A simple and compact broadband circularly polarized circular slot antenna for WLAN/WiMAX/DBS applications

Abstract

Abstract A simple and compact circularly polarized broadband circular slot antenna is proposed for WLAN/WiMAX/DBS applications. The main objective of this work is to design a microstrip line fed broadband circularly polarized antenna that is achieved by introducing an asymmetric perturbation over the circular slot onto the ground plane. A broad axial ratio bandwidth is achieved by using a small circular segment cut into the circular slotted ground and by adding a short stub on the feedline. To achieve a broad impedance bandwidth, a horizontal strip onto the slotted ground is placed just above the feed line on the opposite side. The proposed antenna is fabricated with an overall dimension of 20 × 20 × 1.6 mm3 (0.34λ o × 0.34λ o × 0.03λ o, where λ o represents the free-space wavelength at the center operating frequency). It is found that the impedance bandwidth of 75.82% ranges from 3.21 to 7.13 GHz and the 3 dB axial ratio (AR) bandwidth reaches 54.27% from 3.8 to 6.6 GHz. Throughout this paper, the improvement and validation process of the proposed antenna outcomes to accomplish desired characteristics are discussed.