Video: Dab tsi yog qhov tseem ceeb ntawm sampling theorem?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Sampling Theorem . Ib tseem ceeb qhov teeb meem hauv kev kuaj yog kev txiav txim siab ntawm kev kuaj zaus. Peb xav kom txo qis kev kuaj zaus kom txo tau cov ntaub ntawv loj, yog li txo cov kev siv computer complexity nyob rau hauv cov ntaub ntawv ua thiab cov nqi rau cov ntaub ntawv cia thiab kis tau tus mob.
Ntawm no, vim li cas peb thiaj li siv cov qauv theorem?
Txhawm rau ua cov teeb liab no hauv computer, peb yuav tsum hloov cov teeb liab mus rau "digital". Thaum lub teeb liab analog yog txuas mus rau ob lub sij hawm thiab amplitude, lub teeb liab digital yog discrete nyob rau hauv ob lub sij hawm thiab amplitude. Txhawm rau hloov lub teeb liab los ntawm lub sij hawm tas mus li mus rau lub sij hawm tsis sib xws, tus txheej txheem hu ua kev kuaj yog siv.
Tsis tas li ntawd, qhov piv txwv theorem txiav txim siab li cas? Cov Sampling Theorem Cov theorem hais tias, yog tias lub sijhawm ua haujlwm, f (t), tsis muaj zaus ntawm W hertz lossis siab dua, ces nws yog kiag li txiav txim siab los ntawm muab tus nqi ntawm kev ua haujlwm ntawm cov ntsiab lus sib nrug (2W)−1 sib nrug. Cov kev kuaj nqi 2w cov qauv ib ob yog hu ua Nyquist tus nqi.
Yog li ntawd, dab tsi yog qhov tseem ceeb ntawm kev ntsuas tus lej?
Yog li qhov siab dua tus qauv tus nqi , ntau cov qauv ib ob thiab ntau dua qhov zoo ntawm lub suab. Tab sis nco ntsoov qhov siab dua tus qauv tus nqi qhov loj dua cov ntaub ntawv audio thiab ntau lub zog ua koj lub computer xav tau. Cov tus qauv tus nqi koj xaiv nyob ntawm seb koj lub suab yuav siv li cas.
Vim li cas Nyquist theorem tseem ceeb?
Cov Nyquist theorem tsim lub hauv paus ntsiab lus ntawm sampling nruam signals los hloov lawv mus rau digital signals. Hauv kev sib txuas lus theory, lub Nyquist theorem yog ib qho qauv qhia tias ob qhov qauv ib lub voj voog yog txhua yam uas xav tau los sawv cev rau cov teeb liab analog digitally.
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