High Gain, Wideband Antenna with Thin Rectangular Slits for 5G Applications in the 38 GHz and 39 GHz Bands

This paper introduces a simple rectangular microstrip patch antenna with a wide bandwidth and high gain to operate in the 38 and 39 GHz bands, designed specifically to meet the requirements of 5G. The impedance bandwidth was enhanced by integrating two slits into the radiating patch. The antenna was constructed using a dielectric substrate made of Rogers RT/Duroid 5880 with a thickness of 0.186 mm, a dielectric constant of 2.2, a tangent loss of 0.0009, and an overall volume of 5 × 8.2 × 0.186 mm . In addition, the antenna achieves an impedance bandwidth (≤ -10 dB) of 3.11 GHz, ranging from 37.226 GHz to 40.336 GHz. The antenna gain varies from 6.55 dBi at the highest frequency of the operating band, rising to 9.028 dBi at the band’s lowest frequency, with 9.027 dBi at the 38 GHz resonance frequency. The radiation efficiency also slightly changes over the operating band, varying from 86.97% at the upper frequency to 88.96% at the lower frequency, with 88.29% at the resonance frequency of 38 GHz. The antenna is well matched to its feeding line, as shown by the low VSWR of 1.01186 and the high return loss of 60 dB achieved at the resonance frequency. The design was optimized using the CST simulator, while the HFSS simulator was used to verify the antenna performance. The proposed structure offers good radiation characteristics and high radiation gain, making it suitable for 5G applications.