Phase retrieval from Fourier measurements with masks

Abstract

<p style='text-indent:20px;'>This paper concerns the problem of phase retrieval from Fourier measurements with random masks. Here we focus on researching two kinds of random masks. Firstly, we utilize the Fourier measurements with real masks to estimate a general signal <inline-formula><tex-math id="M1">\begin{document}$ \mathit{\boldsymbol{x}}_0\in \mathbb{R}^d $\end{document}</tex-math></inline-formula> in noiseless case when <inline-formula><tex-math id="M2">\begin{document}$ d $\end{document}</tex-math></inline-formula> is even. It is demonstrated that <inline-formula><tex-math id="M3">\begin{document}$ O(\log^2d) $\end{document}</tex-math></inline-formula> real random masks are able to ensure accurate recovery of <inline-formula><tex-math id="M4">\begin{document}$ \mathit{\boldsymbol{x}}_0 $\end{document}</tex-math></inline-formula>. Then we find that such real masks are not adaptable to reconstruct complex signals of even dimension. Subsequently, we prove that <inline-formula><tex-math id="M5">\begin{document}$ O(\log^4d) $\end{document}</tex-math></inline-formula> complex masks are enough to stably estimate a general signal <inline-formula><tex-math id="M6">\begin{document}$ \mathit{\boldsymbol{x}}_0\in \mathbb{C}^d $\end{document}</tex-math></inline-formula> under bounded noise interference, which extends E. Candès et al.'s work. Meanwhile, we establish tighter error estimations for real signals of even dimensions or complex signals of odd dimensions by using <inline-formula><tex-math id="M7">\begin{document}$ O(\log^2d) $\end{document}</tex-math></inline-formula> real masks. Finally, we intend to tackle with the noisy phase problem about an <inline-formula><tex-math id="M8">\begin{document}$ s $\end{document}</tex-math></inline-formula>-sparse signal by a robust and efficient approach, namely, two-stage algorithm. Based on the stable guarantees for general signals, we show that the <inline-formula><tex-math id="M9">\begin{document}$ s $\end{document}</tex-math></inline-formula>-sparse signal <inline-formula><tex-math id="M10">\begin{document}$ \mathit{\boldsymbol{x}}_0 $\end{document}</tex-math></inline-formula> can be stably recovered from composite measurements under near-optimal sample complexity up to a <inline-formula><tex-math id="M11">\begin{document}$ \log $\end{document}</tex-math></inline-formula> factor, namely, <inline-formula><tex-math id="M12">\begin{document}$ O(s\log(\frac{ed}{s})\log^4(s\log(\frac{ed}{s}))) $\end{document}</tex-math></inline-formula></p>

Topics & Concepts