Low-cost, planar and wideband phased array with integrated balun and matching network for wide-angle scanning

In this paper, we expand the current sheet array (CSA) concepts, proposed by Munk et al. to design, fabricate and measure a wideband phased array with an integrated conformal balun. A unique feature of the proposed array and feed is its low-profile planar layered PCB construction. Specifically, a single microwave laminate is used for the array aperture and another (underneath) supports all associated baluns and matching networks. As an example, a X-band 2166 element array with feeds is printed on two sheets of standard (12 x 18 in²) PCB, with minimal material, processing and assembly costs.