1ng s\u1ee3i quang \u0111a mode \u2014 gi\u1ea3i ph\u00e1p ch\u1ee7 l\u1ef1c cho vi\u1ec7c t\u1eadp h\u1ee3p chi ph\u00ed hi\u1ec7u qu\u1ea3.<\/p><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Ch\u00fang t\u00f4i ki\u1ec3m tra nghi\u00eam ng\u1eb7t t\u1ea5t c\u1ea3 c\u00e1c <a target=\"_blank\" rel=\"\" href=\"https:\/\/www.l-p.com\/store-25432-optics-transceivers-sfp-modules.htm\"><strong>module thu ph\u00e1t quang LINK-PP<\/strong><\/a>, bao g\u1ed3m c\u1ea3 d\u00f2ng s\u1ea3n ph\u1ea9m NRZ, v\u1ec1 kh\u1ea3 n\u0103ng t\u01b0\u01a1ng t\u00e1c, hi\u1ec7u n\u0103ng v\u00e0 tu\u1ed5i th\u1ecd, \u0111\u1ea3m b\u1ea3o t\u00edch h\u1ee3p li\u1ec1n m\u1ea1ch v\u00e0o c\u01a1 s\u1edf h\u1ea1 t\u1ea7ng m\u1ea1ng c\u1ee7a b\u1ea1n.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>\u27a4 T\u01b0\u01a1ng lai: V\u1ecb tr\u00ed \u0111\u1eb7c th\u00f9 c\u1ee7a NRZ trong th\u1ebf gi\u1edbi PAM4<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Xu h\u01b0\u1edbng r\u00f5 r\u00e0ng: PAM4 l\u00e0 y\u1ebfu t\u1ed1 thi\u1ebft y\u1ebfu \u0111\u1ec3 \u0111\u1ea9y t\u1ed1c \u0111\u1ed9 d\u1eef li\u1ec7u v\u01b0\u1ee3t qu\u00e1 100G tr\u00ean m\u1ed7i b\u01b0\u1edbc s\u00f3ng trong kho\u1ea3ng c\u00e1ch ti\u00eau chu\u1ea9n. Tuy nhi\u00ean, \u0111i\u1ec1u ch\u1ebf NRZ s\u1ebd ti\u1ebfp t\u1ee5c \u0111\u00f3ng vai tr\u00f2 then ch\u1ed1t:<\/p>\n\n\n\n<ol class=\"wp-block-list\" >\n<li><p style=\"margin: 0px;\"><strong>H\u1ed7 tr\u1ee3 h\u1ec7 th\u1ed1ng c\u0169:<\/strong> H\u00e0ng t\u1ef7 c\u1ed5ng d\u1ef1a tr\u00ean NRZ s\u1ebd v\u1eabn ho\u1ea1t \u0111\u1ed9ng trong nhi\u1ec1u n\u0103m t\u1edbi.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>C\u00e1c ph\u00e2n kh\u00fac t\u1ed1i \u01b0u chi ph\u00ed:<\/strong> \u0110\u1ed1i v\u1edbi c\u00e1c m\u1ee9c t\u1ed1c \u0111\u1ed9 m\u00e0 NRZ \u0111\u00e1p \u1ee9ng \u0111\u1ee7 (10G, 25G, m\u1ed9t s\u1ed1 \u1ee9ng d\u1ee5ng 100G c\u1ee5 th\u1ec3), n\u00f3 s\u1ebd ti\u1ebfp t\u1ee5c l\u00e0 l\u1ef1a ch\u1ecdn kinh t\u1ebf nh\u1ea5t cho <strong>b\u1ed9 thu ph\u00e1t quang<\/strong> tri\u1ec3n khai.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>C\u00e1c \u1ee9ng d\u1ee5ng chuy\u00ean bi\u1ec7t:<\/strong> C\u00e1c k\u1ebft n\u1ed1i kho\u1ea3ng c\u00e1ch r\u1ea5t ng\u1eafn t\u1eeb chip \u0111\u1ebfn chip ho\u1eb7c bo m\u1ea1ch \u0111\u1ebfn bo m\u1ea1ch c\u00f3 th\u1ec3 \u01b0u ti\u00ean t\u00ednh \u0111\u01a1n gi\u1ea3n c\u1ee7a NRZ.<\/p><\/li><li><p style=\"margin: 0px;\"><strong>Quang h\u1ecdc song song:<\/strong> \u0110\u1ea1t t\u1ed1c \u0111\u1ed9 t\u1ed5ng h\u1ee3p cao (v\u00ed d\u1ee5 400G) b\u1eb1ng c\u00e1ch s\u1eed d\u1ee5ng nhi\u1ec1u k\u00eanh NRZ song song (v\u00ed d\u1ee5 8\u00d750G NRZ trong QSFP-DD) v\u1eabn l\u00e0 m\u1ed9t gi\u1ea3i ph\u00e1p c\u1ea1nh tranh, th\u01b0\u1eddng c\u00e2n b\u1eb1ng hi\u1ec7u qu\u1ea3 gi\u1eefa chi ph\u00ed v\u00e0 \u0111i\u1ec7n n\u0103ng so v\u1edbi 2\u00d7200G PAM4.<\/p><\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\" ><strong>\u27a4 K\u1ebft lu\u1eadn<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Kh\u00f4ng quay v\u1ec1-zero (NRZ)<\/strong> Vi\u1ec7c m\u00e3 h\u00f3a l\u00e0 minh ch\u1ee9ng cho s\u1ee9c m\u1ea1nh c\u1ee7a s\u1ef1 \u0111\u01a1n gi\u1ea3n tinh t\u1ebf trong k\u1ef9 thu\u1eadt. D\u00f9 g\u1eb7p gi\u1edbi h\u1ea1n b\u0103ng th\u00f4ng \u0111\u1ed1i v\u1edbi t\u1ed1c \u0111\u1ed9 \u0111\u01a1n k\u00eanh \u1edf m\u1ee9c ti\u00ean ti\u1ebfn nh\u1ea5t, nh\u01b0ng nh\u1eefng \u01b0u \u0111i\u1ec3m v\u1ed1n c\u00f3 