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Coronal mass ejections (CMEs) are large-scale expulsions of plasma andmagnetic fields from the Sun into the heliosphere and are the most importantdriver of space weather. The geo-effectiveness of a CME is primarily determinedby its magnetic field strength and topology. Measurement of CME magneticfields, both in the corona and heliosphere, is essential for improving spaceweather forecasting. Observations at radio wavelengths can provide severalremote measurement tools for estimating both strength and topology of the CMEmagnetic fields. Among them, gyrosynchrotron (GS) emission produced bymildly-relativistic electrons trapped in CME magnetic fields is one of thepromising methods to estimate magnetic field strength of CMEs at lower andmiddle coronal heights. However, GS emissions from some parts of the CME aremuch fainter than the quiet Sun emission and require high dynamic range (DR)imaging for their detection. This thesis presents a state-of-the-artcalibration and imaging algorithm capable of routinely producing high DRspectropolarimetric snapshot solar radio images using data from a newtechnology radio telescope, the Murchison Widefield Array. This allows us todetect much fainter GS emissions from CME plasma at much higher coronalheights. For the first time, robust circular polarization measurements havebeen jointly used with total intensity measurements to constrain the GS modelparameters, which has significantly improved the robustness of the estimated GSmodel parameters. A piece of observational evidence is also found thatroutinely used homogeneous and isotropic GS models may not always be sufficientto model the observations. In the future, with upcoming sensitive telescopesand physics-based forward models, it should be possible to relax some of theseassumptions and make this method more robust for estimating CME plasmaparameters at coronal heights.

Deciphering Radio Emission from Solar Coronal Mass Ejections using High-fidelity Spectropolarimetric Radio Imaging