Circularly polarised radial line slot array antenna for wireless LAN access point

The design of a planar circularly polarized (CP) Radial Line Slot Array (RLSA) for use as a 2.4 GHz WLAN access point (AP) antenna is presented. Computer simulated results for return loss (RL) are produced and compared with experimental results. Good agreement between simulations and experiment is noted. Other simulated and measured results concern the radiation pattern. Conical radiation pattern and circular polarization (3 dB axial ratio) over the required frequency band is achieved. Finally, a modification of this antenna to operate over a dual, 2.4 GHz and 5.2 GHz, frequency band is proposed and discussed.