$90^{\circ} \mathrm{H}$-Plane Transition Design from Standard Waveguide to Half-Mode Groove Gap Waveguide in E-Band

A transition design between standard waveguide to half-mode groove gap waveguide (HM-GGW) is presented that connects the HM-GGW through a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$90^{\circ} \mathrm{H}$</tex>-plane bend to conventional waveguides in E-band through a matching bar on one side, and an edge chamfer on the other side. The HM-GGW unit cell consists of a half waveguide placed on top of a magnetic wall realized by equally spaced rectangular pins to achieve a propagating half-mode. The waveguide concept is inspired by the typically used matching post of waveguide transitions. The concept is validated through simulations and measurements in the E-band, demonstrating a wide operational frequency bandwidth with a -20 dB input reflection coefficient over 14 % of the band.