A Broadband Forward-Wave Directional Coupler Using Periodic Y-Shaped Ground Via Structures With Arbitrary Coupling Levels

@article{Yen2013ABF,
  title={A Broadband Forward-Wave Directional Coupler Using Periodic Y-Shaped Ground Via Structures With Arbitrary Coupling Levels},
  author={J. Yen and Sen-Kuei Hsu and Tong-Hong Lin and Tzong-Lin Wu},
  journal={IEEE Transactions on Microwave Theory and Techniques},
  year={2013},
  volume={61},
  pages={38-47}
}
A broadband forward-wave directional coupler loaded with periodic Y-shaped ground via structures is proposed. Broadband impedance matching of the even and odd modes can be approximately achieved. The proposed coupler can provide an almost constant phase difference between the even and odd modes over a wide frequency range. Therefore, a forward coupler with broad bandwidth can be expected. Based on the Bloch-Floquet theorem, the Bloch impedances and the electrical lengths of both modes can be… CONTINUE READING