Nyquist theorem - isiseko theoretical component kubuchwepheshe ulwazi lwangoku

Zimbalwa impumelelo nempembelelo ngoko ngamandla kuphuhliso yonxibelelwano kunye nolwazi ubugcisa, njengoko Nyquist theorem. Ubukhulu becala, le Scientist ekuhombisile ilizwe lethu kungekho ngaphantsi kwe-SP Queens, okanye AS Popov. Kusenokwenzeka ukuba Kotelnikov eyaziwa ngaphandle eRashiya ngaphezu kwi Lezwe nokuba.

Le udumo na ingcaciso yayo. Nyquist theorem waba sisiseko theoretical kuzo zonke izixhobo zale mihla digital ezisetyenziswa kunxibelelwano. Oku kusekelwe kumgaqo idijithali naluphi uphawu okanye umfanekiso. Oku kudala iimeko ukuze kubalwe yonxibelelwano multi-umsele ababini umqondiso. Ngenxa Nyquist theorem, unako ukubuyisela nengxolo kunye uphawu 'idlakadlaka ", ukudala omzimba ka. ubuchule incazelo kwakhona isekelwe kule theorem. Mhlawumbi yena uyakwazi ukufumana ezinye izicelo luncedo.

Umbhali ezibalulekileyo ezifana kuphuhliso kanomathotholo theory wazalwa ngo-1908 Kazan. Uyise waba uprofesa waseyunivesithi, injineli odumileyo kunye yezibalo uAleksandr Petrovich Kotelnikov, ngoko xa kufikwa yemfuza, inzululwazi e Victor Alexandrovich yaba 'egazini ". Emva kokuphumelela Moscow Energy Institute, lo mfana waya ugqibe esikolweni. Apha ke banomdla kwisikhundla sakhe kwisihloko bandwidth link. Ngamafutshane, wayefuna ukwazi ukuba abantu abaninzi abavela kwicala ngalinye uyakwazi ukuthetha ucingo yefoni efanayo (ngaphandle kokuphazamisa nokuqondana kunye ukuvakala).

Benze ngayo kakade, yaye, njengoko kanti, kakhulu ichanekile. Umzekelo, i-Nyquist ngo-1928 lubonisa ukuba xa umjikelo isigxina uphawu isikhewu uyalingana isiqingatha ixesha phinda kakhulu, ngoko ke kwakhona.

D = 1 / 2F,

apho:

D - kuvumelekile uphawu ixesha iyaphela;

F- frequency ophezulu eziqulethwe spectrum umqondiso.

Nyquist ngokufanelekileyo kucingelwa ukuba ifowuni uphawu odiyo ukuba uluhlu rhoqo 3 kHz, kunokwenzeka ukuba strobe kumaza amaxesha 6000 ngomzuzwana kunye kulahlekelwa ingcaciso eluncedo kwi.

uqikelelo ezinjalo ngqindilili kwaye ongenantandabuzo ukuvumela mbali mihla inzululwazi ukusuka kumazwe Western endaweni ingcamango "Nyquist theorem" Igama yombhali. Nyquist theorem - yiloo igama theorem Nyquist kuzo iincwadi zezifundo ezininzi yaseYurophu American. Nakuba kunjalo, kuyinto enye into ukucebisa, nokuba yinto akanqwanqwi naqiniswa yi isiko, yaye enye into - ukubonisa. Theorem yohlukile elikuwo okanye hypothesis, ukuba ngokwenkcazo kufuna bubungqina.

Apha kuyimfuneko ukuba ndothulele umnqwazi abahlobo bethu Western. Priority Nyquist kwi ukucikideka "Nyquist theorem" akukho iimbambano omnye.

Ngaphandle inqanaba sezingeni eliphezulu ulwazi lwemathematika aphezulu akunakwenzeka ukuba baqonde indlela khulu aliqulunqileyo Nyquist theorem. Ubungqina isekelwe amaza kelelo ukuba acacisa inani Kotel'nikova ( "ukucwangcisa" zawo pulses ezimfutshane).

Loo isiseko theoretical ixesha ubuncinane uphawu ukubetha kusinika ithuba lokusebenzisa mobile phones namhlanje, kwakunye Techno phantsi umfanekiso processing, umculo kunye nezinye iintlobo ezininzi umxholo.