PERFORMANCE ANALYSIS OF PROBE-FED CIRCULARLY-POLARIZED MODERATELY-THICK MICROSTRIP ANTENNAS DESIGNED UNDER THE NULL REACTANCE CONDITION
Keywords:microstrip antennas, circular polarization, axial ratio, input impedance matching, nonlinear regression
This work presents a performance analysis of probe-fed circularly-polarized moderately-thick microstrip patch antennas. Five typical geometries are designed according to the null reactance condition. A nonlinear regression, based on HFSS simulations, is implemented in order to identify the most robust geometry, regardÂing the manufacturing process. The analysis focus is on broadside axial ratio degradation and frequency deviation parameters. ExperiÂmental results validate the proposed approach and the nonlinear regression calculations.
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