A Slot-Coupled Fed Three-Band Broadband High-Gain Circularly Polarized Magneto-Electric Dipole Antenna

This paper introduces a broadband, high-gain circularly polarized (CP) magneto-electric (ME) dipole antenna with slot-coupled feeding. The design employs a microstrip line to deliver energy through a vertical ground-cut slot, thereby exciting the radiating structure. A coplanar square parasitic ring positioned adjacent to the horizontal patch simultaneously induces multiple resonant modes. This configuration combines intrinsic ME-dipole resonances with tailored CP characteristics, establishing circular polarization from dual-orthogonal eigenmodes exhibiting equal amplitude and 90° phase quadrature. Full-wave simulations validate broadband operation achieving |S11|<-10 dB between 3.52-6.35 GHz, delivering 10.25 dBic peak realized gain, while maintaining 3-dB axial ratio (AR) coverage across 3.52-5.30 GHz.