Design of L/X-band shared aperture antenna array for SAR application

Design of a dual-wideband dual-polarized planar shared aperture microstrip antenna array is proposed in this article. Differential feeding method is used to enhance the isolation between polarizations of the antenna in both bands.Corporate feed network is used for good radiation pattern results. Further, the coupling between the feed networks the two orthogonal polarizations is minimized. This is achieved using the antenna elements to separate the feed networks for orthogonal polarizations. To verify the antenna design, a prototype is fabricated and measured. For VSWR, the antenna can cover from 1.07 to 1.24 GHz (14.7%) and from 8.3 to10.3 GHz (21.5%), respectively. The measured isolation between bands is higher than 30 dB and the isolation between polarizations is higher than 22.5 and 29.6 dB in L- and X-band, respectively.