A compact 1-to-4 broadband planar multi-section Wilkinson power divider

A compact 1-to-4 broadband WPD is presented. By combining multi-section impedance transformation and the even-odd mode analysis of
$2^{n}$
symmetric circuits, the WPD has ultra-bandwidth reflection and isolation. A detailed design procedure is elaborated to determine the impedance. A WPD is designed, simulated and fabricated in
$f_{0}=10$
GHz and satisfactory agreement between simulated and measured results demonstrate the feasibility of proposed approach. The measured results show 91 % bandwidth with more than 13 dB in-band isolation and return loss at all output ports.