Broadband satellite communication is an indispensable part of modern communication systems. This paper introduces signal modulation identification and channel equalization technologies in broadband satellite communication.which can improve the performance and stability of the system, so as to better deal with the problems of multi-path interference and time-varying distortion in satellite communication, In practical applications, it is necessary to select appropriate technologies and algorithms to optimize and adjust different signal modulation types to further improve the performance and stability of the system, This paper provides a reference for signal modulation identification and channel equalization technoogies in broadband satelite communication, and provides support for the development of satellite communication systems in the future.