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Interferometric arrays seeking to measure the 21 cm signal from the Epoch ofReionization must contend with overwhelmingly bright emission from foregroundsources. Accurate recovery of the 21 cm signal will require precise calibrationof the array, and several new avenues for calibration have been pursued inrecent years, including methods using redundancy in the antenna configuration.The newly upgraded Phase II of Murchison Widefield Array (MWA) is the firstinterferometer that has large numbers of redundant baselines while retaininggood instantaneous UV-coverage. This array therefore provides a uniqueopportunity to compare redundant calibration with sky-model based algorithms.In this paper, we present the first results from comparing both calibrationapproaches with MWA Phase II observations. For redundant calibration, we usethe package OMNICAL, and produce sky-based calibration solutions with theanalysis package Fast Holographic Deconvolution (FHD). There are threeprincipal results. (1) We report the success of OMNICAL on observations ofORBComm satellites, showing substantial agreement between redundant visibilitymeasurements after calibration. (2) We directly compare OMNICAL calibrationsolutions with those from FHD, and demonstrate these two different calibrationschemes give extremely similar results. (3) We explore improved calibration bycombining OMNICAL and FHD. We evaluate these combined methods using powerspectrum techniques developed for EoR analysis and find evidence for marginalimprovements mitigating artifacts in the power spectrum. These results arelikely limited by signal-to-noise in the six hours of data used, but suggestfuture directions for combining these two calibration schemes.

Comparing Redundant and Sky Model Based Interferometric Calibration: A First Look with Phase II of the MWA