Comparative Study of Rectangular and Circular Microstrip Patch Antenna Using Duriod Substrate for 5g Application

Abstract

Microstrip patch antennas (MPAs) are widely employed in wireless communication systems because of their low profile, lightweight structure, low fabrication cost, and ease of integration with planar circuits. However, selecting the most suitable patch geometry remains a major design challenge, as antenna shape significantly influences impedance matching, bandwidth, gain, and radiation characteristics. Despite the extensive use of rectangular and circular microstrip patch antennas, limited studies have provided a comprehensive comparison of their performance using RT/Duroid 5880 substrate at the 3.5 GHz 5G band. This study addresses this gap by comparatively evaluating rectangular and circular microstrip patch antennas to identify the geometry best suited for 5G applications. The antennas were designed and simulated using the High Frequency Structure Simulator (HFSS), and their performance was assessed based on return loss (S11), voltage standing wave ratio (VSWR), realized gain, bandwidth, and directivity. Both antenna geometries resonated successfully at 3.5 GHz; however, the rectangular antenna exhibited superior overall performance, achieving a lower return loss of −28.85 dB, lower VSWR of 0.6297, higher realized gain of 7.8059 dB, and greater directivity of 2.5882 dB compared to the circular antenna, which recorded −24.89 dB return loss, 0.999 VSWR, 7.1306 dB gain, and 2.4898 dB directivity. Although the circular antenna provided a slightly wider bandwidth (200 MHz) than the rectangular antenna (188 MHz), the results demonstrate that the rectangular microstrip patch antenna offers superior impedance matching and radiation performance, making it a more suitable candidate for efficient and reliable sub-6 GHz 5G wireless communication systems.