A novel circularly polarized metasurface inspired regular triangle patch antenna (RTPA) with enhanced gain and bandwidth is proposed in this paper. The antenna is composed of a triangular patch-driven element sandwiched between a 3×3 sub-wavelength square patch metasurface array and the ground plane. Initially, the RTPA is designed, and the ground plane is etched with fractal slots to produce degenerate modes for circular polarization. A metasurface array is used as a superstrate to improve gain and bandwidth in terms of impedance and axial ratio (AR). Another advantage of using a metasurface is the reduction of cross-polar radiation, particularly when employing a triangular-shaped patch antenna. The asymmetry of this structure leads to cross-polar components contributed by dominant modes rather than higher-order modes, and the use of a metasurface markedly diminishes these components. The proposed antenna's experimental results show a 10 dB return loss (|S11|) with a metasurface demonstrates a measured impedance bandwidth and axial ratio bandwidth of 760 and 350 MHz, respectively. The antenna exhibits right-hand circular polarization with a measured gain of 5.87 dBic at the operating frequency.
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