Miniaturized 3D Multi-Segment Wire Antenna for 5G

The development of 3-D miniature segmented monopole antennas is presented. Each segment is oriented randomly in space to reduce the volume occupied by the antenna while obtaining good characteristics: compactness, efficiency, impedance matching, and bandwidth. Its small size and broad bandwidth make it suitable for 5G systems. Because of the absence of any dielectric losses, a segmented wire antenna is a good alternative to planar antennas in particular when very high efficiency is required. A multi-objective genetic algorithm has been implemented to optimize the design. A 7-segments antenna that occupies a volume of A0/4.81 ×. A0/6.10 × A0/7.03, where A0 is the wavelength at 3.28 GHz, was obtained. Its impedance is fairly close to 50 ohms in all bandwidth (3.28-3.61) GHz, and the reflection coefficient is better than −12 dB. The radiation efficiency is higher than 95% for the entire C-band (3500–3600 GHz), and the polarization of the antenna is linear.