Dual reflector type multi-beam antenna for communication satellites

To increase the channel capacity of the system by the re-use of frequency bands and to use the satellite in multipurpose applications, the satellite should have a multibeam antenna on board. This paper describes the design method and experimental results of the dual reflector type multibeam antenna for communication satellites. This antenna consists of main reflector, subreflector and multiple primary feed horns. Its antenna reflector curves are designed so as not to degrade the antenna efficiency in spite of multifeed arrangements. The calculation method to determine reflector curves for such a multibeam antenna, the design example for Japanese domestic communication satellites, calculations of theoretical properties and experimental results obtained from a fabricated seven-beam model antenna are described. From these results this type antenna is found favorable for multibeam antenna use in satellite communication.