空天通信网络关键技术综述

With the information society continuously developing towards networking, ubiquity, and intelligence, the existing terrestrial communication network has been unable to supply the increasing demand for broadband services, ubiqui⁃ tous access, and concealed and reliable transmission. The future communication network requires the realization of allround wireless access. Its further evolution urgently needs to break through the underlying technologies including network architecture and air interface technology. Compared with the terrestrial communication networks, integrated space-airground communication networks can work independently of terrain, and can achieve full coverage including oceans, forests, remote areas, etc. In addition, the information interaction can also be achieved from multiple dimensions. The integrated space-air-ground communication will be one of the key technologies enabling the ubiquitous connection of enormous het⁃ erogeneous users. This paper summarizes the key technologies of aerospace communication networks. Firstly, we introduce the existing space-air-ground communication systems and the diversified application scenarios oriented for the future smart society. Secondly, an overall architecture of the integrated space-air-ground communication networks is presented from the perspectives of space-air-ground physical space, physical-network-application network structure, and effective transmissionresource management-security protection technical route. Subsequently, the key technologies are summarized such as net⁃ working and multiple access, physical layer and resource management, etc. Finally, the technical challenges and trends of future aerospace communication networks are pointed out.