X-Shaped Circularly Polarized Aperture Coupled Antenna for WLAN

This paper presents a new compact aperture-coupled circularly polarized (CP) antenna for WLAN applications. The new designed antenna consists of X-shaped slot rotated by 45° with unequal arms etched on a circular microstrip antenna fed through the coupling between the ring slot and the microstrip line. The circular polarization is obtained due to the unequal X-shaped slot arms. The antenna with overall size of 60 × 60 × 5.83 mm has a 10 dB impedance bandwidth of 30% (4.8-6.5 GHz), a 3 dB AR bandwidth of 3.47% (5.67-5.87 GHz) and 3-dB gain bandwidth of 46.62% (4.08-6.56 GHz) with a peak gain of 8.85 dBi.