P-L band Planar Ultra-Wideband Modular Antenna (PUMA) Arrays

Because of the large physical element size, there is significant difficulty in manufacturing of the planar ultrawideband modular antenna (PUMA) array operating in the P-L band. To solve this problem, a new PUMA element without capacitive coupling patches or capacitive through-vias is presented. The printed dipole in the PUMA element is asymmetric, and is fed through a vertical strip-line balun. Consequently, the designed PUMA element achieves ±45° scanning both in the E and H planes within a bandwidth of 6.5:1 in the P-L band. The sizes of the element are
$50 \times 50\text{mm}(0.43 \lambda_{\mathrm{h}}, \lambda_{\mathrm{h}}$
is the free-space wavelength at the highest operating frequency), and the total profile is 76.5mm (
$0.66 \lambda_{\mathrm{h}}$
). The simulation results of an infinite array show that the proposed element can scan up to ±45° in the E and H planes within 0.4–2.6GHz with orthogonal port isolation better than 10dB. The design is verified by measured results of an
$8 \times 7$
array antenna prototype.