A loop-type end-launcher for carbon fiber reinforced polymer waveguides

The analysis of an end-launcher type transition from coaxial to WR90 waveguides is presented. This transition is tuned to have the highest performance at the radar frequency of 9.375 GHz. The characteristics of the transducer are investigated comparatively in 30 cm aluminum and carbon ¯ber reinforced polymer waveguides. The advantage of the proposed feed is that it does not require grounding to the broad wall of the waveguide compared to the traditional end- launcher loop feeds. This departure from the current loop feeds makes the proposed feed suitable for carbon ¯ber reinforced polymer waveguides where a disruption in the broad wall would be undesirable.