Compact wideband circularly polarized planar monopole antenna for integrated wireless applications

Abstract This work proposes a small, wideband circularly polarized planar monopole antenna. The antenna comprises a modified C-shaped radiating patch and a truncated rectangular ground plane with a small open-ended slot to achieve a wideband circular polarization property. The proposed antenna has a compact volume of 0.57 λ 0 × 0.45λ 0 × 0.024λ 0 (where λ 0 is the free space wavelength at resonant frequency of 4.5 GHz). It provides a measured fractional impedance bandwidth of 50.70% and fractional 3 dB axial ratio bandwidth of 45.04%. The measured peak gain of the antenna is 7.4 dBi. It also maintains a gain of more than 6 dBi throughout the entire band. The mechanism of circular polarization is also described herein. A parametric investigation of various design parameters has also been prepared herein. The proposed model was simulated using the High Frequency Structure Simulator, and measurements were conducted to validate the simulated results. The simulated and measured results of the various characteristics of the proposed antenna are presented. Owing to its low-profile, wideband, and circular polarization characteristics, the proposed antenna is applicable for different wireless applications.