{"id":10374,"date":"2021-11-21T19:55:31","date_gmt":"2021-11-21T12:55:31","guid":{"rendered":"https:\/\/www.vietlearn.org\/post\/?p=10374"},"modified":"2021-11-21T20:11:19","modified_gmt":"2021-11-21T13:11:19","slug":"tin-hieu-tuong-tu-tin-hieu-so","status":"publish","type":"post","link":"https:\/\/www.vietlearn.org\/kien-thuc\/tin-hieu-tuong-tu-tin-hieu-so\/","title":{"rendered":"T\u00edn hi\u1ec7u t\u01b0\u01a1ng t\u1ef1; T\u00edn hi\u1ec7u s\u1ed1."},"content":{"rendered":"\n

Nh\u1eefng ph\u01b0\u01a1ng ti\u1ec7n th\u00f4ng tin v\u00f4 tuy\u1ebfn nh\u01b0 \u0111i\u1ec7n tho\u1ea1i kh\u00f4ng d\u00e2y, m\u00e1y nh\u1eafn tin v\u00e0 \u0111i\u1ec7n tho\u1ea1i \u0111\u01a1n c\u00f4ng v\u00f4 tuy\u1ebfn (h\u1ec7 th\u1ed1ng truy\u1ec1n th\u00f4ng n\u1ed9i b\u1ed9 – inter communication system) \u0111\u1ec1u s\u1eed d\u1ee5ng trong khi di chuy\u1ec3n. Lo\u1ea1i ph\u01b0\u01a1ng th\u1ee9c truy\u1ec1n th\u00f4ng n\u00e0y g\u1ecdi chung l\u00e0 th\u00f4ng tin di \u0111\u1ed9ng (truy\u1ec1n th\u00f4ng di \u0111\u1ed9ng).<\/p>\n\n\n\n

Th\u00f4ng tin di \u0111\u1ed9ng truy\u1ec1n t\u1ea3i th\u00f4ng tin nh\u1edd v\u00e0o s\u00f3ng \u0111i\u1ec7n t\u1eeb. V\u00f9ng s\u00f3ng \u0111i\u1ec7n t\u1eeb truy\u1ec1n \u0111\u1ebfn g\u1ecdi l\u00e0 v\u00f9ng ph\u1ee7 s\u00f3ng v\u00f4 tuy\u1ebfn. Ng\u01b0\u1eddi ta tay c\u1ea7m \u0111i\u1ec7n tho\u1ea1i di \u0111\u1ed9ng ho\u1eb7c nh\u1eefng ph\u01b0\u01a1ng ti\u1ec7n th\u00f4ng tin di \u0111\u1ed9ng kh\u00e1c, ch\u1ec9 c\u1ea7n \u1edf trong v\u00f9ng ph\u1ee7 s\u00f3ng v\u00f4 tuy\u1ebfn c\u1ee7a th\u00f4ng tin di \u0111\u1ed9ng th\u1ed1ng nh\u1ea5t v\u1edbi \u0111\u1ecba b\u00e0n c\u1ee7a m\u1ed9t th\u00e0nh ph\u1ed1. Mu\u1ed1n ph\u1ee7 s\u00f3ng l\u00ean m\u1ed9t di\u1ec7n t\u00edch r\u1ed9ng nh\u01b0 v\u1eady, th\u00ec ph\u1ea3i d\u00f9ng v\u00f9ng ph\u1ee7 c\u00f3 h\u00ecnh d\u00e1ng th\u1ebf n\u00e0o cho hay \u0111\u00e2y?<\/p>\n\n\n\n

