NFFT: Algorithm for irregular sampling
نویسندگان
چکیده
The nonuniform discrete Fourier transform (NDFT), used in many processing schemes, can be computed using a fast algorithm known as the non uniform fast Fourier transform (NFFT). The NFFT is not a new algorithm, but it is an approximation scheme that can be use to calculate an approximate spectrum. In one dimension, computational complexity of the NFFT is O(NlogN) which is a dramatic improvement from the O(N) complexity of the NDFT. This algorithm can be easily extended to higher dimensions.
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