This spiral antenna approach utilizes a conducting backplane within a PCB stackup to eliminate the need for a separate cavity backing structure. The spiral antenna is enclosed within a PCB via cavity to prevent mutual coupling from adjacent elements in an array environment. Resistive material is embedded within the PCB stackup on the conducting backplane layer to suppress undesired modes generated by the cavity geometry.The spiral antenna design is a differential fed, dual arm , Archimedean spiral antenna. This design produces circular polarization over a wide beamwidth and bandwidth. The arms of the Archemedean spiral are end-loaded with resistive material or surface mount chip resistors. The size of the antenna is small to allow integration into a wide-band array. The PCB design allows for highly integrated, inexpensive, automated manufacturing solution over a wide frequency band by allowing the feedlines and/or other RF/Microwave components to be co-located directly behind the antenna aperture. To our knowledge no other antenna approach has all of these inventive features. Most antennas in this category require a separate cavity to provide unidirectional radiation.