Ionospheric Modelling using GPS to Calibrate the MWA. I: Comparison of First Order Ionospheric Effects between GPS Models and MWA Observations

B. S. Arora, J. Morgan, S. M. Ord, S. J. Tingay, N. Hurley-Walker, M. Bell, G. Bernardi, N. D R Bhat, F. Briggs, J. R. Callingham, A. A. Deshpande, K. S. Dwarakanath, A. Ewall-Wice, L. Feng, B. Q. For, P. Hancock, B. J. Hazelton, L. Hindson, Daniel Jacobs, M. Johnston-HollittA. D. Kapińska, N. Kudryavtseva, E. Lenc, B. McKinley, D. Mitchell, D. Oberoi, A. R. Offringa, B. Pindor, P. Procopio, J. Riding, L. Staveley-Smith, R. B. Wayth, C. Wu, Q. Zheng, Judd Bowman, R. J. Cappallo, B. E. Corey, D. Emrich, R. Goeke, L. J. Greenhill, D. L. Kaplan, J. C. Kasper, E. Kratzenberg, C. J. Lonsdale, M. J. Lynch, S. R. McWhirter, M. F. Morales, E. Morgan, T. Prabu, A. E E Rogers, A. Roshi, N. Udaya Shankar, K. S. Srivani, R. Subrahmanyan, M. Waterson, R. L. Webster, A. R. Whitney, A. Williams, And C L Williams

Research output: Contribution to journalArticle

11 Scopus citations

Abstract

We compare first-order (refractive) ionospheric effects seen by the MWA with the ionosphere as inferred from GPS data. The first-order ionosphere manifests itself as a bulk position shift of the observed sources across an MWA field of view. These effects can be computed from global ionosphere maps provided by GPS analysis centres, namely the CODE. However, for precision radio astronomy applications, data from local GPS networks needs to be incorporated into ionospheric modelling. For GPS observations, the ionospheric parameters are biased by GPS receiver instrument delays, among other effects, also known as receiver DCBs. The receiver DCBs need to be estimated for any non-CODE GPS station used for ionosphere modelling. In this work, single GPS station-based ionospheric modelling is performed at a time resolution of 10 min. Also the receiver DCBs are estimated for selected Geoscience Australia GPS receivers, located at Murchison Radio Observatory, Yarragadee, Mount Magnet and Wiluna. The ionospheric gradients estimated from GPS are compared with that inferred from MWA. The ionospheric gradients at all the GPS stations show a correlation with the gradients observed with the MWA. The ionosphere estimates obtained using GPS measurements show promise in terms of providing calibration information for the MWA.

Original languageEnglish (US)
Article numbere029
JournalPublications of the Astronomical Society of Australia
Volume32
DOIs
StatePublished - Feb 16 2015

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Keywords

  • atmospheric effects
  • techniques: interferometric

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Arora, B. S., Morgan, J., Ord, S. M., Tingay, S. J., Hurley-Walker, N., Bell, M., Bernardi, G., Bhat, N. D. R., Briggs, F., Callingham, J. R., Deshpande, A. A., Dwarakanath, K. S., Ewall-Wice, A., Feng, L., For, B. Q., Hancock, P., Hazelton, B. J., Hindson, L., Jacobs, D., ... Williams, A. C. L. (2015). Ionospheric Modelling using GPS to Calibrate the MWA. I: Comparison of First Order Ionospheric Effects between GPS Models and MWA Observations. Publications of the Astronomical Society of Australia, 32, [e029]. https://doi.org/10.1017/pasa.2015.29