New broadband L-shaped CPW-fed circularly polarized monopole antenna with asymmetric modified ground plane and a couple series-aligning inverted L-shaped strip

A new compact coplanar waveguide (CPW) -fed broadband circularly polarized (CP) monopole antenna is proposed in this study. The antenna structure is composed of an L-shaped monopole, an asymmetric modified ground plane and a couple series-aligning inverted L-shaped strip. The modification of cutting two slots in the asymmetric ground plane achieves a wide CP bandwidth, and a couple series-aligning inverted L-shaped strip is introduced with the left ground plane to achieve broadband impedance bandwidth (IBW). A −10 dB IBW of 103% (2–6.2 GHz) and 3 dB axial ratio bandwidth (ARBW) of 98% (1.9–5.85 GHz) is achieved. The antenna design process and the parametric study are presented, and the CP mechanism is analyzed.