Unified Communication Infrastructure for Small Satellites

Paper number

IAC-09.B4.6A.1

Author

Mr. Albert Ferrer Florit, University of Dundee, United Kingdom

Coauthor

Dr. Steve Parkes, University of Dundee, United Kingdom

Year

2009

Abstract

Typical state of the art on-board communication infrastructure comprises two independent communication architectures. Command and control operations use a robust low data rate bus such as MIL-STD-1553B or CAN Bus. Payload data-handling systems rely on high data rate interconnection networks such as SpaceWire. A unique communication architecture would simplify the system design and deployment while reducing the mass and energy required. Unfortunately the solutions specifically targeted for hard real-time control generally do not provide the data throughput necessary for transporting and managing large amounts of data. On the other hand, communications architectures for high-speed, large-volume data transfer are generally not designed to provide the guaranteed low latency and high reliability required for mission critical, hard real-time control systems.

SpaceWire-RT has been designed to provide the best of the two worlds by implementing different quality of services that fulfills the needs of each application under a unique network architecture. SpaceWire-RT is built on top of SpaceWire, a space-proven technology that is simple to implement and use, and is being deployed on many space missions. SpaceWire standard describes a low-latency interconnection network with arbitrary topology that handles variable data rates. SpaceWire-RT implements a quality of service layer to provide determinism and additional robustness for command and control operations. 

SpaceWire-RT has two principal dimensions: reliability and timeliness. Reliability is provided using a redundancy scheme with alternative paths for packets to be routed over. Timeliness is provided using a time-division multiplexing of network bandwidth to ensure that a packet can be delivered within certain time constraints.  Event-driven, time-driven, high and low rate data sources can be accommodated without penalties in the network performance.

The full paper will present an overview of SpaceWire-RT including results of prototyping. The new on-board communication paradigm will be compared with previous existing solutions to show the benefits of unifying the communications system: faster development, lower risk and a significant save in terms of cost, power and mass.

Abstract document

IAC-09.B4.6A.1.pdf

Manuscript document

IAC-09.B4.6A.1.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.