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arXiv · 2505.05388

On Multiangle Discrete Fractional Periodic Transforms

Christian Oswald·Franz Pernkopf
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Abstract

The efficient multiangle centered discrete fractional Fourier transform (MA-CDFRFT) [1] has proven to be a useful tool for time-frequency analysis; in this paper, we generalize the MA-CDFRFT to general M -periodic transforms, which, among others, include the standard discrete Fourier, discrete sine, discrete cosine, Hadamard and discrete Hartley transform. Furthermore, we exploit the symmetries inherent to the MA-CDFRFT and our novel multiangle standard discrete fractional Fourier transform (MA-DFRFT) to halve the number of FFTs needed to compute these transforms, which paves the way for applications in resource-constrained environments.

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Christian Oswald, Franz Pernkopf. 2025-05-08. On Multiangle Discrete Fractional Periodic Transforms. https://doi.org/10.1109/icassp55912.2026.11460624

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