Improvement of bandwidth in microstrip antennas using parasitic patch

The improvement in bandwidth when a parasitic element is used along with the short circuit patch has been theoretically analyzed and practically observed. The quarter wave microstrip element is designed for operation at 1.6 GHz with a substrate of dielectric constant 4.8 and thickness 1.6 mm. The bandwidth of the short circuit patch with a 1-m*1-m ground plane mount is 55 MHz; the measured value of the center frequency is 1.587 GHz; the beam width is 86 degrees and its gain is 11.5 dB. The bandwidth of the short circuit patch with the parasitic element with a 1-m*1-m ground plane mount was 204 MHz, and the center frequency was measured as 1.47 GHz, with a beam width of 78 degrees and a gain of 11.6 dB.<>