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The redshifted cosmological 21 cm signal emitted by neutral hydrogen duringthe first billion years of the universe is much fainter relative to othergalactic and extragalactic radio emissions, posing a great challenge towardsdetection of the signal. Therefore, precise instrumental calibration is a vitalprerequisite for the success of radio interferometers such as the MurchisonWidefield Array (MWA), which aim for a 21 cm detection. Over the previousyears, novel calibration techniques targeting the power spectrum paradigm ofEoR science have been actively researched and where possible implemented. Usingrecently acquired computation resources for the MWA, we test the fullcapabilities of the state-of-the-art calibration techniques available for theMWA EoR project, with a focus on both direction dependent and directionindependent calibration. Specifically, we investigate improvements that can bemade in the vital calibration stages of sky modelling, ionospheric correction,and compact source foreground subtraction as applied in the hybrid foregroundmitigation approach (one that combines both foreground subtraction andavoidance). Additionally, we investigate a method of ionospheric correctionusing interpolated ionospheric phase screens and assess its performance in thepower spectrum space. Overall, we identify a refined RTS calibrationconfiguration that leads to an at least 2 factor reduction of the EoR windowpower contamination at the $0.1 \; \text{hMpc}^{-1}$ scale. The improvementmarks a step further towards detecting the 21 cm signal using the MWA and theforthcoming SKA low telescope.

Optimising MWA EoR data processing for improved 21 cm power spectrum measurements -- fine-tuning ionospheric corrections