Multi-band phased array antennas for air-platforms

The increasingly global role of the USA military has put an added emphasis on high-data rate communication systems. In such applications, phased array antennas are preferred. This paper describes a new innovative phased array antenna technology which would reduce the size, the cost, simplify the design by lowering the RF losses in transmit and receive channels, extend the frequency coverage, and increase the functional capability of the phased array antennas. Since the beam scan of phased array antennas is limited to /spl plusmn/45 degrees at best, it is anticipated that six full capacity phased array antennas located on the spacecraft would provide the instantaneous communications with any ground station on the Earth and with the other airborne stations. The new wideband multi-functional phased array antenna design is capable of operating at either Ku-band or Ka-band without the need for switching or reconfiguration; and can be readily used to provide information in a timely manner to the various users. The design incorporates a number of novel ideas, including a low loss, extremely wideband phase shifter design, which uses a piezoelectric transducer (PET); a multi-frequency band diplexer system; and broadband high gain antenna radiating elements. Multiple antennas would need control and switching to be accomplished at a centralized location on the airplane.