A Comparative Study on the Influence of Bandwidth Axial Ratio Using Radiator Variations in Microstrip Antennas

Abstract

Polarization is a significant parameter in microstrip antennas that can be shaped based on the radiating element (radiator) with specific characteristics. This research focuses on designing antennas using radiator variations to obtain polarization parameters such as axial ratio. The axial ratio bandwidth (ARBW) values produced by each antenna model are analyzed. The antenna radiator has a rectangular base shape using an FR4 substrate with a dielectric constant of 4.6 and a thickness of 1.6 mm, operating at a frequency of 2450 MHz. The radiating element has a stub as a structural variable to achieve impedance matching, and this variable does not affect the axial ratio value. From the basic rectangular shape, the antenna radiator is modified using the truncated corner method, which involves cutting the corners of the radiating element. The truncated corner models consist of triangular, circular, and square shapes. Simulation results show that the square truncated corner model has the largest ARBW value of 150.3 MHz, while the triangular and circular shapes have ARBW values of 103.1 MHz and 118.8 MHz, respectively. The best axial ratio value at the resonant frequency is achieved by the triangular truncated corner shape. These results indicate that the difference in radiator shape affects the axial ratio value and ARBW.