S\u00f3ng v\u00f4 tuy\u1ebfn ph\u00e1t t\u00edn hi\u1ec7u ra t\u1ee9 ph\u00eda qua anten \u0111\u00e0i m\u1eb7t \u0111\u1ea5t. Khu v\u1ef1c ph\u1ee7 s\u00f3ng l\u00e0 m\u1ed9t h\u00ecnh tr\u00f2n. Nh\u1eefng n\u0103m g\u1ea7n \u0111\u00e2y ng\u01b0\u1eddi s\u1eed d\u1ee5ng \u0111i\u1ec7n tho\u1ea1i di \u0111\u1ed9ng t\u0103ng l\u00ean r\u1ea5t nhi\u1ec1u, m\u00e0 t\u00e0i nguy\u00ean t\u1ea7n s\u1ed1 th\u00ec c\u00f3 h\u1ea1n. \u0110\u1ec3 l\u1ee3i d\u1ee5ng tri\u1ec7t \u0111\u1ec3 t\u1ea7n s\u1ed1 v\u00f4 tuy\u1ebfn, gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1 “m\u1eadt \u00edt ru\u1ed3i nhi\u1ec1u”, c\u00e1c chuy\u00ean gia<\/a> th\u00f4ng tin ph\u00f2ng th\u1ef1c nghi\u1ec7m Bell (Bell laboratories) c\u1ee7a M\u0129 \u0111\u1ec1 xu\u1ea5t \u00fd ki\u1ebfn thi\u1ebft l\u1eadp h\u1ec7 th\u1ed1ng \u0111i\u1ec7n tho\u1ea1i di \u0111\u1ed9ng ki\u1ec3u t\u1ed5 ong. T\u1ea1i sao l\u1ea1i chia ti\u1ec3u khu v\u00f4 tuy\u1ebfn th\u00e0nh d\u1ea1ng t\u1ed5 ong.<\/p>\n\n\n\n

Trong t\u1ef1 nhi\u00ean ng\u01b0\u1eddi ta ph\u00e1t hi\u1ec7n ra m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng k\u1ef3 l\u1ea1: t\u1ed5 con ong m\u1eadt \u0111\u01b0\u1ee3c b\u1ed1 tr\u00ed x\u1eafp x\u1ebfp theo c\u00e1ch x\u1ebfp li\u1ec1n c\u00e1c bu\u1ed3ng nh\u1ecf c\u00f3 h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u. Lo\u1ea1i c\u1ea5u tr\u00fac n\u00e0y c\u1ee7a t\u1ed5 ong \u0111\u00e3 thu h\u00fat s\u1ef1 ch\u00fa \u00fd c\u1ee7a c\u00e1c nh\u00e0 khoa h\u1ecdc. Ph\u00e2n t\u00edch k\u0129 th\u00ec h\u00ecnh l\u1ee5c l\u0103ng chi\u1ebfm kh\u00f4ng gian l\u1edbn nh\u1ea5t, s\u1eed d\u1ee5ng v\u1eadt li\u1ec7u l\u00e0 h\u1ee3p l\u00ed.<\/p>\n\n\n\n

