Multibeam Antennas based on phased arrays: an overview on recent ESA developments

The aim of the paper is to provide an overview on the activities recently promoted by the European Space Agency (ESA) on satellite multibeam antennas based on phased arrays. The attention is focused on antennas generating multiple spot beams coverages with a single main aperture. In particular, solutions based on direct radiating arrays, active discrete lenses, and confocal reflectors will be discussed. These solutions present some challenges but also some advantages as compared to conventional architectures based on multi reflectors with a single feed per beam. ESA is supporting since several years activities in this challenging domain.