Published in Baek, S. H., Lee, B., & Harackiewicz, F. J. (2007). Modified aperture coupling annular-ring antenna fed by stripline. Antennas and Propagation International Symposium, 2007 IEEE, 3680 - 3683. doi: 10.1109/APS.2007.4396337 ©2007 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.


Various types of feed structures for microstrip antennas are compared. Broad bandwidth is obtained using aperture coupling with impedance matching. One of advantages in aperture coupling is polarization purity. A modified aperture coupling annular-ring antenna fed by microstrip is presented in this paper. This antenna structure can be considered as the combination of aperture feeding and proximity feeding an annular-ring antenna. It has both advantages in the polarization purity and in reduction of back radiation. From the structure based on the proximity feed annular-ring antenna, an aperture layer is inserted and modified as well as an aperture size to enhance bandwidth.