Design of Four-Element Dual-Frequency Circular-Polarization Microstrip Array Antenna

Abstract

A method of designing a dual-frequency circularpolarization patch antenna array composed with four patch elements and a feeding network here. The design formulas are provided in detail. The antenna designed by the method is directly fed by a 50 Omega microstrip line feeder, and doesn't need drilling in printed circuit board , thus it's easy to fabricate and suitable for normal application. Then an example of patch antenna working at 1.9 GHz and 2.4 GHz in the manner of circular-polarization is given. The return loss, axial ratio and radiation pattern all meet the design requirements according to the simulation results given by ADS software.