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arXiv · 2102.12514

Computing the Discrete Fourier Transform of signals with spectral frequency support

P Charantej Reddy·V S S Prabhu Tej·Aditya Siripuram·Brad Osgood
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Abstract

We consider the problem of finding the Discrete Fourier Transform (DFT) of $N-$ length signals with known frequency support of size $k$. When $N$ is a power of 2 and the frequency support is a spectral set, we provide an $O(k \log k)$ algorithm to compute the DFT. Our algorithm uses some recent characterizations of spectral sets and is a generalization of the standard radix-2 algorithm.

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P Charantej Reddy, V S S Prabhu Tej, Aditya Siripuram, Brad Osgood. 2021-02-24. Computing the Discrete Fourier Transform of signals with spectral frequency support. https://doi.org/10.1109/isit45174.2021.9518104

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