SpaceWire


Developed under ESA auspices in the late 90’s, SpaceWire formal standardisation via ECSS was envisaged in an early stage in order to provide space users with a directly usable specification. SpaceWire was standardised in 2003: ECSS-E-ST-50-12C.

Within a SpaceWire network the processing nodes are connected through low-error rate, low-footprint, low-cost, low-latency, full-duplex, point-to-point serial links and wormhole switches.

SpaceWire has been supplemented by a set of standards for higher-protocols supporting onboard SpaceWire Data-Handling networks:


 
 
 Applications and benefits
  
The SpaceWire standard offers many advantages over other comparable communications technologies and it extends the concept of serial links to Modular Systems based on On-board Networks. Its main advantages are:
  • it facilitates the construction of high-performance onboard data-handling systems
  • it helps reduce system integration costs
  • it facilitates compatibility between data-handling sub-systems
  • it encourages re-use of data handling equipment across several different missions

Designed for use in space applications, it served first as an interface between the instruments and the mass memory for on-board storage of spacecraft Telemetry. It gained popularity for space applications because of its simple circuitry, low power consumption and low-error rate. It is now widely use by the platform sub-systems to send Telecommands (e.g. OBC, SSMM and the RIU) as on the Bepi Colombo platform.

The classical On-Board Computing System (OBCS) based on one-processor and related multi-drop bus architectures is too limiting for future space missions. ESA anticipated these needs by initiating the SpW Network Technology Program several years ago. In this scope, Modular Architecture for Robust Computing: MARC provides a unified and robust approach to future spacecraft data management systems.


 
 
 Modular Architecture for Robust Computing (MARC) for Spacecraft Avionics, Payload Processing and Data Handling.
 
 
MARC - Spacewire backplane
 
MARC is an innovative hardware development by SEA to unify future spacecraft processing systems to create a SpaceWire network based, scalable, fault tolerant, high performance capability, and robust system solution suitable for Spacecraft platform and data handling applications.

The design features a SpaceWire Active Backplane and Modules with SpaceWire interfaces; these permit optimisation of the system to suit different applications. The developed demonstration system uses many recently developed European technologies such as the LEON2FT processor and the SpaceWire 10X Router as well as commercial technologies such as DDR and FLASH for the Mass Memory Module. The design uses technologies that have a defined component level roadmap to a radiation tolerant flight system.

The potential applications for MARC are extremely broad, encompassing single spacecraft with modest platform and instrument requirements, to high data rate instruments mounted on multiple formation-flying spacecraft.

The project has completed the hardware build and the test phase. MARC is suitable for use in the development of flight software.

Avionics applications include:

  • Platform command and control
  • Science spacecraft data handling and payload processing
  • Deep space missions requiring a high level of autonomy
  • Planetary robotic systems
  • Complex and/or multiple payloads


  
 
  
Last update: 4 April 2012


Related links

 •  Spacewire homepage (http://spacewire.esa.int)
 •  Spacewire conferences (http://spacewire-conference.org/)