Design of a Simultaneous Center-Fed X/Ka-Band SATCOM Reflector Antenna with Replacable C-Band Option

A 1.5m tri-band (C-, X- and Ka-band) center-fed SAT-COM terminal has been designed for shipboard applications. The terminal has two independent replaceable feeds; C-band and simultaneous X/Ka-band. Offset prime-focus and dual-reflector designs are optimum from a performance standpoint for a reflector of this electrical size, however the scarcity of real estate and other mechanical considerations on shipboard drives the design to a center-fed type. Of the available center-fed reflector types, a shaped ring-focus configuration was chosen since the ring-focus reflector has several advantages over Cassegrain/Gregorian types for reflectors in this electrical size range. The reflector antenna shape is derived numerically utilizing GO shaping techniques while the feeds are designed using the BOR MoM and PO methods. The resulting antenna has been constructed and tested, and results are presented.