PAGE CONTENTS
Objectives
The objective of this activity is the development of a CAN bus solution to be used in platform and payload avionics of telecom satellites. The proposed CAN solution has to cover all the aspects related to the introduction of the CAN bus in telecom satellites, from the physical and protocol layer definition up to the test and validation procedure definition.
Challenges
Key project challenges:
- Implementation of a single solution common to both RS485 and ISO11898 networks
- Network start-up and sub networks synchronization
- Network redundancy and reconfiguration procedures
- Hardware implementation of additional protocol functions (ECCIPC)
- Automatic test procedures implementation
- EMC test result analysis due to weak flight representativeness of the test bench hardware
System Architecture
Two different physical layers have been analysed and implemented according the CABCOM study requirements:
- RS-485 network: four sub network composed of 31 nodes each operated in time multiplexing by a single master
- ISO-11898 network: a single network with 120 nodes operated in time multiplexing by a single master
The upgraded Spacebus Neo avionics architecture replaces the OBDH lines dedicated to the payload busses with the CAN bus. The high-level payload bus performances have been therefore inherited from the Spacebus 4000 requirements.
Plan
As a First Task, the system requirements for a robust CAN solution for SATCOM have been defined.
Second Task focused on the inclusion of a standard protocol layer implementation and its impact on the overall SATCOM architecture.
The Third task, focused on the design, implementation and justification of the selected CAN bus solution and its test set-up.
In the Fourth Task both simulated and hardware in the loop protocol tests have been performed and relevant results analysed. Also the EMC test campaign has been completed for the ISO118908 physical layer.
Fifth and last task has been dedicated to the study documentation finalization and closeout.
Current Status
Completed.
