A new compact [Formula: see text] microstrip patch antenna array design for future 5G applications is presented in this paper. The proposed antenna array consists of square slot loaded with four radiating patch elements. The corporate feed network has been implemented for the excitation of the array. The feed line is connected to the square slot patch through a quarter-wave transformer matching network. The proposed array is designed on an FR-4 substrate with a dielectric constant of 4.4, thickness of 1.6[Formula: see text]mm and loss tangent (tan[Formula: see text] of 0.02. It has a compact dimension of 9.590[Formula: see text] 17.802[Formula: see text]. The proposed structure has been designed and simulated by using commercially available HFSS software. The simulated results (reflection coefficient, gain, efficiency, radiation pattern) are verified through the measurement process to confirm the validity of the design concept. The measurement results are in good agreement with the simulated results. The proposed structure resonates at 38.1[Formula: see text]GHz with a [Formula: see text]10[Formula: see text]dB impedance bandwidth of about 3700[Formula: see text]MHz (36.5[Formula: see text]GHz to 40.2[Formula: see text]GHz). The reflection coefficient at 38.1[Formula: see text]GHz is [Formula: see text]34[Formula: see text]dB, with a maximum gain of 7.81[Formula: see text]dB. The proposed square slot loaded patch antenna array is very promising for 5G communications at 38[Formula: see text]GHz band (37–40[Formula: see text]GHz).
