Wideband Aperture Coupled Line Feeding Microstrip Patch Antenna Design Using Different Shaped Patches

In this paper, a heptagonal shape microstrip patch antenna with aperture coupled microstrip line feeding technology is proposed to enhance the bandwidth. Two dielectric layers with same relative permeability is used among the three metallic layers: radiating patch on the top layer, ground plane with aperture coupling on the middle layer and line shaped feeding structure on the bottom layer. Roger RT/duroid 5880 (tm) with relative permittivity of 2.2 and dielectric loss tangent of 0.0009 is used as a substrate material. Firstly the circular patch and polygonal (i.e., pentagonal, hexagonal, heptagonal and octagonal) patches with aperture coupled are designed and compared to show the performances. Among them, the heptagonal shape patch gets the better performances. This antenna is resonated at 26.80 GHz with a bandwidth of 22.3% (23.46-29.46 GHz) and its return loss, gain, directivity and Voltage Standing Wave Ratio (VSWR) are -23.21 dB, 8.57 dB, 9.14 dB and 1.2 dB respectively.