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arXiv · 1905.04095

Phase retrieval for wide-band signals

Philippe Jaming·Karim Kellay·Rolando Perez Iii
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Abstract

This study investigates the phase retrieval problem for wide-band signals. We solve the following problem: given f $\in$ L 2 (R) with Fourier transform in L 2 (R, e^{2c|x|} dx), we find all functions g $\in$ L 2 (R) with Fourier transform in L 2 (R, e^{2c|x| dx}), such that |f (x)| = |g(x)| for all x $\in$ R. To do so, we first translate the problem to functions in the Hardy spaces on the disc via a conformal bijection, and take advantage of the inner-outer factorization. We also consider the same problem with additional constraints involving some transforms of f and g, and determine if these constraints force uniqueness of the solution.

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Philippe Jaming, Karim Kellay, Rolando Perez Iii. 2019-05-10. Phase retrieval for wide-band signals. https://arxiv.org/abs/1905.04095

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