High-frequency transmission line connection structure, circuit board, high-frequency module, and radar device

摘要

The invention relates to a high-frequency transmission line connection structure, a circuit board having the connection structure, a high-frequency module having the circuit board, and a radar apparatus. A first laminated waveguide sub-line part (21) includes a pair of main conductor layers that oppose each other in a thickness direction with a dielectric layer (31) having the same thickness as a dielectric layer (31) of a microstrip line (1) interposed therebetween. A second laminated waveguide sub-line part (22) includes dielectric layers (31, 32) thicker than the dielectric layer of the first laminated waveguide sub-line part (21). A laminated waveguide main-line part (23) includes dielectric layers (31, 32, 33) thicker than the dielectric layers of the second laminated waveguide sub-line part (22). A conversion part (10) connected to the microstrip line (1) is formed by integrating with an upper main conductor layer constituting the respective line parts.