Design of a waveguide two-plane coupler with a different division ratio in horizontal and vertical directions

This manuscript releases a novel two-plane coupler with a different division ratio in the horizontal and vertical directions working from 27.65GHz to 28.85GHz, with 4.1% fractional bandwidth. Compared with a previous two-plane coupler, this new division distribution is based on advanced and comprehensive cognition of the mechanism for the waveguide modes inside the coupled region. By tuning the phase difference brought by TE20-1ike mode and TM11-like mode in the quarter section, the final output can realize the designated division ratio in the horizontal and vertical directions.