60 GHz grounded-coplanar-waveguide-tosubstrate- integrated-waveguide transition for rof transmitters

A novel transition from a grounded-coplanar waveguide to a substrate integrated-waveguide (SIW) is presented featuring a fully planar bias tee for the development of 60 GHz radio-over-fibre photonic transmitters for indoor applications. The transition is intended to serve as a connection between a 60 GHz photodiode chip and SIW antennas suitable for indoor data distribution. Simulations show that in the whole 57-64 GHz communication band, the return loss (RL) is at least 15 dB, whereas the insertion loss (IL), is <; 0.9 dB. Measurements of a back-to-back configuration confirm the numerical results, with a IL of ~2 dB and a RL > 12 dB.