Substrate Integrated Waveguide Integration Platform for 60 GHz Indoor Photonic Transmitter

We present a novel integration platform for 60 GHz Radio-over-Fiber (RoF) photonic transmitters based on RF laminates. The platform is designed to allow the connection of a high-frequency photodiode (PD) chip, whose coplanar waveguide (CPW) output is wire-bonded to a grounded coplanar waveguide (GCPW) created on the laminate, to an H-plane substrate integrated waveguide (SIW) horn antenna. A DC-decoupled GCPW-to-SIW transition, featuring a fully planar bias tee, is used to efficiently bias the PD and to deliver the generated 60 GHz signal to the antenna. Simulations show that in the whole 57-64 GHz band the return loss (RL) of the platform (transition and antenna) is at least 6.5 dB, while the RF-to-DC isolation (IS) is higher than 27 dB. Measurements confirm a RL of at least 4 dB in the whole operating band and the desired sectorial radiation properties of the antenna.