Congreso: 29th ESA Antenna Workshop on Multiple Beams and Reconfigurable Antennas. ESTEC, Noordwijk, The Netherlands. 18-20 de Abril de 2007

Autores: V. García Carrera, A. Montesano, J. Campuzano, J. L. García Fernández, R. Caballero de la Vega, J. Grajal

Current requirements for coverage flexibility appearing in standard Ka-band missions are limited to steerable spot beams, but a significant number of missions in recent years have made use of more than one such antenna. For this reason, a Direct Radiating Array (DRA) could provide much greater beam shape flexibility together with a much greater number of beams, though separate transmit and receive antennas would be required. Two of the main challenges in the transmit DRA antenna are the High Power stage and the Thermal Control design. In one side, the RF power in a transmit DRA antenna could be distributed in every element of the DRA and differente components could be used; and in other side, every RF power stage solution could be associated to one or more Thermal Control designs according to the performances of every High Power Stage possibility. Thes two aspects in a transmit DRA antenna are being studied by EADS-CASA Espacio in the ESA porject "Transmit RE-Configurable Multi-Beam Antenna" for Ka band frecuencies. Different solutions for the High Power Stage (SSPA Ga As amplifiers, SSPA GaN amplifiers and Mini-TWT) and their advantages and disadvantages as components of a transmit DRA antenna are being analysed with differente Thermal Control designs which could be associated to the HP Stage.