K/Ka Dual-Band Dual-Polarized Shared-Aperture CTS Array With High Isolation

A dual-band dual-polarization (DBDP) shared-aperture continuous transverse stub (CTS) array operating at K- and Ka-band with high isolation is proposed in this paper. The shared-aperture antenna array consists of a 6-element CTS array and two linear source generators (LSGs) based on parabolic reflectors. Two LSGs, placed at both ends of the CTS array, are designed to excite the transverse electromagnetic (TEM) and the first transverse electric (TE 1 ) modes of the parallel plate waveguide (PPW). These two orthogonal modes operate at K- and Ka-bands, respectively. To improve the port isolations, the geometrical sizes of two LSG meet the single-mode transmission conditions of the rectangular waveguide and the TE 1 mode transmission conditions. At the center frequencies of 19.7 and 28 GHz, the simulated port isolations are greater than 70 and 60 dB, respectively. The maximum gains for the two bands are 22.4 and 24.2 dBi.