A Compact Wideband Circular Polarization Antenna on the Purpose of Sub-6 GHz

A broadband circular polarization antenna with compact size for Sub-6 GHz is presented. The proposed antenna fed by co-planer waveguide (CPW) consists of asymmetric ground structure and modified circular-shaped radiator. Three slots are employed on the ground structure and the modified circular-shaped radiator, which is optimized to get a wide axial ratio (AR)-bandwidth. The inverted L-shaped metal-strip is designed to link with the ground, which is designed to excite two mutually orthogonal-modes with equal magnitudes to implement CP performance. By simulating and optimizing the dimensions of the antenna in the HFSS, the results show that a 43.3% (4.02-6.24 GHz) impedance bandwidth and 39.5% (3.85-5.75 GHz) CP bandwidth are achieved, respectively. Moreover, 2.58-3.8 dBi gain and stable radiating patterns are obtained within the operating frequencies.