A multi-layer approach of orthogonally fed circularly polarized microstrip array antenna for enhanced gain
AbstractA new circularly polarized microstrip array antenna using the orthogonal feed technique is proposed in this paper. The antenna has a multi-layer structure and a new 3-way power divider employing the both-sided microwave integrated circuit technology is designed to configure the feed network of the array. Circular polarization (CP) is realized by creating a quadrature phase difference between orthogonal feed circuits of the patches. The multi-layer structure gives flexibility to adjust the patch spacing that helps to reduce the sidelobe level of the antenna. It is found that the multi-layer structure exhibits a gain of about 2 dB higher than that of a single layer structure by means of sidelobe reduction. The proposed structure also exhibits good CP performances that are verified by a good agreement of measured and simulated results. Simple and compact structure makes the antenna suitable for various wireless applications.