Abstract: A transition from a waveguide to a microstrip, including a substrate having a plurality of ground surfaces superimposed on one another, the microstrip extending on the substrate and a plurality of through-contacts providing electrical connectivity to the plurality of ground surfaces. Wherein the waveguide includes a waveguide wall with an opening therein, the substrate projecting through the opening into the waveguide such that at least a portion of the microstrip is disposed within the waveguide, at least one of the plurality of ground surfaces being in contact with the waveguide wall.