A 2×4 circularly polarized antenna Array for WLAN applications

In this paper, a compact 2.45GHz circularly polarized (CP) antenna and a 2×4 antenna array are designed and fabricated. The CP characteristic is achieved using the unbalanced slots on the circular patch which subsequently makes the antenna compact. A 2×4 antenna array is designed using sequential rotation feeding scheme with a simulated axial ratio (AR) of more than 95MHz and gain of 12.5dBi. The measured return loss for the antenna element is greater than 20dB with a minimum axial ratio (AR) of 0.21dB. The measured return loss for the 2×4 array is greater than 15dB and the measured minimum axial ratio is 0.195dB with a 3dB AR bandwidth of 48MHz.