Design of A Circularly Polarized Crescent-Cut Circular Patch Antenna for S-Band Application

This paper presents the design and analysis of a circularly polarized dual-band slotted patch antenna intended for S-band applications using simulation software Advanced Design System (ADS). This design features a circular patch with a crescent-shaped stub. Copper is used for both patch and ground, while FR-4 material is used as substrate. Proposed antenna operates at two resonant frequencies: 2.36 GHz and 2.68 GHz, with effective bandwidth of 2.26–2.44 GHz and 2.66–2.69 GHz, respectively. The designed antenna achieves circular polarization (RHCP) at 2.36 GHz with a reflection coefficient of -47.30 dB and a directivity of 5.85 dBi. Additionally, designed antenna achieves a reflection coefficient of -14.58 dB and directivity of 4.90 dBi at 2.68 GHz. The proposed antenna exhibits an enhanced circular polarization with an axial ratio of 0.43 dB at 2.35 GHz. The Voltage Standing Wave Ratio (VSWR) values of 1.02 at 2.36 GHz and 1.48 at 2.68 GHz demonstrates excellent impedance matching across both frequency bands. The designed antenna highlights promising performance suitable for S-band applications, demonstrating its potential for deployment in wireless communication system.