Abstract: In order to meet the rapidly changing needs of civil and commercial aerospace TT&C and the explosive growth of TT&C tasks caused by the rapid development of small satellites and large constellations，software-defined technology，which is considered a revolutionary technology that changes the rules of the game，was introduced from the internet industry into aerospace TT&C systems，a software-defined aerospace TT&C system architecture was proposed，and a new round of technological innovation in the TT&C system was realized.Firstly，the architecture and existing problems of the traditional TT&C system were analyzed，and then the technical characteristics of the software-defined aerospace TT&C system were discussed，such as hierarchical design standards，open application interfaces，centralized system control，and flexible reorganization of basic resources.Then，the advantages of the architecture and four key technologies including standard interfaces and specifications，software-defined RF front-end，software-defined channel and softwaredefined baseband were analyzed，and the development of software-defined TT&C system was prospected.The research results show that compared with the traditional TT&C system，the software-defined aerospace TT&C system architecture can better meet the needs for TT&C resources of the growing aerospace industry.

Key words: aerospace TT&, C, software defined TT&, C, system architecture, software and hardware decoupling, dynamic refactoring