Waveguide to microstrip transitions in W-band with LTCC technology

In this paper, two broadband rectangular waveguide to microstrip transitions at W-band with LTCC (low temperature co-fired ceramic) technology are proposed: WLWMT (WR-10 to LTCC waveguide to microstrip transition), and a novel probe transition of WR-10 to Microstrip using LTCC technology. To widen the bandwidth of WLWMT, two matching structures which are composed of stripline on different substrate layers connected by the staggered via side walls are buried. For the novel probe transition, inner conducting ground is used as waveguide backshort comparing with that in HIMCs (Hybrid Integrated Microwave Circuits). According to EM simulation, the WLWMT illustrates a 19% effective bandwidth (ranging from 91.6 to 98.2 GHz); the probe transition illustrates a 29% effective bandwidth (ranging from 90 to 100 GHz).