A Compact Dual-Band Circularly Polarized Antenna with Low Profile for BDS Applications

In this paper, a novel dual-frequency circularly polarized (CP) antenna applied to Beidou satellite (BDS) system is presented. CP radiation is achieved by etching slotted circular patches of complementary open-loop resonators, which are excited by a feeding network consisting of a double-layer power divider. The circular patch is miniaturized by a complementary split-ring resonator (CSRR) etched on the patch. The overall dimension of the antenna is only 0.32λ0 × 0.32λ0 × 0.0104λ0, where λ0 is the corresponding free space wavelength at 1.268 GHz. The proposed antenna has 70 MHz (1.23– 1.30 GHz) and 60 MHz (1.51–1.57 GHz) impedance bandwidth and 20 MHz (1.25–1.27 GHz) and 20 MHz (1.55–1.57 GHz) axial ratio bandwidth, respectively. The antenna profile is low, which is easy to install. Because of these performance indexes, the antenna has superior practicability in BDS system. © 2022, Electromagnetics Academy. All rights reserved.