Ground communications is the academic and engineering discipline concerned with the principles, technologies, and systems for transmitting and receiving information on, from, or to the Earth's surface. As a research field, it investigates the design, implementation, and optimization of communication links between terrestrial points or between ground-based infrastructure and non-terrestrial assets such as satellites or aircraft. Key characteristics include the study of signal propagation in the terrestrial environment and through the atmosphere, frequency management, ground station design, and ensuring reliable data transfer; its significance lies in enabling critical functions like command and control, data acquisition, navigation, and operational support for diverse applications ranging from space exploration to telecommunications networks.