Phased array antennas demonstrator as a radio telescope - EMBRACE

For over a decade the radio astronomy community has been working towards the realization of a global project known as square kilometer array (SKA). This project is a radio telescope operational from 0.1 GHz to 25 GHz, with a square kilometer of overall collecting area, providing an increase in sensitivity of up to two orders of magnitude. To cover the entire frequency bandwidth, three possible concepts have been proposed. At lower end of the frequency spectrum an all digital dipole array has been proposed whereas at the higher end, a reflector array with a wide band feed has been proposed. In the mid-band, either a phased array or a focal plane array has been considered. In this paper we describe the design and development of a phased array concept, which has been proposed by the Europeans as their concept towards the SKA.