Title :
Semi-active reflector antennas
Author_Institution :
ESA-ESTEC, Noordwijk, Netherlands
fDate :
June 28 1993-July 2 1993
Abstract :
Semiactive multimatrix reflector antennas offer efficient reconfigurability for multibeam payloads and have growth potential. The basic idea is to introduce multiport hybrids or matrices between the amplifiers and the feed elements. These include four-port hybrid couplers and phase shifters, like Butler matrices. This allows one to change the excitations of the feed elements by low level control, while keeping the total power level at each module close to nominal for optimum DC to RF efficiency (in multicarrier mode). A semiactive multimatrix design has been selected for the L-band antennas of the INMARSAT III satellite with full earth coverage as well as for the ESA (European Space Agency) ARTEMIS mobile communication payload.<>
Keywords :
active antennas; multiport networks; phase shifters; reflector antenna feeds; satellite antennas; ARTEMIS mobile communication payload; Butler matrices; DC to RF efficiency; INMARSAT III satellite; L-band antennas; hybrid couplers; low level control; multimatrix reflector antennas; multiport hybrids; phase shifters; reconfigurability; semiactive multimatrix design; Butler matrix; Couplers; Feeds; L-band; Level control; Payloads; Phase shifters; Radio frequency; Radiofrequency amplifiers; Reflector antennas;
Conference_Titel :
Antennas and Propagation Society International Symposium, 1993. AP-S. Digest
Conference_Location :
Ann Arbor, MI, USA
Print_ISBN :
0-7803-1246-5
DOI :
10.1109/APS.1993.385441
