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引言欧洲空间局计划在八十年代发射的全欧通信卫星,将为欧洲提供高质量的区域通信。天线的基本结构是一个偏置的抛物面反射器,它在11—14千兆赫频段内发送或接收双线极化或圆极化信号。偏置反射器对线极化引起的去极化,可用一个“匹配馈源”来补偿。该馈源可使馈源辐射口径上的切向电场和非对称反射器焦平面场匹配。在这类馈源中由HE_(11)和HE_(21)模的适当迭加获得匹配场。
Introduction All-Europe communications satellites that the European Space Agency plans to launch in the 1980s will provide Europe with high-quality regional communications. The basic structure of the antenna is a biased parabolic reflector that transmits or receives two-wire polarized or circularly polarized signals in the 11-14 GHz band. The depolarization caused by the linear polarization of the biased reflector can be compensated by a “matching feed”. This feed allows the tangential electric field at the feed radiation aperture to be matched with the asymmetric reflector focal plane field. In this kind of feed, the matching field is obtained by proper superposition of HE_ (11) and HE_ (21) modes.