A Ka-Band Waveguide Magic Tee with Full Bandwidth and Low Imbalance

A Ka-band magic-tee with four arms transition is presented in this paper. A proposed metal cone and a cylinder matching structure are implemented in the center of the waveguide junction, resulting in both good amplitude and phase balance over the full bandwidth from 26.5 GHz to 40 GHz. The presented magic tee exhibits enhanced fabricability, and assemblability for waveguide systems. Excellent agreement between the simulation and measurement results was achieved. The measured in-band insertion loss was less than 0.3 dB with a maximum amplitude imbalance of 0.1 dB and a maximum phase imbalance of 2°. In addition, the return loss is at least -10 dB smaller for all ports and the isolation is more than 26 dB between the opposite ports.