$H$ -Plane Narrow-Wall Double-Ridge Waveguide Coupler in $V$ - and $W$ -Bands

A design of a double-ridge waveguide narrow-wall multiple-aperture coupler suitable for conventional machining is demonstrated. Different options for coupling levels up to 3 dB, all working over V-band (45-75 GHz) and W-band (75-110 GHz), are given. The narrow-wall coupler is designed in a custom-made transmission line, double-ridge waveguide, denoted by WRD45110. To experimentally validate the proposed design method and the performance of a selected component, a 15 ± 3 dB narrow-wall coupler is fabricated using computer numerical control machining in three individual pieces; the top section, the middle wall, and the bottom section. Two different H-plane cut assembly techniques utilizing male-female parts and pin walls are examined. The obtained results show a good agreement between simulations and measurements for both methods, therefore proving these components are now feasible.