Super-Resolution of Point Sources via Convex Programming

Carlos Fernandez-Granda

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arXiv · 1507.07034

Super-Resolution of Point Sources via Convex Programming

Carlos Fernandez-Granda

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Abstract

We consider the problem of recovering a signal consisting of a superposition of point sources from low-resolution data with a cut-off frequency f. If the distance between the sources is under 1/f, this problem is not well posed in the sense that the low-pass data corresponding to two different signals may be practically the same. We show that minimizing a continuous version of the l1 norm achieves exact recovery as long as the sources are separated by at least 1.26/f. The proof is based on the construction of a dual certificate for the optimization problem, which can be used to establish that the procedure is stable to noise. Finally, we illustrate the flexibility of our optimization-based framework by describing extensions to the demixing of sines and spikes and to the estimation of point sources that share a common support.

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BibTeX RIS

Carlos Fernandez-Granda. 2015-07-24. Super-Resolution of Point Sources via Convex Programming. https://arxiv.org/abs/1507.07034

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