Wideband Single-Layer DC-Decoupled Substrate Integrated Waveguide (SIW) to Microstrip Transition Using an Interdigital Configuration

A transition from the substrate integrated waveguide (SIW) to the microstrip line with built-in dc-decoupling is presented. The proposed transition has an interdigital configuration on a single layer. It features a 25% relative bandwidth with less than 0.7 dB of insertion loss and more than 15 dB of return loss.