Pinwheel-Shaped Polarizer for Generating Dual-Circularly Polarized Conical Radiation Patterns in the Ka-Band

In this contribution, the design of a 3D-printed dual-mode anisotropic dielectric polarizer is presented for millimeter-wave applications within the Ka-band (28-30 GHz). The dielectric polarizer, fed by a conical horn antenna, can convert the linearly polarized conical radiation patterns obtained when exciting TE01 and TM
01
modes into right-handed circularly polarized (RHCP) and left-handed circularly polarized (LHCP) conical radiation patterns, respectively. The horn antenna is fed by a mode-converter with two input ports and one output port. When TE10 mode is excited at input port 1, TE01 mode is radiated by the horn, and the polarizer converts the phi-polarized wave into a RHCP wave. Conversely, when TE10 is excited at input port 2, TM
01
mode is radiated by the horn, and the polarizer converts the linearly theta- polarized wave into a LHCP wave. Simulated results show an axial ratio (AR) below 2 dB across the entire frequency range for dualmode operation.