Design Considerations for a Low-frequency Vivaldi Array Element.

A cavity-backed Vivaldi antenna is suggested as dual-polarization array element for the low-frequency instrument of the Square Kilometer Array (SKA) project. A design strategy aimed at maximizing the sensitivity for such an array element is described. As an example, an antenna was obtained, with a sensitivity higher than 10cm²/K in the operative bandwidth and in the 45° sky coverage angle, for each polarization. [ABSTRACT FROM AUTHOR]