Hybrid phase error analysis for dual-polarized reflectarray antenna using asymmetric split patch element

ABSTRACT A hybrid phase error analysis for dual-polarized reflectarray antenna using asymmetric split patch element is proposed in this article. The asymmetric split patch consists of a four-leaf patch and two split rings of different size where small one makes the patch asymmeric along y-axis and large one is used for impedance matching. And a complete 360° phase shift is obtained by using variable-size approach and flipping split patch 180° along y-axis. Then, we use hybrid phase error analysis approach to analyze and optimize the influence of phase sensitivity, quasi-periodic influence and phase constant on the reflectarray antenna. The simulated results show that maximum of element phase sensitivity is reduced by 275°/mm and element quasi-periodic phase error is dropped by 38°. Furthermore, dual-polarized reflectarray composed of 676 asymmetric split patch elements is designed, fabricated and measured. The measured gain of the proposed antenna is 29.9 dBi @10.0 GHz with aperture efficiency of 46%. The −1 dB gain bandwidth is 12% @10.0 GHz. The measured results show that the proposed antenna can improve phase accuracy effectively by using hybrid phase error analysis approach with asymmetric split patch.