LTCC-Integrated $H$ -Plane Bends for THz Antenna-in-Package Solution

We present a compact terahertz antenna-in-package solution using a substrate integrated waveguide (SIW), which connects an integrated circuit (IC) to an SIW antenna. To suppress the leakage of electromagnetic waves due to bending a low-temperature cofired ceramic (LTCC) substrate, an H-plane bend SIW in the LTCC was investigated using the E-plane split-block technology. We introduced an IC with a CPW-to-waveguide transition into the hollow SIW. The insertion loss, estimated by measuring a back-to-back transition with the H-plane-bend SIW, is 1.6 dB at 300 GHz, and 49-GHz bandwidth with less than 10-dB return loss is achieved.