Page 192 - 2023-Vol19-Issue2

188 | Gaid & Ali

Fig. 13. The antenna gain and radiation efficiency vs
operating frequencies using CST.

The comparison includes a range of performance metrics
such as S11, antenna dimensions, impedance bandwidth, gain,
and radiation efficiency. The proposed antenna outperforms
all antennas presented in references [23]- [32] concerning
impedance bandwidth and exhibits superior gain compared
to the antennas in [23], [25], [26], [30], and [31]. Addition-
ally, while the proposed antenna operates in three frequency
bands, the other antennas in the table are either single or dual-
band, except for the antenna in [26]. However, despite the
triple-band functionality of the antenna in [26], our proposed
antenna demonstrates better performance in terms of both
gain and impedance bandwidth.

V. CONCLUSION Fig. 14. The surface current distribution using HFSS at (a)
27.9 GHz, (b) 38.4 GHz, and (c) 56 GHz.
This paper presented a low-profile tri-band antenna for 5G
applications in the frequency bands of 28 GHz, 38 GHz, and
60 GHz. The antenna’s matching was enhanced using an inset
feed, and the radiating element was optimized by adding a
p-shaped slot to improve its characteristics. The design used a
Rogers RT/Duroid-5880 substrate resulting in a final antenna
size of 8 x 8.5 x 0.508 mm³. The proposed antenna achieved
maximum S11 values of -15.4 dB, -18 dB, and -26.4 dB at the
resonant frequencies, respectively. The bandwidths achieved
are 1.26 GHz, 1.08 GHz, and 12.015 GHz, respectively. In ad-
dition, the gains realized at the resonance frequencies are 7.96
dBi, 6.82 dBi, and 7.93 dBi, respectively, with high radiation
efficiencies of 88%, 84%, and 90%. In addition, it is observed
that the antenna radiates at the highest power in the broadside
direction at 27.9 GHz, while the maximum radiation occurs
at – 41/ 41 degrees and – 30/30 degrees at 38.4 GHz, and 56
GHz, respectively. The proposed design was optimized using