Novel miniaturization broadband circular polarization antenna using single plate

In this paper, a compact ring-slot coupling type circularly polarized antenna (CPA) with circular power divider (PD) is proposed for broadband communication applications. The circular PD is placed interior of circular radiation sheet. A prototype operating at 2.4 GHz-WLAN band has been fabricated and measured. A critical design parameter is selected from the primary research and optimized using the particle swarm optimization method with a numerically manipulated fitness function. The proposed antenna shows desirable performances in simulation and also in measurement with a reduced size. Measured reflection coefficient, axial ratio (AR), radiation pattern, and antenna gain agree well with simulation results.