Low Earth Orbit (LEO) satellite communication systems have evolved into a critical component of global broadband networks, enabling wide-area connectivity, IoT services, and intelligent multilayer satellite–terrestrial integration. Despite rapid advancements in constellation deployment, routing mechanisms, resource management, and LEO–5G/6G convergence, the long-term evolution of research themes and network architectures remains insufficiently mapped. This study analyzes 2420 Web of Science articles published between 1995 and 2025 and applies bibliometric techniques, main path analysis, and edge-betweenness clustering to identify the core technological trajectories shaping the LEO communication domain. The results reveal five major phases of development: foundational constellation design, multilayer architecture integration, performance and QoS optimization, 6G-driven intelligent connectivity, and secure collaborative networking.
