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arXiv · 1907.10773

Inverting Spectrogram Measurements via Aliased Wigner Distribution Deconvolution and Angular Synchronization

Michael Perlmutter·Sami Merhi·Aditya Viswanathan·Mark Iwen
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Abstract

We propose a two-step approach for reconstructing a signal ${\bf x}\in\mathbb{C}^d$ from subsampled short-time Fourier transform magnitude (spectogram) measurements: First, we use an aliased Wigner distribution deconvolution approach to solve for a portion of the rank-one matrix ${\bf \widehat{{\bf x}}}{\bf \widehat{{\bf x}}}^{*}.$ Second, we use angular syncrhonization to solve for ${\bf \widehat{{\bf x}}}$ (and then for ${\bf x}$ by Fourier inversion). Using this method, we produce two new efficient phase retrieval algorithms that perform well numerically in comparison to standard approaches and also prove two theorems, one which guarantees the recovery of discrete, bandlimited signals ${\bf x}\in\mathbb{C}^{d}$ from fewer than $d$ STFT magnitude measurements and another which establishes a new class of deterministic coded diffraction pattern measurements which are guaranteed to allow efficient and noise robust recovery.

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Michael Perlmutter, Sami Merhi, Aditya Viswanathan, Mark Iwen. 2019-07-24. Inverting Spectrogram Measurements via Aliased Wigner Distribution Deconvolution and Angular Synchronization. https://arxiv.org/abs/1907.10773

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