A dual-band mm-wave compact antenna is proposed in this paper. A quarter-wave half-slot
resonator is used instead of a half-wave slot to achieve miniaturization of the antenna size. The antenna
consists of two stacked half-slot resonators to radiate at two frequencies, f1 D 24 GHz and f2 D 28:5 GHz,
with the same microstrip line feed. By using this stacked structure, a dual-band is obtained and the two
resonant frequencies become independently matched with a minor effect on each other. Measurements show
the proposed antenna has an impedance bandwidths of 6:3% and 15% at f1 and f2, respectively; furthermore,
the antenna has good radiation characteristics. The antenna gains in addition to the radiation efciencies
at f1 and f2, are 3:5dBi, 92%, 4dBi, and 95% respectively. The equivalent circuit model for the proposed
antenna is introduced to show the electrical behavior of the antenna. Finally, the antenna design is inserted
in multiple-input multiple-output (MIMO) system. The proposed antenna is analyzed and optimized using
ANSYS HFSS EM simulator and its equivalent circuit is performed by Agilent Advanced Design System
(ADS). The simulated as well as measured results show good agreement. The designated antenna resembles
good candidate for 5G wireless communication systems.