Magic Tee Junction Based on Hybrid Architecture of Microstrip Line and Non-Radiative Dielectric Waveguide

A new magic tee junction based on hybrid planar/non-radiative dielectric (NRD) guide integrated circuit technology is presented. Two separate junctions are used to form this magic tee junction. The first is an NRD T-junction optimized for LSM10 mode to LSE10 mode conversion. This junction has the similar properties as an E-plane rectangular waveguide T-junction. The second is a microstrip line junction that feeds two microstrip-to-NRD LSE10 mode transitions in transferring the signal to the two output branches of the NRD T-junction. This hybrid geometry has the properties of a H-plane waveguide T-junction. Measured results show that an isolation of 20dB can easily be achieved between the sum and difference ports.