Circularly Polarized Right Angle Slot Antennas for WLAN of IEEE 802.11b/g

In this paper, the design consideration for right-hand (clockwise) and left-hand (counterclockwise) circularly polarized microstrip slot antennas are presented. The circularly polarized antenna consists of two right angle slot antennas that is two orthogonal modes in phase quadrature or an array of linearly polarized slot with proper orientations and phases. This antenna can generate circular polarization by radiating orthogonal field components from two slots with equal amplitude but in phase quadrature. Two orientations for circularly polarized are investigated in this paper from simulation and measurement results are shown at resonance frequency 2.45 GHz on return loss, VSWR and radiation patterns.