V\u00e0 th\u1ebf l\u00e0 ng\u01b0\u1eddi ta \u0111\u00e3 \u1ee9ng d\u1ee5ng c\u1ea5u tr\u00fac n\u00e0y v\u00e0o khu v\u1ef1c ph\u1ee7 s\u00f3ng v\u00f4 tuy\u1ebfn. \u0110\u00e0i c\u0103n c\u1ee9 \u0111i\u1ec7n tho\u1ea1i v\u00f4 tuy\u1ebfn s\u1eed d\u1ee5ng anten to\u00e0n h\u01b0\u1edbng, h\u00ecnh d\u1ea1ng ph\u1ee7 \u0111\u1ea1i th\u1ec3 l\u00e0 m\u1ed9t h\u00ecnh tr\u00f2n. Nh\u01b0ng do c\u00e1c ti\u1ec3u khu x\u1ebfp gi\u00e1p nhau, d\u00f9ng ti\u1ec3u khu h\u00ecnh tr\u00f2n m\u00e0 x\u1ebfp l\u1ea1i th\u00ec t\u1ea5t nhi\u00ean l\u00e0 s\u1ebd n\u1ea3y sinh ra nh\u1eefng kho\u1ea3ng tr\u1ed1ng l\u1edbn ho\u1eb7c b\u1ecb ch\u1ed3ng l\u1ea5p. N\u1ebfu l\u1ea7n l\u01b0\u1ee3t x\u1ebfp c\u00e1c lo\u1ea1i h\u00ecnh vu\u00f4ng, h\u00ecnh thoi, h\u00ecnh tam gi\u00e1c \u0111\u1ec1u, h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u v.v. l\u1edbn \u0111\u1ec1u b\u1eb1ng nhau, ta s\u1ebd ph\u00e1t hi\u1ec7n ra ch\u1ec9 c\u00f3 h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u, h\u00ecnh tam gi\u00e1c \u0111\u1ec1u v\u00e0 h\u00ecnh vu\u00f4ng m\u1edbi kh\u00f4ng sinh ra khe h\u1edf v\u00e0 ch\u1ed3ng l\u1ea5n. Tr\u00ean th\u1ef1c t\u1ebf th\u00ec m\u1ed7i ti\u1ec3u khu c\u00f3 v\u00f9ng ph\u1ee7 h\u1eefu hi\u1ec7u l\u00e0 m\u1ed9t h\u00ecnh \u0111a gi\u00e1c n\u1ed9i ti\u1ebfp h\u00ecnh tr\u00f2n. N\u1ebfu ti\u1ec3u khu ch\u1ecdn h\u00ecnh tam gi\u00e1c \u0111\u1ec1u th\u00ec ph\u1ea7n ch\u1ed3ng l\u1ea5n gi\u1eefa hai v\u00f9ng li\u1ec1n k\u1ec1 qu\u00e1 l\u1edbn, h\u00ecnh vu\u00f4ng c\u00f3 kh\u00e1 h\u01a1n. Ch\u1ed3ng l\u1ea5n \u00edt nh\u1ea5t v\u1eabn l\u00e0 h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u.<\/p>\n\n\n\n

B\u1edfi v\u1eady, ch\u1ecdn d\u00f9ng h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u c\u00f3 th\u1ec3 l\u00e0m cho di\u1ec7n t\u00edch h\u1eefu hi\u1ec7u ti\u1ec3u khu ph\u1ee7 s\u00f3ng v\u00f4 tuy\u1ebfn l\u1edbn nh\u1ea5t. Ph\u1ee7 s\u00f3ng l\u00ean v\u00f9ng ph\u1ee5c v\u1ee5 v\u1edbi di\u1ec7n t\u00edch nh\u01b0 v\u1eady th\u00ec c\u1ea7n h\u00e0ng \u0111\u01a1n v\u1ecb ti\u1ec3u khu l\u00e0 nh\u1ecf nh\u1ea5t. Nh\u01b0 v\u1eady c\u00f3 th\u1ec3 ti\u1ebft ki\u1ec7m \u0111\u1ea7u t\u01b0 x\u00e2y d\u1ef1ng. V\u00e0 ch\u1ec9 c\u1ea7n \u0111i\u1ec1u khi\u1ec3n v\u1ec1 c\u01b0\u1eddng \u0111\u1ed9 s\u00f3ng v\u00f4 tuy\u1ebfn ph\u00e1t ra, cho n\u00f3 h\u1ea1n ch\u1ebf trong ph\u1ea1m vi ti\u1ec3u khu l\u00e0 \u0111\u01b0\u1ee3c. \u0110\u1ed3ng th\u1eddi, trong ti\u1ec3u khu l\u00e2n c\u1eadn, ch\u1ecdn d\u00f9ng t\u1ea7n s\u1ed1 kh\u00e1c nhau \u0111\u1ec3 \u0111\u00e0m tho\u1ea1i th\u00ec c\u00f3 th\u1ec3 tr\u00e1nh \u0111\u01b0\u1ee3c nhi\u1ec5u. Nh\u01b0 v\u1eady, trong ti\u1ec3u khu kho\u1ea3ng c\u00e1ch nh\u1ea5t \u0111\u1ecbnh c\u00f3 th\u1ec3 d\u00f9ng t\u1ea7n s\u1ed1 nh\u01b0 nhau. T\u1ea7n s\u1ed1 c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng tr\u00f9ng l\u1eb7p, t\u1eeb \u0111\u00f3 \u0111\u00e3 gi\u1ea3i quy\u1ebft v\u1ea5n \u0111\u1ec1 t\u00e0i nguy\u00ean t\u1ea7n s\u1ed1 kh\u00f4ng \u0111\u1ee7. B\u1edfi v\u1eady, trong th\u00f4ng tin di \u0111\u1ed9ng, \u00e1p d\u1ee5ng ti\u1ec3u khu v\u00f4 tuy\u1ebfn h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u \u0111\u1ec3 ti\u1ebfp n\u1ed1i ph\u1ee7 s\u00f3ng l\u00ean to\u00e0n b\u1ed9 v\u00f9ng d\u1ecbch v\u1ee5 l\u00e0 ph\u01b0\u01a1ng \u00e1n t\u1ed1i \u01b0u.<\/p>\n\n\n\n

