Dual-band Split-ring Antenna with High-gain Endfire Radiation Characteristics for 5G mm-wave Applications

A dual-frequency band high-gain split-ring antenna is proposed for 5G mm-wave applications. The antenna consists of three split ring resonators (SRRs), one is the main SRR which radiates at the first resonant frequency (f
1
=24.5 GHz). The other two resonators are parasitic SRRs which act as directors to get end-fire radiation characteristics for the proposed antenna at f
1
. In addition, the two parasitic SRRs are fed by capacitive coupling with the main SRR to radiate at the second resonant frequency (f
2
=28.5 GHz). The antenna has better radiation characteristics. It has high gain values of 7.9, and 7.5 dBi with radiation efficiencies of 92% and 95% at f
1
, and f
2
, respectively. The proposed antenna is a good candidate for MIMO array at 5G frequency bands utilizing the antenna high gain to improve the system performance.