Integrated Design and Optimization of a Shared-Aperture Dual-Band K/Ka Flat Panel Antenna Array for Enhanced LEO SATCOM Performance

This paper presents a planar dual-band, dual-port patch antenna designed for K/Ka-band satellite communication systems, particularly suitable for Low Earth Orbit (LEO) applications. The proposed radiator integrates both gap-fed and coax-fed methods in a single layer, enabling resonances in the K and Ka bands with minimal complexity. Shorting pins and a coupling conductor are strategically placed to fine-tune impedance matching and enhance port-to-port isolation. A 2x3unit cell array using the same radiator concept demonstrates circular polarization through sequential feeding while reducing the total number of elements. Simulated results confirm stable gain, wide impedance bandwidth, and sufficient cross-polarization discrimination for next-generation satellite communication.