3-D-Printed Compact Wideband Magnetoelectric Dipoles With Circular Polarization

A three-dimensional (3-D)-printed compact unidirectional wideband antenna, based on two crossed magnetoelectric dipoles, is proposed in this letter. The antenna consists in folding the electrical dipole elements; thus, the surface of the radiation element is reduced to 0.23λ0 × 0.23λ0, where λ0 is the wavelength at the lowest operation frequency for a standing-wave ratio (SWR) <;2.5, corresponding to a reduction factor of 48%. Despite a complex 3-D structure, each dipole arm is prototyped using 3-D printing technology. The excellent agreement between measured and simulated results (impedance and radiation) demonstrates the quality of such realization process for low-cost prototyping of such antenna structure. In dual-polarization mode, the measured input impedance bandwidth is 57% from 1.67 to 2.94 GHz with an SWR <;2.5. Circular-polarization mode is obtained by connecting a 90° hybrid coupler circuit. Axial ratio is lower than 3 dB in measured and simulated results from 1.5 to 3 GHz.