The ESA EO SatelliteBased Data Dissemination System DDS' Did you know that EO data may be already ou

1
The ESA EO Satellite-Based Data Dissemination
System (DDS). (Did you know that EO data may be
already out of your door?)
86 TB of delivered products!
Stefano Badessi ESA ESRIN EUI-TP

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The Envisat Data Acquisition
Artemis

• Visibility
• 10/14 Orbits at Kiruna
• 14/14 Orbits at ESRIN via ARTEMIS.

Envisat

• Orders via Internet.

3
Distribution of E.O. Data

• Earth Observation Data may be disseminated to
  users in three different ways
• Media support (DVD, tape,)
• Pro Low Costs of the Media, High Capacity
• Cons High Delays, Shipment Costs.
• Electronic delivery via ground networks (i.e.
  Internet FTP)
• Pro High diffusion of Internet Low costs for
  low bit rates
• Cons High Costs for high bit rates Not yet
  suitable for multicast often unavailable on
  emergencies areas.

• Electronic delivery via satellite link (i.e.
  DDS)
• Pro Multicast High availability independently
  from ground infrastructures High bit rates and
  Near Real Time receptions
• Cons High Cost of the satellite bandwidth.

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The DDS Today

• 2 Uplink Stations (ESRIN Frascati, Kiruna)
• 29 User Stations
• 8.2 MHz allocated on Eutelsat W1
• 2 channels for capacity use optimisation
• Fast channel 6.0 Mbps
• Slow channel 96 Kbps.

Eutelsat W1
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DDS Coverage
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DDS Architecture
Eutelsat W1

• IP over DVB-S
• Internet return Channel
• RRMProtocol

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Linux DDS Receiver
1.2 m _at_ 47 dBW 1.8 m _at_ 45 dBW

• Less than 2000

• Less than 100

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Win Receiver Kit

• PRO
• Cost attractive Kit (less than 350 ), to be
  installed into a commercial PC
• Windows Look feel interface.
• CONS
• Stability of Windows XP/2000 w.r.t. Linux

• Pilot phase ongoing with 10 selected users

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Open Dissemination Service

• MERIS RR Products
• Resolution 1.2 Km
• About 600 MB size per orbit.
• East Mediterranean, 14 July 2004
• Bands 7 (red), 5 (green), and 2 (blue),
  corresponding to visible light, were used to
  create this image
• Other products foreseen for open dissemination.

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DDS A Success story

• DDS Started operations on 8th of March 2002
• 24 TB of data disseminated up to 1st October
  2004
• About 550,000 products disseminated
• Delivery success rate gt99
• 3.6 Users addressed as average by each Product
  for a total of 86 TB of data delivered
• 29 Receiving Stations installed in 9 European
  Countries

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Conclusions

• DDS is a fully operational and reliable service
  for Envisat data dissemination serving European
  users form March 2002, using IP over DVB-S.

• IP over DVB-S with terrestrial return link and
  RRMP protocol is a reliable and very cost
  attractive technique in order to broadcast /
  multicast continuously high volume of data via
  satellite.

• Coverage stretches over North Africa, Russia and
  Middle East and could be exploited for projects
  needing fast data availability.

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Contacts

DDS Operational Web Site (http//dwlinkdvb.esrin.
esa.it/DDS)
EOHelp - ESA Earth Observation Missions Helpdesk
ESA-ESRINPost-Office Box 64I-00044 Frascati
(Italy)Tel [phone] Working hours
0830-1715 Fax [phone]E-mail
eohelp_at_esa.int