A 2–6 GHz Dual-Polarized PUMA Array with An Improved Structure

A dual-polarized PUMA array operating at 2-6 GHz is presented. To overcome the PCB stackup problem caused by the lower frequency band compared with previous designs, an improved PUMA structure is designed, in which part of dielectric is replaced by air substrate. The array achieves active VSWRs of less than 3.1 and 4.1 in E- and H-planes for all scanning angles to 45°, respectively. The thickness of the array is approximately 0.29 wavelength for 6 GHz (excluding aluminum ground plane). An $8 \times 8$ prototype array containing active T/R modules was fabricated and measured to verify the PUMA design. The measured results of VSWRs and scanning patterns verify the design principle.