Ring-Shaped <i>D</i>-Band <i>E</i>-Plane Filtering Coupler
Xun Chen, Yi Wang, Qingfeng Zhang
Abstract
This letter presents a ring-shaped E-plane filtering coupler working at 150 GHz with high performance. The coupler is based on cavity resonators. Unlike the conventional ones, the four resonators in this coupler are all bent along their length direction and connected end to end, forming a closed circle. By adjusting the radius of the circle, three of the resonators work on TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">101</sub> mode while the other is on TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">102</sub> mode. The coupler can be split through E-plane and the measured response of the coupler has an excellent agreement with the simulation, with a low amplitude imbalance of 0.31 dB, insertion loss of 0.12-0.46 dB, and over 20-dB return loss and isolation.