The Design of 180∼260 GHz Turnstile OMT for Communicate Application

Orthomode transducer (OMT) plays an important role in modern communication system. In this paper, we present a terahertz wave turnstile OMT in the 180~260GHz band. The OMT has a circular waveguide common port and two standard rectangular waveguide ports (WR-4.3). This design consists of three parts--a turnstile junction, two power dividers and three kinds of waveguide bends. Over the whole frequency band, the reflection coefficient of each port is less than -20 dB, the insertion loss is less than -0.05 dB, with the isolation of orthogonal polarized wave being better than -55dB.