Publication

Radio interferometric calibration using the SAGE algorithm

Kazemi, S., Yatawatta, S., Zaroubi, S., Lampropoulos, P., de Bruyn, A. G., Koopmans, L. V. E. & Noordam, J., Jun-2011, In : Monthly Notices of the Royal Astronomical Society. 414, 2, p. 1656-1666 11 p.

Research output: Contribution to journalArticleAcademicpeer-review

APA

Kazemi, S., Yatawatta, S., Zaroubi, S., Lampropoulos, P., de Bruyn, A. G., Koopmans, L. V. E., & Noordam, J. (2011). Radio interferometric calibration using the SAGE algorithm. Monthly Notices of the Royal Astronomical Society, 414(2), 1656-1666. https://doi.org/10.1111/j.1365-2966.2011.18506.x

Author

Kazemi, S. ; Yatawatta, S. ; Zaroubi, S. ; Lampropoulos, P. ; de Bruyn, A. G. ; Koopmans, L. V. E. ; Noordam, J. / Radio interferometric calibration using the SAGE algorithm. In: Monthly Notices of the Royal Astronomical Society. 2011 ; Vol. 414, No. 2. pp. 1656-1666.

Harvard

Kazemi, S, Yatawatta, S, Zaroubi, S, Lampropoulos, P, de Bruyn, AG, Koopmans, LVE & Noordam, J 2011, 'Radio interferometric calibration using the SAGE algorithm', Monthly Notices of the Royal Astronomical Society, vol. 414, no. 2, pp. 1656-1666. https://doi.org/10.1111/j.1365-2966.2011.18506.x

Standard

Radio interferometric calibration using the SAGE algorithm. / Kazemi, S.; Yatawatta, S.; Zaroubi, S.; Lampropoulos, P.; de Bruyn, A. G.; Koopmans, L. V. E.; Noordam, J.

In: Monthly Notices of the Royal Astronomical Society, Vol. 414, No. 2, 06.2011, p. 1656-1666.

Research output: Contribution to journalArticleAcademicpeer-review

Vancouver

Kazemi S, Yatawatta S, Zaroubi S, Lampropoulos P, de Bruyn AG, Koopmans LVE et al. Radio interferometric calibration using the SAGE algorithm. Monthly Notices of the Royal Astronomical Society. 2011 Jun;414(2):1656-1666. https://doi.org/10.1111/j.1365-2966.2011.18506.x


BibTeX

@article{0ac1e0c4f98d4952ba58442d074087f2,
title = "Radio interferometric calibration using the SAGE algorithm",
abstract = "The aim of the new generation of radio synthesis arrays such as LOw Frequency ARray (LOFAR) and Square Kilometre Array (SKA) is to achieve much higher sensitivity, resolution and frequency coverage than what is available now, especially at low frequencies. To accomplish this goal, the accuracy of the calibration techniques used is of considerable importance. Moreover, since these telescopes produce huge amounts of data, speed of convergence of calibration is a major bottleneck. The errors in calibration are due to system noise (sky and instrumental) as well as the estimation errors introduced by the calibration technique itself, which we call 'solver noise'. We define solver noise as the 'distance' between the optimal solution (the true value of the unknowns, uncorrupted by the system noise) and the solution obtained by calibration. We present the Space Alternating Generalized Expectation Maximization (SAGE) calibration technique, which is a modification of the Expectation Maximization algorithm, and compare its performance with the traditional least squares calibration based on the level of solver noise introduced by each technique. For this purpose, we develop statistical methods that use the calibrated solutions to estimate the level of solver noise. The SAGE calibration algorithm yields very promising results in terms of both accuracy and speed of convergence. The comparison approaches that we adopt introduce a new framework for assessing the performance of different calibration schemes.",
keywords = "methods: numerical, methods: statistical, techniques: interferometric",
author = "S. Kazemi and S. Yatawatta and S. Zaroubi and P. Lampropoulos and {de Bruyn}, {A. G.} and Koopmans, {L. V. E.} and J. Noordam",
note = "M1 - Journal Article",
year = "2011",
month = jun,
doi = "10.1111/j.1365-2966.2011.18506.x",
language = "English",
volume = "414",
pages = "1656--1666",
journal = "Monthly Notices of the Royal Astronomical Society",
issn = "0035-8711",
publisher = "Oxford University Press",
number = "2",

}

RIS

TY - JOUR

T1 - Radio interferometric calibration using the SAGE algorithm

AU - Kazemi, S.

AU - Yatawatta, S.

AU - Zaroubi, S.

AU - Lampropoulos, P.

AU - de Bruyn, A. G.

AU - Koopmans, L. V. E.

AU - Noordam, J.

N1 - M1 - Journal Article

PY - 2011/6

Y1 - 2011/6

N2 - The aim of the new generation of radio synthesis arrays such as LOw Frequency ARray (LOFAR) and Square Kilometre Array (SKA) is to achieve much higher sensitivity, resolution and frequency coverage than what is available now, especially at low frequencies. To accomplish this goal, the accuracy of the calibration techniques used is of considerable importance. Moreover, since these telescopes produce huge amounts of data, speed of convergence of calibration is a major bottleneck. The errors in calibration are due to system noise (sky and instrumental) as well as the estimation errors introduced by the calibration technique itself, which we call 'solver noise'. We define solver noise as the 'distance' between the optimal solution (the true value of the unknowns, uncorrupted by the system noise) and the solution obtained by calibration. We present the Space Alternating Generalized Expectation Maximization (SAGE) calibration technique, which is a modification of the Expectation Maximization algorithm, and compare its performance with the traditional least squares calibration based on the level of solver noise introduced by each technique. For this purpose, we develop statistical methods that use the calibrated solutions to estimate the level of solver noise. The SAGE calibration algorithm yields very promising results in terms of both accuracy and speed of convergence. The comparison approaches that we adopt introduce a new framework for assessing the performance of different calibration schemes.

AB - The aim of the new generation of radio synthesis arrays such as LOw Frequency ARray (LOFAR) and Square Kilometre Array (SKA) is to achieve much higher sensitivity, resolution and frequency coverage than what is available now, especially at low frequencies. To accomplish this goal, the accuracy of the calibration techniques used is of considerable importance. Moreover, since these telescopes produce huge amounts of data, speed of convergence of calibration is a major bottleneck. The errors in calibration are due to system noise (sky and instrumental) as well as the estimation errors introduced by the calibration technique itself, which we call 'solver noise'. We define solver noise as the 'distance' between the optimal solution (the true value of the unknowns, uncorrupted by the system noise) and the solution obtained by calibration. We present the Space Alternating Generalized Expectation Maximization (SAGE) calibration technique, which is a modification of the Expectation Maximization algorithm, and compare its performance with the traditional least squares calibration based on the level of solver noise introduced by each technique. For this purpose, we develop statistical methods that use the calibrated solutions to estimate the level of solver noise. The SAGE calibration algorithm yields very promising results in terms of both accuracy and speed of convergence. The comparison approaches that we adopt introduce a new framework for assessing the performance of different calibration schemes.

KW - methods: numerical

KW - methods: statistical

KW - techniques: interferometric

U2 - 10.1111/j.1365-2966.2011.18506.x

DO - 10.1111/j.1365-2966.2011.18506.x

M3 - Article

VL - 414

SP - 1656

EP - 1666

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 2

ER -

ID: 13528966