Stacked dual-band electromagnetic band gap waveguide aperture with independent feeds

摘要

A dual-band stacked electromagnetic band gap (EBG) electronically scanned array (ESA) has a high-frequency aperture stacked on a low-frequency aperture. The high-frequency aperture looks through the low-frequency aperture. Low-frequency and high-frequency feeds feed the apertures. The low-frequency aperture comprises low-frequency cells with two vertical low-frequency EBG sidewalls and two horizontal metal walls. The high-frequency aperture comprises high-frequency cells with four cells stacked on each of the low-frequency cells. The four high-frequency cells comprise four vertical high-frequency EBG sidewalls, two horizontal metal top and bottom metal walls, and a center horizontal metal wall for operation with the same polarization as the low-frequency aperture. The high-frequency cells may comprise four horizontal high-frequency EBG sidewalls, two vertical left and right metal walls, and a center vertical metal wall for orthogonal polarization. A frequency selective surface may be used to provide isolation between the apertures.