Bandwidth and Gain Enhancement of an Aperture Antenna With Modified Ring Patch

In this letter, a linear-polarized ring aperture-coupled antenna with single modified ring patch is presented. In our proposed design, the patch is applied to improve the bandwidth and gain, simultaneously. In addition, the designed feed-line shape also has a considerable effect on the bandwidth. The simulation results show that matching bandwidth with a VSWR lower than 1.5 and 1-dB gain ripple bandwidth is 34% and 42%, respectively. The peak gain of 9.2 dB and radiation efficiency above 96% over the bandwidth are achieved. There is a good agreement between simulation and measurement results. An adequate cross polarization can be obtained in the E-plane and H-plane.