Reconfigurable aperture decade bandwidth array

A variety of military systems employ multiple antenna apertures on a single platform such as a ship or an aircraft. In order to reduce cost and improve performance characteristics such as the radar cross section (RCS), it is desirable to combine multiple functions into a single aperture. Wide (10:1) bandwidth phased array antennas are needed to accomplish this goal. To satisfy multi-mission roles from a single aperture over a 10:1 bandwidth requires an array that can be quickly reconfigured to operate efficiently over sub-bands corresponding to the various application frequencies. Array reconfigurability includes the ability to select operating frequency bands for the radiating elements and reconfigure the aperture illumination function with electronic control of the feed network in order to create any required radiation pattern. The goal of this research is to develop and demonstrate a grating lobe free REConFigurable Aperture Decade Bandwidth phased ARray (RECAP DEAR) using control devices. Because of their small size and superior electrical characteristics, MEMS (microelectro-mechanical systems) switches are the device of choice. This paper addresses the array architecture and the design of a radiating aperture that may be reconfigured to provide a tunable phased array with an effective 10:1 operating frequency bandwidth. An array design based on a TEM horn with a switchable ground plane is used to illustrate the important concepts. We discuss a canonical array design to cover a 60/spl deg/ conical scan volume over the 2-20 GHz frequency band.