L-shaped monopole slot antenna for Circular Polarization

Abstract

A wideband circularly polarized L-shaped monopole slot antenna is designed and fabricated. The measured results demonstrate that the antenna has an Axial Ratio <; 3 dB and a reflection coefficient <; -10 dB and 23% Circular Polarization bandwidth. As the monopole quarter-wavelength slot antenna occupies half of the area on the corner of circuit board as compared to a half-wavelength slot antenna, this antenna is attractive for compact wireless devices that operate at low frequencies in which planning for the smallest circuit board area combined with the shortest length for signal routing are the two major concerns.