H\u00ecnh d\u1ea1ng v\u00f9ng ph\u1ee7 s\u00f3ng v\u00f4 tuy\u1ebfn h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u t\u1ef1a nh\u01b0 t\u1ed5 ong. Ti\u1ec3u khu v\u00f4 tuy\u1ebfn ki\u1ec3u t\u1ed5 ong v\u00e0 m\u1ea1ng \u0111i\u1ec7n tho\u1ea1i di \u0111\u1ed9ng ki\u1ec3u t\u1ed5 ong do v\u1eady m\u00e0 c\u00f3 t\u00ean.<\/p>\n\n\n\n

T\u1eeb kh\u00f3a: Th\u00f4ng tin di \u0111\u1ed9ng (truy\u1ec1n th\u00f4ng di \u0111\u1ed9ng); V\u00f9ng ph\u1ee7 s\u00f3ng v\u00f4 tuy\u1ebfn \u0111i\u1ec7n; Ti\u1ec3u<\/p>\n","protected":false},"excerpt":{"rendered":"

Nh\u1eefng ph\u01b0\u01a1ng ti\u1ec7n th\u00f4ng tin v\u00f4 tuy\u1ebfn nh\u01b0 \u0111i\u1ec7n tho\u1ea1i kh\u00f4ng d\u00e2y, m\u00e1y nh\u1eafn tin v\u00e0 \u0111i\u1ec7n tho\u1ea1i \u0111\u01a1n c\u00f4ng v\u00f4 tuy\u1ebfn (h\u1ec7 th\u1ed1ng truy\u1ec1n th\u00f4ng n\u1ed9i b\u1ed9 – inter communication system) \u0111\u1ec1u s\u1eed d\u1ee5ng trong khi di chuy\u1ec3n. Lo\u1ea1i ph\u01b0\u01a1ng th\u1ee9c truy\u1ec1n th\u00f4ng n\u00e0y g\u1ecdi chung l\u00e0 th\u00f4ng tin di \u0111\u1ed9ng (truy\u1ec1n th\u00f4ng di […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_disable_autopaging":false},"categories":[15,13],"tags":[],"class_list":["post-10374","post","type-post","status-publish","format-standard","hentry","category-hoi-dap-khoa-hoc","category-tin-hoc"],"_links":{"self":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10374","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/comments?post=10374"}],"version-history":[{"count":0,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/posts\/10374\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/media?parent=10374"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/categories?post=10374"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.vietlearn.org\/kien-thuc\/wp-json\/wp\/v2\/tags?post=10374"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}