Design and Simulation of a Compact Microstrip Antenna for 5G Applications at the (37 – 40) GHz Band

Abstract

This paper proposes a simple, low-profile rectangular microstrip patch antenna for 5G applications in the 37-40 GHz band. The initial design involved a basic rectangular microstrip patch antenna, which was modified to operate efficiently in the target frequency band. The antenna's performance was improved by adjusting the S 11 and VSWR through an inset feed to improve the matching between the feeding microstrip line and the radiating element. Further improvements were made by inserting two slits, leading to resonating at 37.9 GHz and 39.68 GHz and expanding the impedance bandwidth. The antenna was designed using a 0.381 mm thick Rogers RT/Duroid-5880 substrate with a dielectric constant of 2.2 and a loss tangent of 0.0009. The final design measured 6.11  6  0.381 mm 3 and achieved minimum S 11 values of – 32.14 dB and – 17.8 dB at 37.9 GHz and 39.68 GHz, respectively. The antenna also achieved VSWR values of 1.05 and 1.3 at the resonance frequencies. Moreover, an impedance bandwidth of 3.57 GHz extending from 36.65 GHz to 40.22 GHz was achieved. The proposed antenna achieved a maximum gain of approximately 7.98 dBi over frequencies ranging from 37.8 GHz to 38.6 GHz and a minimum of 6.2 dBi at 40.2 GHz. Additionally, the antenna realized a radiation efficiency above 96 % across the operational band. The antenna design, simulations, and optimizations were performed using HFSS, while CST was used to validate the simulation re-sults. The simulation outcomes from both software simulators indicated a high level of agreement.