c\u1ee7a NRZ v\u1ec1 chi ph\u00ed, \u0111i\u1ec7n n\u0103ng v\u00e0 \u0111\u1ed9 tin c\u1eady \u0111\u1ea3m b\u1ea3o v\u1ecb th\u1ebf ti\u1ebfp t\u1ee5c t\u1ed3n t\u1ea1i c\u1ee7a n\u00f3 tr\u00ean m\u1ed9t ph\u1ea7n l\u1edbn c\u1ea3nh quan m\u1ea1ng. Vi\u1ec7c hi\u1ec3u r\u00f5 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a NRZ, c\u00e1c th\u00e1ch th\u1ee9c c\u1ee7a n\u00f3 nh\u01b0 hi\u1ec7n t\u01b0\u1ee3ng tr\u00f4i n\u1ec1n (baseline wander) \u0111\u01b0\u1ee3c kh\u1eafc ph\u1ee5c nh\u1edd khu\u1ebfch t\u00e1n (scrambling) v\u00e0 m\u00e3 h\u00f3a, c\u0169ng nh\u01b0 v\u1ecb tr\u00ed c\u1ee7a n\u00f3 so v\u1edbi PAM4, l\u00e0 n\u1ec1n t\u1ea3ng thi\u1ebft y\u1ebfu \u0111\u1ec3 ra quy\u1ebft \u0111\u1ecbnh s\u00e1ng su\u1ed1t v\u1ec1 <strong>b\u1ed9 thu ph\u00e1t quang<\/strong> c\u00f4ng ngh\u1ec7.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>S\u1eb5n s\u00e0ng kh\u00e1m ph\u00e1 gi\u1ea3i ph\u00e1p k\u1ebft n\u1ed1i quang t\u1ed1i \u01b0u cho nhu c\u1ea7u c\u1ee7a b\u1ea1n?<\/strong> D\u00f9 b\u1ea1n c\u1ea7n hi\u1ec7u qu\u1ea3 chi ph\u00ed \u0111\u00e3 \u0111\u01b0\u1ee3c ki\u1ec3m ch\u1ee9ng c\u1ee7a c\u00e1c module <strong>transceiver quang h\u1ecdc LINK-PP<\/strong> d\u1ef1a tr\u00ean NRZ nh\u01b0 <strong>SFP-10G-LR<\/strong> or <strong>QSFP28-100G-SR4<br><\/strong>, c\u1ee7a ch\u00fang t\u00f4i, hay \u0111ang h\u01b0\u1edbng t\u1edbi c\u00e1c gi\u1ea3i ph\u00e1p PAM4 t\u1ed1c \u0111\u1ed9 cao h\u01a1n, LINK-PP cung c\u1ea5p danh m\u1ee5c s\u1ea3n ph\u1ea9m to\u00e0n di\u1ec7n g\u1ed3m c\u00e1c module hi\u1ec7u n\u0103ng cao, \u0111\u00e1ng tin c\u1eady. <\/p>\n\n\n\n<div><div widgetid=\"3ef779ac451211f099380a58fbc66727\" format=\"embedded\" data-widget-id=\"3ef779ac451211f099380a58fbc66727\" data-mode=\"production.zh\" style=\"display: block;\"><\/div><\/div>\n\n\n\n<script src=\"https:\/\/cdn.mylandingpages.co\/widgets\/platform\/platform.widget.js\" async=\"true\"><\/script>","protected":false},"excerpt":{"rendered":"<p>Ph\u01b0\u01a1ng ph\u00e1p m\u00e3 h\u00f3a Kh\u00f4ng quay v\u1ec1-zero (NRZ) l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p m\u00e3 h\u00f3a k\u1ef9 thu\u1eadt s\u1ed1 s\u1eed d\u1ee5ng hai m\u1ee9c \u0111i\u1ec7n \u00e1p \u0111\u1ec3 bi\u1ec3u di\u1ec5n d\u1eef li\u1ec7u nh\u1ecb ph\u00e2n, mang l\u1ea1i t\u00ednh \u0111\u01a1n gi\u1ea3n v\u00e0 hi\u1ec7u qu\u1ea3 trong truy\u1ec1n th\u00f4ng k\u1ef9 thu\u1eadt s\u1ed1.<\/p>","protected":false},"author":1,"featured_media":3819,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[27],"tags":[26],"class_list":["post-3823","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-glossary","tag-optics-transceivers"],"blocksy_meta":[],"acf":[],"_links":{"self":[{"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/posts\/3823","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/comments?post=3823"}],"version-history":[{"count":4,"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/posts\/3823\/revisions"}],"predecessor-version":[{"id":11371,"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/posts\/3823\/revisions\/11371"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/media\/3819"}],"wp:attachment":[{"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/media?parent=3823"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/categories?post=3823"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/resourceslp.szlogic.cn\/vi\/wp-json\/wp\/v2\/tags?post=3823"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}