H-Plane Waveguide In-Phase Power Divider/Combiner With High Isolation Over the WR-3 Band
Jie Wang, Yun Zhao, Jiang‐Qiao Ding
Abstract
A novel <inline-formula> <tex-math notation="LaTeX">$H$ </tex-math></inline-formula>-plane waveguide in-phase power divider (also known as combiner) with high isolation working across full WR-3 band (220-330 GHz) is realized in this paper. This distinctive architecture is designed based on the sum-difference principle of Magic-T, whose <inline-formula> <tex-math notation="LaTeX">$E$ </tex-math></inline-formula>-plane branch (difference port) is matched with an <inline-formula> <tex-math notation="LaTeX">$E$ </tex-math></inline-formula>-plane T-junction. Both effects of processing and assembling uncertainties on this power divider/combiner performance are discussed in detail to display error sensitivity. The physical prototype is split into three blocks and processed by the state-of-the-art computer numerical control (CNC) milling technology. The absorbing materials are housed in the loaded T-junction arms to terminate return wave as well. Compared with the most reported terahertz waveguide power couplers, the meaningful measured results of this advanced in-phase power divider are delivered. The input and output matching as well as high isolation have been obtained over full WR-3 band, when an 11 dB reference level is considered. A total insertion loss of about 1.2 dB is achieved including three straight waveguides having a total length of 30 mm, which is also in good agreement with simulations. This module, which is fully compatible with the standard CNC-milling technique, can be directly integrated to terahertz detection systems.