A waveguide assembly for propagating electromagnetic signals includes first and second dielectric waveguides and a shield. Each of the first and second dielectric waveguides includes a cladding formed of a first dielectric material. The cladding defines a core region therethrough that is filled with a second dielectric material different than the first dielectric material. The shield is disposed between the first dielectric waveguide and the second dielectric waveguide. The shield is electrically conductive. The shield does not surround an entire perimeter of either of the first dielectric waveguide or the second dielectric waveguide.