A Planar Dual Polarized Shared-Aperture Array for K-/Ka-band Satcom Application

This paper presents a planar shared-aperture array antenna with dual linear and dual circular polarization for K-/Ka-band Satcom applications. K-band horizontally polarized waves are generated by substrate integrated coaxial line (SICL)-fed transverse slots, whereas Ka-band vertically polarized waves are formed by a substrate integrated waveguide (SIW)-fed slot pair. In addition, the circularly polarized solution is also provided in this paper to meet the requirements of some Satcom applications. Two independent rotated dipoles are placed above the horizontally polarized K-band and vertically polarized Ka-band elements, resulting in dual circularly polarized waves. Since the K-band and Ka-band elements share the same metal fence, the proposed arrays can obtain high channel isolation and high aperture usage efficiency in the linear and circular polarization states. Furthermore, the channel isolations in both bands can be also improved by introducing the high-pass characteristic of SIW. The outstanding isolations in both frequency bands demonstrate that the proposed antennas can be adopted for the Satcom system.