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arXiv · 1603.01592

Phase Retrieval of Real-Valued Signals in a Shift-Invariant Space

Yang Chen·Cheng Cheng·Qiyu Sun·Haichao Wang
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Abstract

Phase retrieval arises in various fields of science and engineering and it is well studied in a finite-dimensional setting. In this paper, we consider an infinite-dimensional phase retrieval problem to reconstruct real-valued signals living in a shift-invariant space from its phaseless samples taken either on the whole line or on a set with finite sampling rate. We find the equivalence between nonseparability of signals in a linear space and its phase retrievability with phaseless samples taken on the whole line. For a spline signal of order $N$, we show that it can be well approximated, up to a sign, from its noisy phaseless samples taken on a set with sampling rate $2N-1$. We propose an algorithm to reconstruct nonseparable signals in a shift-invariant space generated by a compactly supported continuous function. The proposed algorithm is robust against bounded sampling noise and it could be implemented in a distributed manner.

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Yang Chen, Cheng Cheng, Qiyu Sun, Haichao Wang. 2016-03-04. Phase Retrieval of Real-Valued Signals in a Shift-Invariant Space. https://arxiv.org/abs/1603.01592

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