MPRWG-to-DiRWG transition with fitted PCB substrate inset

A design of metal-pipe rectangular waveguide (MpRWG) to dielectric-inserted rectangular waveguide (DiRWG) for 8-12 GHz is proposed. The transition includes an air-filled WR-90 metal waveguide with tapered waveguide dielectric that is fabricated using simple machining and Printed Circuit Board (PCB) process. The transition and dielectric taper, fabricated from PCB substrate is contained within the overall structure of the module to secure the effective transition and reduce radiation loss. Measured results of the transition shows excellent performance with the bandwidth of 33 %, return loss better than 8 dB and insertion loss below 2 dB. This transition and manufactured prototype has huge potential for conceptual and feasability study on low-frequency optical system and millimeter-wave component development.