A 3D-SIW Circularly Polarized High Gain Horn Antenna for the Lower Sub-Terahertz Band

This work proposed a 3D circular polarized dielectric loaded substrate integrated waveguide (SIW) Hplane sectoral horn antenna. The antenna is an array of four laminated planar waveguides arranged as a square. Each element consists of two metal structures mounted on the top and bottom of a dielectric substrate with an array of metallic vias embedded in the substrate to emulate the vertical walls of a traditional waveguide. A dielectric slab identical to that of the horn and acting as a lens is used at the horn opening to increase the gain. The circular polarization is obtained by applying the sequential rotation technique. Otherwise, the antenna radiates linearly polarised electromagnetic fields with four equal beams (Mode M2 operation) when all elements are fed with the same amplitude and phase. The simulated results show that the antenna is wideband, has high gain, and has a high degree of polarization purity. These characteristics make it a good candidate for the 6 th generation of mobile communication systems (6 G) and monopulse radars.