A High Gain Circularly Polarized Fractal Antenna for X-band Application

A fractal single-band patch antenna is designed for X-band operation, with a wide bandwidth of 920 MHz from 9.24 GHz to 10.17 GHz. The antenna attains circular polarization (CP) with a >3-dB axial ratio (AR) for 157 MHz bandwidth ranging from 9.93 GHz to 10.08 GHz. It has an exceptional return loss of -49.01 dB, a compact design with a diameter of 30 mm, and a high gain of 9.34 dBi, making it well-suited for high-directivity applications. The antenna's efficiency of 96% is primarily attributed to the Rogers RT5880 substrate, having a relative dielectric constant of 2.2 and loss tangent of 0.0009, making it appropriate for high-frequency stability. This model outperforms existing CP fractal antennas, making it a compelling candidate for high-performance X-band applications.