Design of spiral slot-based dual-wideband dual-sense CP antenna

摘要

A dual-wideband dual-sense circularly polarised (CP) planar slot antenna with a simple structure is presented and studied in this study. By etching a simple spiral slot on the planar ground, adopting an L-shaped strip as the radiator, and employing smooth transition structure, the dual-wideband impedance bandwidths (IBWs) and dual-wideband 3dB axial-ratio bandwidths (ARBWs) of the proposed CP antenna can be easily realised. The measured 10dB return loss IBWs is 111.1% (0.88-3.08GHz) for the lower band [left-hand CP (LHCP)] and 42.1% (3.64-5.58GHz) for the upper band [right-hand CP (RHCP)]. The measured 3-dB ARBWs is 92.9 and 39.4%, with respect to 1.83GHz (LHCP) and 4.6GHz (RHCP), respectively. The radiation patterns of this antenna are good within both two CP bands. This antenna is very suitable for multi-band communication systems for its dual-wideband CP performance.