Large-Scale Spaceborne Deployable Active Phased-Array Antenna Design Using Rigid-Flex Boards for LEO Satellite Constellation

Satellite communication (SATCOM) systems in low Earth orbit (LEO) require compact, high-performance deployable phased-array transceivers for real-time communication. Conventional phased-array antenna PCBs are constrained by size and flexibility, and high-frequency signal transmission often requires connectors, which can result in insertion loss and mechanical fragility. To address these challenges, this study presents a connector-free, foldable high-frequency design utilizing a rigid-flex PCB architecture. The proposed transceiver system comprises a 6-layer rigid-flex PCB with a 4096-element phased array, optimizing launch volume and deployed antenna aperture. A foldable transmission line is incorporated to enhance highfrequency signal transmission, minimizing signal reflection and insertion loss. Furthermore, a low-loss via structure replaces traditional laser-drilled vias with mechanically drilled blind vias to reduce surface roughness and high-frequency losses. Electromagnetic simulations and experimental measurements were conducted to validate the effectiveness of the design. The results indicate improvements in transmission efficiency compared to conventional connector-based systems, while mechanical stability during launch and deployment is maintained. This study offers a cost-effective and high-performance solution for next-generation LEO SATCOM systems.