Circularly polarized array antenna with conical beam radiation

A 2 × 2 array antenna with conical beam radiation is proposed. To achieve circular polarization (CP) with broad axial ratio (AR) bandwidth that can cover the WLAN 2.4 GHz band, each array patch element is loaded with a near semi-circular slot fed by an L-shaped probe, which is linked to a corporate feed network. Here, the conical beam radiation with a peak gain at 30 degrees theta (θ) angle is achieved simply by arranging the 4 array patches in a sequentially rotated fashion.