Cavity-backed dual linear polarization sinuous antenna with integrated microstrip balun feed

In this work a low-profile cavity-backed dual linear polarized sinuous antenna with integrated baluns has been studied. The antenna was chosen to operate from 1.6 GHz to 7 GHz having an input impedance of 250 Ω with dual linear polarization. The sinuous antenna design guarantees a relaxed fabrication tolerance compared to the log-periodic sinuous antenna. The sinuous antenna is backed with a metallic cavity to achieve a unidirectional radiation pattern. Two linearly tapered microstrip baluns were designed to excite the antenna elements and placed horizontally parallel to the radiating elements to achieve a low profile.