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arXiv · 1609.02448

Parallel Calibration for Sensor Array Radio Interferometers

Martin Brossard·Mohammed Nabil El Korso·Marius Pesavento·Rémy Boyer·Pascal Larzabal·Stefan J. Wijnholds
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Abstract

In order to meet the theoretically achievable imaging performance, calibration of modern radio interferometers is a mandatory challenge, especially at low frequencies. In this perspective, we propose a novel parallel iterative multi-wavelength calibration algorithm. The proposed algorithm estimates the apparent directions of the calibration sources, the directional and undirectional complex gains of the array elements and their noise powers, with a reasonable computational complexity. Furthermore, the algorithm takes into account the specific variation of the aforementioned parameter values across wavelength. Realistic numerical simulations reveal that the proposed scheme outperforms the mono-wavelength calibration scheme and approaches the derived constrained Cram\'er-Rao bound even with the presence of non-calibration sources at unknown directions, in a computationally efficient manner.

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Martin Brossard, Mohammed Nabil El Korso, Marius Pesavento, Rémy Boyer, Pascal Larzabal, Stefan J. Wijnholds. 2016-09-08. Parallel Calibration for Sensor Array Radio Interferometers. https://arxiv.org/abs/1609.02448

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