A 7-21 GHz Dual-Polarized Planar Ultrawideband Modular Antenna (PUMA) Array

The design, fabrication, and measurement of a 16 x 16 dual-polarized planar ultrawideband modular antenna (PUMA) array operating over 7-21 GHz (3: 1 bandwidth) are presented. The array is comprised of tightly coupled dipoles printed on a grounded dielectric substrate and are excited by an unbalanced feeding scheme that eliminates external wideband baluns and feed organizers. The array can be assembled modularly, where each low-profile, fully planar, low-cost tile is fabricated using standard multilayer microwave PCB techniques. A unique solderless, modular interconnect mates the array to a dilation fixture that facilitates measurements using standard surface-mount assembly (SMA) connectors and terminations. After presenting the most critical design trends, simulation results of the final array in infinite, infinite x finite, and finite x finite models are compared with measurements. This prototype array exhibits a measured active VSWR < 2.1 and close to ideal gain at broadside, and VSWR < 2.8 with low cross-polarization out to theta = 45 degrees in all planes, showing close agreement with simulations.