SIW Cavity Backed High-Gain Slot Antenna using Metamaterial for 5G mmWave Communications

This paper proposes a low-profile high-gain SIW-cavity backed slot antenna using metamaterial slab in the superstrate of the reference antenna for 5G mmWave communications. The proposed antenna operates at the frequency band of 27.7 - 29.2 GHz with realized gain greater than 9.8 dBi throughout the entire operating frequency band whereas the reference antenna gain is 4.6 dBi and the antenna profile is 0.2 λ
0
at the frequency of 28 GHz. The superstrate slab is working as a low-impedance metamaterial and the front-to-back ratio is improved by 5.2 dB at 28 GHz due to the application of the metamaterial. The radiation efficiency of the proposed antenna is greater than 92 % throughout the entire operating frequency band of the antenna. This low-profile high-gain antenna can be used in mmWave communications.