Abstract: A Guanella 1:4 balun is made capable of handling frequencies in the gigahertz range by printing its transmission lines on a microwave laminate. The resulting balun has a largest dimension substantially smaller than one free space wavelength throughout a 20:1 usable frequency range.

Abstract: A conductor-backed coplanar waveguide traveling wave antenna including a dielectric substrate, a coplanar waveguide structure disposed on the substrate, a plate separated from the substrate for concentrating energy radiated by the antenna generally in a half-space adjacent the exterior of the coplanar waveguide structure, and a feed electrically coupled to the coplanar waveguide for transmitting electromagnetic energy to and from the antenna. Preferably, the plate includes a conductive surface facing the substrate. The aforementioned substrate and plate are separated by a structure which has electromagnetic wave absorbing properties. This antenna is flush-mountable because the separation between the plate and substrate can be made very small, and has broadband capabilities due to its traveling wave producing structure.