The key elements of the inter-satellite link involve measurement systems and topology analysis. The constellation configuration of space satellites is complex, and the link topology structure under different measurement systems is different. Inter-satellite observation is not conducted between any two satellites, but needs to be designed according to the measurement system and inter-satellite visibility analysis. The observation data of inter-satellite and the observation data between satellites and ground stations are the basic observation quantities for realizing satellite autonomous orbit determination and system time synchronization, which have important significance for the verification of satellite navigation system functions, performance and satellite orbit determination, system time synchronization methods.