A Ka-Band Duplex Ceramic High-Temperature Resistant Dielectric Rod Antenna

In this paper, a Ka-band duplex dual-polarized high-temperature resistant dielectric rod antenna (DRA) is designed with high isolation. The pyramidal tapered DRA fed by waveguide is packaged by thermal protection shield and thermal insulation material. The rectangular microstrip patch antenna (MPA) connects with the other end of the waveguide. The waveguide is directly soldered to the dielectric substrate so that the vias virtually lengthen the waveguide into the dielectric substrate and suppress the propagation of surface waves. Duplex dual polarization is realized by first two modes TM10 and TM01, which are excited by orthogonal microstrip slot coupling. The center frequencies of two channels can be determined by the length and width of the rectangular patch. The isolation can be improved by bending at the open end of the microstrip feed lines. Due to the lower thermal conductivity of ceramic dielectric of DRA and longer gap between feed port and the top of thermal insulation material, the feed port temperature is kept below 135 ℃ for 2000s under the continuous temperature of 1200 ℃.