Multibeam active phased arrays for communications satellites

It is well known that an active phased array (APA) payload has the potential to overcome the flexibility limitations associated with conventional communications satellites. This article discusses the benefits and design drivers associated with APAs and features a deployed APA antenna architecture for multiple-beam applications that is modular in construction and programmable in performance. This architecture applies to both receive and transmit arrays. Some of the critical hardware that has been developed in support of this architecture is described. The article focuses on transmit APAs, as they tend to be more technologically challenging than receive APAs. Transmit APAs also tend to drive the spacecraft design more heavily than receive APAs.