A Miniaturized and Circularly Polarized Antenna with Improved Radiation Efficiency

In this paper, a miniaturized and circularly polarized (CP) antenna with improved radiation efficiency is proposed. The antenna proposed in this paper is based on a printed dipole antenna with its two arms bent around to grow the current path for miniaturization, and the bending process provides two orthogonal directions of current to achieve circular polarization. This leads to a compact design that can better utilize the limited space to achieve good performance. In addition, the radiation efficiency of the proposed antenna is improved by optimizing the winding of the arms. Finally, a highly miniaturized CP antenna is realized with a decent radiation efficiency. The size of the antenna is 0.13 λ 0 × 0.14 λ 0 × 0.01 λ 0 , where λ 0 is the wavelength in vacuum and the simulated radiation efficiency is around 60% across the working bandwidth.