Quad-Port Circularly Polarized Ring Slot Multiple-Input Multiple- Output Antenna for 5G UWB Wireless Communication Systems

Abstract

A notable progress in antenna design, especially concerning multiple-input multiple-output (MIMO) antennas, is being driven by the emergence of 5G technology. One of the preliminary steps in constructing a multiple-input and multiple-output antenna involves choosing a suitable substrate material and thickness. The careful selection of dielectric substrate material and its thickness significantly influences the key characteristics such as physical dimensions, bandwidth, and radiation efficiency. This study presents the design and evaluation of a 4 Å~ 4 circularly polarized multiple-input and multiple-output antenna tailored for 5G applications, with focus on evaluating four dielectric substrates, Flame Retardant 4, RT/Duroid5880, RT/Duroid6002, and Rogers RO3003. All antennas were modeled and investigated through full-wave simulations using ANSYS High-Frequency Structure Simulator, with a uniform substrate thickness of 0.8 mm. Based on simulated results, RT/Duroid 6002 was selected for fabrication. The fabricated antenna operates in the range of 15 GHz–45 GHz, and achieves a wide measured bandwidth of approximately 13.5 GHz in this operating range. Measurements were conducted using a vector network analyzer and an anechoic chamber. The envelope correlation coefficient was found to be 0.001, indicating excellent diversity performance along with diversity gain and total active reflection coefficient. The study provides valuable insights into the direct effects of dielectric substrate properties on an antenna’s operation and guides substrate selection for the development of compact, wideband antenna arrays suitable for 5G mm-wave systems.

Cite this article as: A. Baliyan, M. G. Siddiqui, K. S. Kharb and A. Singh, “Quad-port circularly polarized ring slot multiple-input multiple-output antenna for 5G UWB wireless communication systems,” Electrica, 26, 0258, 2026. doi: 10.5152/electrica.2026.25258.