DIT algorithm faib cov ntu ua ntu zus rau Ib qhov piv txwv thiab khib.
Puas yog FFT algorithm faib cov kab ke mus rau?
1. Yog tias peb faib cov N point cov ntaub ntawv ib ntus mus rau ob N / 2 taw tes cov ntaub ntawv sib txuas f1(n) thiab f2(n) Raws li tus lej suav thiab khib tus lej ntawm x(n), ces xws li FFT algorithm yog hu ua decimation-in-time algorithm.
Dab tsi yog dit algorithm?
Kev txiav txim siab hauv lub sijhawm DIT algorithm yog siv los suav DFT ntawm N-point sequence. Lub tswv yim yog txhawm rau txhawm rau N-point ib ntus ua ob ntu, DFTs uas tuaj yeem muab tau los muab DFT ntawm thawj N-point ib ntus.
DIT FFT algorithm yog dab tsi?
Qhov kev txiav txim-hauv-lub sijhawm (DIT) radix-2 FFT recursively partitions ib DFT rau hauv ob ib nrab-ntev DFTs ntawm cov qauv txawm-indexed thiab khib-indexed sijhawm. … Lub radix-2 kev txiav txim siab-hauv-lub sijhawm thiab kev txiav txim siab-hauv-frequency ceev Fourier hloov pauv (FFTs) yog qhov yooj yim tshaj plaws FFT algorithms.
Yuav ua li cas ntau npaum li cas complex multiplications yuav tsum tau ua rau txhua FFT algorithm1 point a N 2 Logn B nlog2n C N 2 log2n D Tsis muaj qhov hais?
Kev piav qhia: Hauv txoj kev sib tshooj ntxiv, N-point cov ntaub ntawv thaiv muaj L cov ntaub ntawv tshiab cov ntsiab lus thiab ntxiv M-1 xoom thiab tus lej ntawm cov kev sib txuas uas xav tau hauv FFT algorithm yog (N / 2)log2N . Yog li, tus naj npawb ntawm complexmultiplications per output data point is [Nlog22N]/L.
