Four-port MIMO Vivaldi antenna for access points

Autores: Lilian Redonda‐Cuadra, José Alfredo Tirado‐Méndez, Hildeberto Jardón‐Aguilar, Rubén Flores‐Leal, Arturo Rangel‐Merino, Jaime Abarca Reyna, Luis Alberto Vasques‐Toledo

Resumen:
In this article, a 4-port multiple input, multiple output (MIMO) antenna array is presented, based on a Vivaldi design for nonplanar applications like access points above 6 GHz. The antenna is configured with four Vivaldi antennas arranged orthogonally, one to each other, to increase the electromagnetic isolation among elements. The Vivaldi element is fed with a microstrip with an integrated balun in only one arm, and each arm is set in an antipodal position to the other, giving an easy-to-design and build prototype, with no complicated feeding techniques. Each antenna plane has dimensions of 90 × 40 mm². The array presents a bandwidth from 5.3 GHz to beyond 20 GHz, with electromagnetic isolation above 20 dB, an envelope correlation coefficient below 0.001 for the entire bandwidth, giving a diversity gain around 20 dB, and a total active reflection coefficient below −10 dB from 7 to 20 dB, fulfilling the metrics for MIMO applications.

Revista: Microwave and Optical Technology Letters

https://doi.org/10.1002/mop.34018