High-Gain Dual-Polarized Dual-Beam Planar 1-Bit Cassegrain Antenna

A dual-linearly-polarized dual-beam planar 1-bit Cassegrain antenna operating at 28GHz is proposed and experimentally verified. Different from conventional Cassegrain antenna, the proposed antenna consists of a hyperboloidal subrefletor and a main reflector made of reflectarray, fed by a dual-linearly polarized ridged-horn antenna. In addition, the reflectarray is constructed by an array of 1-bit dual-pol microstrip patch elements to prepare for dual-polarized scanning applications. In the evaluation, two beams are realized, one at $\theta=$ 30° in one polarization and one at $\theta=0^{\circ}$ in the other polarization as a desired, each with a gain of 24dBi and 23.2dBi respectively, both with side lobe levels below $-10 \mathrm{~dB}$. The measured results agree well with the simulated ones. The successful realization of the proposed antenna and the measured results pave the way for further design of planar Cassegrain antenna with dual-pol beamscanning capability.