Millimetrewave groove guide with V-shaped grooves

The use of a V-groove guide has been investigated and compared with rectangular-groove guide. The V-groove guide is found to be superior. It has lower attenuation and rejects higher-order modes more effectively. Connection losses are small, and guide losses are around 0.4 dB/m at 96 GHz for an aluminium machined guide even with intermediate connections. For a 90° V-groove of depth equal to 0.4 of the plane separation, the guide wavelength is about 1% larger than the free-space wavelength. It is expected that the V-groove guide will provide a valuable single-mode low-loss and wideband waveguide for millimetrewave propagation.