A novel design method on low cross polarization for dual‐polarized patch antennas

In this paper, a design method by a feed point perturbation is proposed to obtain a low cross polarization characteristic in dual-polarized patch antennas. In the present design method, the cross polarization generated by the mutual coupling between the orthogonal feed points is canceled by the cross polarization newly generated by the feed point perturbation. This design method is simple and does not require any special feed circuit. Hence, the method is effective for array antenna elements with a limited mounting area. Also, the optimum design conditions under the proposed design method are analytically derived. From the numerical results by the FDTD method and the experimental results, the effectiveness of the proposed design method and its optimum design condition is confirmed. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(9): 9–17, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10217