Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Considerations for LDPC codes selection M. Chiani, G. Liva, E. Paolini University of Bologna Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Outline I.Consolidation of Requirements for New Channel Coding Schemes II.Comparison of LDPC Coding Schemes: a Proposal for Benchmarking III.Overview of solutions under investigation within CCSDS IV.CONCLUSIONS

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre I. Consolidation of Requirements for New Channel Coding Schemes

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Consolidation of Requirements for New Channel Coding Schemes SPACE MISSIONS Non-Deep Space (Near-Earth) Deep Space Earth station-spacecraft distance < 2.0 x 10 6 km Earth station-spacecraft distance > 2.0 x 10 6 km CCSDS Mission Category A CCSDS Mission Category B

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Mission Scenarios I.Near Earth at Lagrange Point L2 II.Mars Missions III.Low Earth Orbiter Payload Telemetry for Earth Observation IV.Low Earth Missions with High Rates

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Near Earth at Lagrange Point L2 (e.g. ESA Missions: Darwin, Gaia, Herschel-Planck) X Band at e.g. 10 Mbps 50 MHz available in total; No more than 10 MHz per mission GMSK Modulation Bandwith efficient codes required BW>10MHz Ka (26 GHz or 37 GHz)

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Mars Missions Similar to #1 but Deep Space 50 MHz available in X Band Large BW Ka Band (32 GHz) Constraints in Bandwidth and Link Budget to be evaluated GMSK

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Low Earth Orbiter Payload Telemetry for Earth Observation Critical problem in X Band: 0.35 GHz available band  8PSK TCM developed to this scope (CCSDS & ECSS approved) Constraints mainly in Band occupation. Bandwidth is driver but code efficiency is important too. Ka Band (26GHz) for future very high rate needs. 1.5 GHz wide. BW-eff to be considered from the outset.

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre TDRSS Case Not addressed by CCSDS so far. Should it be? Alternatively,search for commonality?

Montreal – Spring 2004 SPACE LINK SERVICES CODING AND SYNCHRONIZATION WORKING GROUP University of Bologna ITALY ESA – European Space Agency ESOC - European Space Operations Centre Low Earth Missions with High Rates Not for Earth Observation (e.g. successor of Hubble Telescope or Lunar Missions) Same Band as #1 Likely to occupy the complete band Not yet well defined  It may be wise to wait for Frequency Managers to fix strategy