Directional coupler includes a first, second and third transmission lines. Each of the first and second transmission line elements is disposed on a dielectric substrate, and has a first end and a second end. At least a portion of the first and second transmission line elements are adjacent along a path. A third transmission line element is disposed along the path between the first and the second transmission line elements and separated therefrom by a portion of the dielectric substrate. The third transmission line element is electrically connected to a ground plane disposed on a surface of the dielectric substrate opposed from the first and second transmission line elements.