UWB cross-polarization discrimination with differentially fed, mirrored antenna elements

The paper describes a principle of broadband discrimination of cross-polarization in linearly polarized radiators. The cross-polarization suppression is achieved by the application of two differentially fed mirrored antenna elements. It is shown, that in such configuration the cross-polarized components radiated from both elements are out-of-phase and annihilate each other, whereas the co-polarization components are in-phase and interfere constructively in the far field of the radiator. For the verification of the idea the prototype of the single antenna with strong cross-polarized components is designed. Next an array comprising differentially fed, mirrored antenna elements is presented. The measurements show a significant reduction of the undesired cross polarization radiated from the antenna and simultaneous enhancement of co-polarization. The idea presented in this paper can be successfully applied in the design of UWB dual-polarized antennas.