Design of Tight Minimum-Sidelobe Windows by Riemannian Newton's Method

Daichi Kitahara; Kohei Yatabe

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arXiv · 2111.01593

Design of Tight Minimum-Sidelobe Windows by Riemannian Newton's Method

Daichi Kitahara·Kohei Yatabe

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Abstract

The short-time Fourier transform (STFT), or the discrete Gabor transform (DGT), has been extensively used in signal analysis and processing. Their properties are characterized by a window function. For signal processing, designing a special window called tight window is important because it is known to make DGT-domain processing robust to error. In this paper, we propose a method of designing tight windows that minimize the sidelobe energy. It is formulated as a constrained spectral concentration problem, and a Newton's method on an oblique manifold is derived to efficiently obtain a solution. Our numerical example showed that the proposed algorithm requires only several iterations to reach a stationary point.

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BibTeX RIS

Daichi Kitahara, Kohei Yatabe. 2021-11-02. Design of Tight Minimum-Sidelobe Windows by Riemannian Newton's Method. https://arxiv.org/abs/2111.01593

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