Ionospheric Modelling using GPS to Calibrate the MWA. II: Regional ionospheric modelling using GPS and GLONASS to estimate ionospheric gradients

Abstract

We estimate spatial gradients in the ionosphere using the Global Positioning System (GPS) and GLONASS (Russian global navigation system) observations, utilising data from multiple GPS stations in the vicinity of Murchison Radio-astronomy Observatory (MRO). In previous work the ionosphere was characterised using a single-station to model the ionosphere as a single layer of fixed height and this was compared with ionospheric data derived from radio astronomy observations obtained from the Murchison Widefield Array (MWA). Having made improvements to our data quality (via cycle slip detection and repair) and incorporating data from the GLONASS system, we now present a multi-station approach. These two developments significantly improve our modelling of the ionosphere. We also explore the effects of a variable-height model. We conclude that modelling the small-scale features in the ionosphere that have been observed with the MWA will require a much denser network of Global Navigation Satellite System (GNSS) stations than is currently available at the MRO.

arXiv comment15 pages, 12 Figures, paper accepted for publication in Publications of the Astronomical Society of Australia (PASA)

References in corpus (6)

• The Murchison Widefield Array: the Square Kilometre Array Precursor at low radio frequencies
• The Precision Array for Probing the Epoch of Reionization: 8 Station Results
• The Murchison Widefield Array: Design Overview
• GLEAM: The GaLactic and Extragalactic All-sky MWA survey
• Quantifying ionospheric effects on time-domain astrophysics with the Murchison Widefield Array
• Ionospheric modelling using GPS to calibrate the MWA. 1: Comparison of first order ionospheric effects between GPS models and MWA observations

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• A probabilistic approach to direction-dependent ionospheric calibration
• Probing the ionosphere by the pulsar B0950+08 with help of RadioAstron ground-space baselines
• Spatially constrained direction dependent calibration
• Probing Equatorial Ionospheric TEC at Sub-GHz Frequencies with Wide-Band (B4) uGMRT Interferometric Data