Fractal and Metasurface Based Low Profile Circularly Polarized Microstrip Antenna

Abstract

Design of a low-profile and compact circularly polarized microstrip antenna is proposed and investigated based on fractal radiator and high impedance metasurface. Circular polarization and size reduction is achieved by embedding fractal tree like structures at the corners of a square patch. High impedance metasurface is placed at the half of the total height of the FR4 substrate, to enhance the gain of the proposed antenna. Study revealed that the antenna is very compact with layout of 0. 3λ₀ x 0.3 λ₀ x 0 .012 λ₀ at 2.3 GHz, global bandwidth (reflection coefficient, axial ratio and gain bandwidth) of 16 MHz (2.293 GHz - 2.309 GHz) and stable gain of about 2.5 dBic. Proposed Design is single feed and small sized, therefore can be find applications in many portable/IOT wireless communication systems.