2026-07-09 Latest Published
By Xu Tan
Han Lin
Zhonggen Wang
Wenyan Nie
Progress In Electromagnetics Research M, Vol. 139, 1-10, 2026
Abstract
This study proposes a high-performance miniaturized wideband circularly polarized (CP) metasurface (MTS) antenna for WLAN and 5 GHz wireless communication systems. The design innovatively utilizes a hybrid embedded structure, where regular octagonal patches are incorporated into the gaps of modified X-shaped primary radiating elements to increase edge capacitance and lower resonant frequency, thereby achieving antenna miniaturization. To effectively excite the orthogonal degenerate modes required for CP radiation, a characteristic mode analysis (CMA) was employed to guide the design of the feed network. A feeding structure consisting of a hook-shaped microstrip line and a symmetrical stepped cross-slot is designed to achieve CP excitation via a 90˚ phase delay introduced by path length differences. Measured results demonstrate that the antenna achieves a -10 dB impedance bandwidth of 34.2% (4.38-6.19 GHz) and a 3 dB axial ratio (AR) bandwidth of 23.9% (4.68-5.95 GHz). Regarding radiation characteristics, the radiation efficiency remained stable above 75%, and the peak realized gain reached 5.26 dBic. The experimental results verified that the proposed design achieved stable CP and radiation performance within a miniaturized footprint.