Broadband half-mode substrate integrated waveguide (HMSIW) Wilkinson power divider

A broadband H-plane Wilkinson power divider that makes use of the half-mode substrate integrated waveguide (HMSIW) technique is presented in this work for the first time. This broadband power divider utilizes the half-mode structure of SIWs such that the overall size is largely reduced at least by half. In addition, the lossy network or resistor branch is integrated with the SIW structure in order to obtain good output matching and isolation if unbalanced signals are combined or divided. The proposed concept is then validated by theoretical analysis and measurements. Good input return loss (S₁₁) and insertion loss (S₂₁, S₃₁) performances are obtained theoretically and experimentally across a very broad bandwidth from 18 GHz up to 40 GHz. In the meanwhile, output return loss (S₂₂, S₃₃) and isolation (S₂₃) better than -10 dB are also ensured across a 64% bandwidth from 18 GHz to 35 GHz.