Data communication bus interface for modular architecture of small satellites

This paper illustrates general data communication architecture of AraMiS project (Italian acronym standing for “modular architecture for small satellites) and inter-tile data communication bus interface structure of the small modular satellites. The dual redundant data bus will provide exchange of information in almost all operative conditions and connect all the electronic peripherals, supporting the data exchange speed required by the different sub-systems composing the satellite. The proposed architecture uses differential bus with galvanic isolation among all the connected modules in order to have fault tolerance, good signal integrity and to connect as many tiles in series or in parallel. The proposed structure has been tested in almost all possible fault conditions and the simulation and actual results show reliable transmission and reception of signal from one module to the other even under different types of fault conditions. System stability is guaranteed by the proposed characteristic of each subsystem in such a way that any number of modules can be connected to the communication bus without impairing overall performance and stability. This work presents the bus interface circuit located between the processor and the communication channel and also the fault tolerance analysis with different possible types of faults.