We report on the MIT Epoch of Reionization ( MITEoR ) experiment , a pathfinder low-frequency radio interferometer whose goal is to test technologies that improve the calibration precision and reduce the cost of the high-sensitivity 3D mapping required for 21 cm cosmology .
MITEoR accomplishes this by using massive baseline redundancy , which enables both automated precision calibration and correlator cost reduction .
We demonstrate and quantify the power and robustness of redundancy for scalability and precision .
We find that the calibration parameters precisely describe the effect of the instrument upon our measurements , allowing us to form a model that is consistent with \chi ^ { 2 } per degree of freedom < 1.2 for as much as 80 \% of the observations .
We use these results to develop an optimal estimator of calibration parameters using Wiener filtering , and explore the question of how often and how finely in frequency visibilities must be reliably measured to solve for calibration coefficients .
The success of MITEoR with its 64 dual-polarization elements bodes well for the more ambitious Hydrogen Epoch of Reionization Array ( HERA ) project and other next-generation instruments , which would incorporate many identical or similar technologies .