The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform

Aatto Laaksonen - One of the best experts on this subject based on the ideXlab platform.

Ryuji Hirayama - One of the best experts on this subject based on the ideXlab platform.

  • Nonuniform sampled scalar diffraction calculation using nonuniform Fast Fourier Transform
    Optics Letters, 2013
    Co-Authors: Tomoyoshi Shimobaba, Takashi Kakue, Minoru Oikawa, Naohisa Okada, Yutaka Endo, Ryuji Hirayama
    Abstract:

    Scalar diffraction calculations, such as the angular spectrum method (ASM) and Fresnel diffraction, are widely used in the research fields of optics, x rays, electron beams, and ultrasonics. It is possible to accelerate the calculation using Fast Fourier Transform (FFT); unfortunately, acceleration of the calculation of nonuniform sampled planes is limited due to the property of the FFT that imposes uniform sampling. In addition, it gives rise to wasteful sampling data if we calculate a plane having locally low and high spatial frequencies. In this Letter, we developed nonuniform sampled ASM and Fresnel diffraction to improve the problem using the nonuniform FFT.

Tie Jun Cui - One of the best experts on this subject based on the ideXlab platform.

  • A sparse data Fast Fourier Transform (SDFFT)
    IEEE Transactions on Antennas and Propagation, 2003
    Co-Authors: A.a. Aydiner, Weng Cho Chew, Jiming Song, Tie Jun Cui
    Abstract:

    A multilevel algorithm that efficiently Fourier Transforms sparse spatial data to sparse spectral data with controllable error is presented. The algorithm termed "sparse data Fast Fourier Transform" (SDFFT) is particularly useful for signal processing applications where only part of the k-space is to be computed - Regardless of whether it is a regular region like an angular section of the Ewald sphere or it consists of completely arbitrary points scattered in the k-space. In addition, like the various nonuniform Fast Fourier Transforms, the O(N log N) algorithm can deal with a sparse, nonuniform spatial domain. In this paper, the parabolic reflector antenna problem is studied as an example to demonstrate its use in the computation of far-field patterns due to arbitrary aperture antennas and antenna arrays. The algorithm is also promising for various applications such as back-projection tomography, diffraction tomography, and synthetic aperture radar imaging.link_to_subscribed_fulltex

Fredrik Hedman - One of the best experts on this subject based on the ideXlab platform.

Tomoyoshi Shimobaba - One of the best experts on this subject based on the ideXlab platform.

  • Nonuniform sampled scalar diffraction calculation using nonuniform Fast Fourier Transform
    Optics Letters, 2013
    Co-Authors: Tomoyoshi Shimobaba, Takashi Kakue, Minoru Oikawa, Naohisa Okada, Yutaka Endo, Ryuji Hirayama
    Abstract:

    Scalar diffraction calculations, such as the angular spectrum method (ASM) and Fresnel diffraction, are widely used in the research fields of optics, x rays, electron beams, and ultrasonics. It is possible to accelerate the calculation using Fast Fourier Transform (FFT); unfortunately, acceleration of the calculation of nonuniform sampled planes is limited due to the property of the FFT that imposes uniform sampling. In addition, it gives rise to wasteful sampling data if we calculate a plane having locally low and high spatial frequencies. In this Letter, we developed nonuniform sampled ASM and Fresnel diffraction to improve the problem using the nonuniform FFT.