A Compact Multiband Microstrip Antenna with Metamaterial Loading for Simultaneous Band Control and Gain Enhancement in 5G IoT Systems

A small multiband microstrip antenna loaded with metamaterial elements is proposed in this paper for band control and gain improvement for 5G IoT applications. The antenna is based on a planar microstrip structure with split ring resonators. The metamaterial loading alters the effective permittivity and permeability and creates additional resonances. This allows for the controlled design of multiple bands in the sub-6 GHz frequency range. The antenna is designed using an FR4 substrate with a compact structure. The proposed design shows that the reflection coefficient values are found to be below −10 dB at 2.45 GHz, 3.50 GHz, 5.20 GHz, and 6.70 GHz at the operating bands, and the VSWR is less than 2 at these frequency bands. The gain is improved because of the use of metamaterials. The radiation pattern is consistent at various frequencies. The design is free of complex structures and additional components. It is shown that the antenna is suitable for multiband 5G and IoT applications.