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arXiv · 2510.14873

Sampling Density Compensation using Fast Fourier Deconvolution

Rui Luo·Peng Hu·Haikun Qi
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Abstract

Density Compensation Function (DCF) is widely used in non-Cartesian MRI reconstruction, either for direct Non-Uniform Fast Fourier Transform (NUFFT) reconstruction or for iterative undersampled reconstruction. Current state-of-the-art methods involve time-consuming tens of iterations, which is one of the main hurdles for widespread application of the highly efficient non-Cartesian MRI. In this paper, we propose an efficient, non-iterative method to calculate DCF for arbitrary non-Cartesian $k$-space trajectories using Fast Fourier Deconvolution. Simulation experiments demonstrate that the proposed method is able to yield DCF for 3D non-Cartesian reconstruction in around 20 seconds, achieving orders of magnitude speed improvement compared to the state-of-the-art method while achieving similar reconstruction quality.

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Rui Luo, Peng Hu, Haikun Qi. 2025-10-16. Sampling Density Compensation using Fast Fourier Deconvolution. https://arxiv.org/abs/2510.14873

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