3D Printed Broadside Coupled H-guide Based Directional Coupler at Sub-THz Frequency

In this paper, we designed and analysed the broadside coupled H guide based directional coupler for the Sub-THz frequency range. The designed broadside directional coupler is fabricated using the Form Lab SLA (stereolithography) based 3D printer. In this technique, Grey resin material is used which acts as a polymer material. To excite the LSM mode firstly we designed the broadband transition from rectangular waveguide to H-guide which is fed by the rectangular waveguide WR-2.8. The even and odd mode properties of the broadside coupled H-guide have been studied. The proposed broadside coupler has a 24dB coupling at a frequency of 330GHz. To enhance the mechanical stability we introduced the bridge between the broadside coupled guides. In addition to the bridge and altering the gap between the waveguide, the coupling is varied with respect to the frequency.