Properties of spatial coupling in compressed sensing

Francesco Caltagirone; Lenka Zdeborová

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arXiv · 1401.6380

Properties of spatial coupling in compressed sensing

Francesco Caltagirone·Lenka Zdeborová

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Abstract

In this paper we address a series of open questions about the construction of spatially coupled measurement matrices in compressed sensing. For hardware implementations one is forced to depart from the limiting regime of parameters in which the proofs of the so-called threshold saturation work. We investigate quantitatively the behavior under finite coupling range, the dependence on the shape of the coupling interaction, and optimization of the so-called seed to minimize distance from optimality. Our analysis explains some of the properties observed empirically in previous works and provides new insight on spatially coupled compressed sensing.

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Francesco Caltagirone, Lenka Zdeborová. 2014-01-24. Properties of spatial coupling in compressed sensing. https://arxiv.org/abs/1401.6380

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