Corner-truncated patch antenna with parasitic elements and circular feed slot for S-band CubeSat applications

Abstract

This study presents a corner-truncated patch antenna with symmetrically loaded parasitic elements and a circular feed slot designed for CubeSat S-band communication applications. The antenna design evolves through successive stages, integrating corner truncations, a slit-ring structure, and segment-circular parasitic patches to enhance impedance matching and polarization performance. In its final configuration, a dual-stacked arrangement with inter-substrate spacing and a vertical capacitive feed further improves current distribution symmetry and broadens the operational bandwidth. Parametric analysis validates the effectiveness of each antenna design refinement, demonstrating improvements in impedance bandwidth, axial ratio bandwidth, and gain performance. The fabricated prototype achieves a wide impedance bandwidth from 1.65 GHz to 2.70 GHz, fully encompassing the CubeSat uplink (2.025–2.110 GHz) and downlink (2.200–2.290 GHz) frequency ranges. It maintains an axial ratio below 3 dB across 1.97 GHz to 2.32 GHz, ensuring efficient circular polarization. Additionally, a stable gain of approximately 7.50 dBic at 2.025 GHz supports reliable communication with ground stations. The combination of compact structure, low profile, and wideband circular polarization makes the proposed antenna a promising candidate for CubeSat communication systems. The novelty of this research lies in the integration of a corner-truncated patch, symmetrically loaded segment-circular parasitic elements, and a circular slit-ring capacitive feed within a dual-stacked substrate configuration to achieve wideband circular polarization and stable unidirectional radiation. • The presented corner-truncated patch antenna operates in widebands at the frequencies from 1.65 GHz to 2.70 GHz, fully encompassing the CubeSat uplink and downlink. • The combination of compact structure, low profile, and wideband circular polarization makes the proposed antenna a promising candidate for CubeSat. • The antenna maintains an axial ratio below 3 dB across 1.97 GHz to 2.32 GHz, ensuring efficient circular polarization. • The antenna provides a maximum gain of 7.5 dBic at 2.025 GHz.