Optimising the coaxial‐fed location to enhance circular polarization bandwidth of stacked microstrip antennas

A new technique is developed to best locate the coaxial feed of a circularly polarized stacked microstrip antenna with the objective of improving the axial-ratio bandwidth and CP quality of the antenna. In the proposed technique, we move the single feed on an arc between the diagonal and main axis of the driven patch to optimize CP performance. An antenna, on the basis of this technique, has been designed using the Microwave Studio software, and a prototype has been fabricated and tested. The antenna measurements show an excellent 14.8% AR bandwidth, 8 dB gain (over the impedance bandwidth), and 19.5% impedance bandwidth. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 132–135, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22096