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arXiv · 2401.16044

Numerical Stability of DFT Computation for Signals with Structured Support

Charantej Reddy Pochimireddy·Aditya Siripuram·Brad Osgood
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Abstract

We consider the problem of building numerically stable algorithms for computing Discrete Fourier Transform (DFT) of $N$- length signals with known frequency support of size $k$. A typical algorithm, in this case, would involve solving (possibly poorly conditioned) system of equations, causing numerical instability. When $N$ is a power of 2, and the frequency support is a random subset of $\mathbb{Z}_N$, we provide an algorithm that has (a possibly optimal) $O(k \log k)$ complexity to compute the DFT while solving system of equations that are $O(1)$ in size.

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Charantej Reddy Pochimireddy, Aditya Siripuram, Brad Osgood. 2024-01-29. Numerical Stability of DFT Computation for Signals with Structured Support. https://doi.org/10.1109/isit57864.2024.10619543

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