Antenna Design

Each MWA antenna is a small phased array, or "tile", operating over 80-300 MHz. The essential features of each tile are:

16 dual-linear-polarization, wide-beamwidth antenna elements over a ground screen
elements arranged in a planar, 4x4 pattern with 1.07-meter spacing corresponding to half a wavelength at 140 MHz
low-noise amplifiers (LNAs) integral to each antenna element
an analog RF beamformer that combines the 16 signals of each polarization with appropriate delays to form a beam 15-50° wide (FWHM), depending on frequency

Details of the antenna design can be found here.