Nyquist Theorem - ngesisekelo ezincwadini zanamuhla Imininingwane ubuchwepheshe

Bambalwa impumelelo owaba nethonya elikhulu ngakho ukuthuthukiswa zokuxhumana kanye nokwaziswa nobuchwepheshe, njengoba Nyquist theorem. Ngokwengxenye enkulu, lokhu usosayensi uyikhazimulisile ezweni lethu engengaphansi kwengu-SP Queens, noma NJENGOBA Popov. Kungenzeka ukuthi Kotelnikov eyaziwa ngaphandle Russia nakakhulu kunangesikhathi wobaba.

Lokhu udumo has incazelo yalo. Nyquist theorem waba isisekelo ezicatshangelwayo zezinkolelo-zonke izimpahla digital yesimanje ezisetshenziselwa zokuxhumana. Kusekelwe isimiso digitizing neyodwa isignali noma isithombe. It kudala izimo ukubala yokuxhumana multi-umzila yebhangqa isignali. Ngenxa Nyquist theorem, ungayibuyisela esinomsindo isignali "Ragged", ukudala amasosha omzimba. amasu mfihlo nayo isekelwe lokhu ifayela echaza ifomu. Mhlawumbe angathola ezinye izinhlelo zokusebenza ewusizo.

Umbhali ukubaluleka enjalo sokuthuthukiswa umsakazo umsebenzi theory wazalwa ngo-1908 e Kazan. Uyise wayengumGreki uprofesa waseyunivesithi, unjiniyela ezidumile sezibalo Aleksandr Petrovich Kotelnikov, ngakho uma kuziwa ufuzo, isayensi e Victor Alexandrovich waba 'igazi'. Ngemva kokuthola iziqu eMoscow Energy Institute, le nsizwa waya iziqu esikoleni. Lapha ke unesithakazelo ngesihloko komkhawulokudonsa isixhumanisi yakhe umthamo. Ngamafuphi nje, wayefuna ukwazi ukuthi bangaki abantu ngala nangale angakhuluma okufanayo yocingo ngocingo (ngaphandle kokubandlulula ekuqondisisaneni kanye intelligibility).

Imibono ngakho kakade, ngisho, kwacaca ukuthi, olunembile ngempela. Ngokwesibonelo, ngo-1928 Nyquist sasikisela ukuthi uma umjikelezo nejoka isignali igebe ilingana isigamu kwenkathi nobuningi eliphakeme ke ingabuyiswa.

D = 1 / 2F,

lapho:

D - kuvunyelwe isignali isikhathi ubalekela;

F- imvamisa esiphezulu eziqukethwe bohlu isignali.

Nyquist okunengqondo bazitshela ukuthi isiginali umsindo ucingo kokuba ibanga lokuvama 3 kHz, kungenzeka ukuba Strobe at a imvamisa izikhathi 6000 ngomzuzwana ngaphandle ukulahlekelwa ulwazi oluwusizo.

ukucabanga ngaleyo ndlela ngesibindi enembile ukuvumela izazi-mlando zanamuhla nesayensi kusukela amazwe aseNtshonalanga ukuthi esikhundleni nombono wokuthi "Nyquist Theorem" igama lombhali. Nyquist theorem - yilokho igama ifayela echaza ifomu Nyquist sika izincwadi amaningi aseYurophu futhi American. Nokho, enye into ukuphakamisa, ngisho noma kuyinto nesibindi esikhulu kuqinisekiswa umkhuba, futhi enye into - ukuba kufakazelwe. Theorem iyahluka kwenye axioms noma umbono, ukuthi uma silinganisa udinga ubufakazi.

Lapha kubalulekile ukuthi ngincome abangane bethu Western. Priority Nyquist ku ubufakazi "Nyquist Theorem" akukho ukungezwani eyodwa.

Ngaphandle ezingeni ngokwanele lelisetulu lelwati wezibalo ephakeme akunakwenzeka ukuba baqonde indlela exquisitely zavela Nyquist theorem. Ubufakazi kusekelwe umumo gagasi isilinganiselo elicacisa inombolo Kotel'nikova ( "ugobe" zalo by pulses iDemo).

nsuku okunjalo theory isikhathi esincane isignali ishayela kusinikeza ithuba ukusebenzisa omakhalekhukhwini namuhla, kanye nohlelo lwezinombolo olubizwa futhi equliswa processing image, umculo kanye nezinye izinhlobo eziningi kokuqukethwe.