Spacefibre: a very high speed network for space flight applications

SpaceWire has proved very successful since the release of the standard by ECSS. This success is due to the versatility of SpaceWire and its inherent simplicity and low implementation cost (low gate count). SpaceWire can be used as a simple point to point link to transfer data from an instrument to onboard memory or in a more sophisticated architecture using routers. The architecture can be tailored to suit the specific application, adding bandwidth and support for fault tolerance where it is needed. SpaceWire has a fairly high cable mass and uses a non DC balanced signalling technique that makes galvanic isolation difficult. SpaceFibre is a proposed very high speed serial data link intended to complement and extend the capabilities of SpaceWire: improving the data rate by a factor of 10, reducing the cable mass by a factor of four and providing galvanic isolation. This paper gives the background and requirements for SpaceFibre showing how the proposed standard builds on the existing SpaceWire standard. The technical background for SpaceFibre will be discussed, highlighting other high-speed networking standards and pointing out key similarities and differences. Although SpaceFibre shares a number of features with existing high-speed standards, the technical decisions made for SpaceFibre explicitly reflect the challenges posed by the application domain. The paper then presents the prototyping and demonstration work being carried out by the University of Dundee under ESA contract. Copyright IAF/IAA. All rights reserved.