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Cluster feeds have been widely adopted as multibeam antenna feeds for communications satellites because they can realize high edge levels. A low-level feed system in which amplifiers are connected after beam-forming networks is especially effective in reducing the feed loss. The beam-forming network is not required to withstand high powers. This system is promising as a feed system of a multibeam antenna that needs to transmit high power. However, it is difficult to equalize the operational level of amplifiers in a low-level feed system. This paper proposes a hybrid low-level feed system that can equalize the operational levels of amplifiers in order to use the amplifiers more efficiently. Analysis shows properties of a design of an antenna that adopted this system. Antenna elements and beam-forming networks were produced. The primary patterns were measured, and the secondary patterns were calculated using these results. A comparison of the design with the calculation results shows that a multibeam antenna with high gain and low side lobes is realizable with this system. The components into which high power is input, are proved capable of withstanding high power and verified the generated level of PIM. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(11): 35–43, 2001 [ABSTRACT FROM AUTHOR]