A Ka-band self-packaged transition from groove gap waveguide to CBCPW using PCB supersede metal lid

This article introduces a novel transition that utilizes a printed circuit board (PCB) to replace the traditional metal lid of the groove gap waveguide (GGW). An efficient conversion from the GGW to the reflection cavity, consisting of a plated-blind groove and a shorting back, is achieved using the wedge. The tapered wide-slot probe is positioned at the bottom of the PCB to couple the electric field and simultaneously convert the TE $ _{10} $ 10 mode in the GGW to the quasi-TEM mode in the conductor-backed coplanar waveguide. The operational mechanism of the transition is investigated, the design procedure with good operability is proposed, and the key dimensions are analyzed. Additionally, a back-to-back transition prototype is developed and experimentally investigated. The prototype demonstrates an insertion loss of less than 2.05 dB in the Ka-band and a 50.5% 10-dB return loss fractional bandwidth. It should give prominence that the configuration of the transition offers a dedicated layer for peripheral circuit placement. This unique advantage can address the inconvenience of integrating peripheral circuits with the GGW and provide a viable solution to applying the GGW in more complex radio frequency modules or systems.