CEOS ICF

1
CEOS ICF
Baseband Data Archive InterChange Format
Stéphane MBAYEGAEL ConsultantStephane.Mbaye_at_gael
.fr
Commitee on Earth Observation Satellites
(CEOS) Working Group on Information Systems and
Services (WGISS) 12th meeting Sioux Falls, USA
2
Rationale

• Document status
• Review Item Discrepancies (RID)
• Main concepts
• Format overview
• Metadata File description
• Signal Data File description

3
Document status

• 21/04/2000 Draft 0 - Creation of the document
• 29/08/2000 Draft 1 - Use of XML Schema instead
  of DTD
• 09/01/2001 Draft 2 - Includes outputs of
  Bangkok ATT meeting
• 09/04/2001 Draft 3 - Consolidated document
  (last draft)
• XX/05/2001 GAEL-CEOS-ICF-060.2 Issue 1,
  Revision 0

4
Review item discrepancies
5
Main concepts general requirements

• Make data exchange possible between facilities
• Decrease the number of archive format translators
• Baseband compliant

Doc. 2.1
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Main concepts(cont.) - Properties

• Interchange
• Baseband Data Concept
• Multi-missions and multi-sensors
• Extendibility
• Hard/Software and OS independence

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Format overview

• Hard-disk organization (normative)
• File naming convention (character set and XML
  extension)
• lt 2 Gigabytes
• Magnetic Tape encapsulation (informative)
• No hardware compression
• lt 2 Gigabytes
• Network transfer (informative)

Doc. 3.1
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Metadata File XML

• CEOS ICF Metadata File format is XML
• XML Namespace
• http//wgiss.ceos.org/ceos-icf/ceos-icf-v1.0-09042
  001 (TBC)
• Validation (XML Schema)
• http//wgiss.ceos.org/ceos-icf/ceos-icf-v1.0-09042
  001.xsd (TBC)

Doc. 4.1
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Metadata File - Markups convention

• Characters are always lowercases
• Words are separated by an underscore
• Abbreviations and acronyms only with set of
  initials

? Sample of correct CEOS ICF markups
(informative)   ltceos_icfgt ltnssdc_identifiergt lt
sensorgt ltelement_setgt  
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Metadata File - Extendibility

• Only  add information  to keep CEOS ICF
  integrity
• Removing a mandatory element is forbidden
• Usually for specific parameters
• Extend using other XML namespaces

? Correct sensor extension (informative)   ltsenso
rgt ltnamegtHRVlt/namegt ltnumbergt2lt/numbergt
ltspotmirror_step value23/gt
ltspotsensor_modegtXIlt/spotsensor_modegt lt/sensorgt
 
Doc. 4.2
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Metadata File - Reference systems

• Units expressed in SI from the BIPM (m, kg, s,
  etc.)
• World Geodetic System 1984 (NIMA)
• Universal Time Coordinated (UTC) from the BIPM

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Metadata File - Built-in data types

• integer
• timeInstant (UTC and ISO-8601)
• string (Universal Code Set - ISO-10646)
• double (IEEE 754-1985)
• uriReference (RFC-2396 and RFC-3732)

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Metadata File - UML model
Doc. Appendix B
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Metadata File - Root element
? Fraction of schema for CEOS ICF Root Element
(normative)   ltxsdelement nameceos_icf
minOccurs1 maxOccurs1gt   ltxsdcomplexTypegt
ltxsdsequencegt ltxsdelement
nameversion
typeversion
minOccurs1 maxOccurs1/gt  
ltxsdelement nameplatform
typeplatform
minOccurs1 maxOccurs1/gt  
ltxsdelement nameprocessing_log
typeprocessing_log
minOccurs0 maxOccurs1/gt  
ltxsdelement namesignal_data
typesignal_data
minOccurs1 maxOccurs1/gt
lt/xsdsequencegt lt/xsdcomplexTypegt   lt/xsdelem
entgt  
Doc. 4.6
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Metadata File - Root example

• lt?xml version1.0?gt
•  
• ltceos_icf xmlnshttp//wgiss.ceos.org/ceos-icf-v
  1.0-09042001gt
•  
• ltversiongt
• lt/versiongt
• ltplatformgt
• lt/platformgt
• ltsignal_datagt
• lt/signal_datagt
•  
• lt/ceos_icfgt

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Metadata File - Platform element
Doc. 4.8
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Metadata File - Orbit element
platform
element_set
0..1
orbit
0..1
element_set
0..1
orbit
0..1
number integer
cycle integer
track integer
0..1
attitude_set
0..1
attitude_set
Doc. 4.10
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Metadata File - Signal Data description
Doc. 4.20, 4.21
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Metadata File - Other elements

• Version (for CM)
• Processing (logging)
• Facility (identifying actors)
• System (identifying hardware, firmware of
  software)

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Signal Data File - Properties

• Binary file (close to telemetry format)
• Sequence of signal data record (minimal
  repetitive pattern)
• No redundancy
• No encryption
• CRC and Checksum corrections applied
• No compression (configurable for each block)
• PN decoded
• Frame synchronized
• Chronological order
• Byte aligned (at block levels)
• Only information contained in Metadata File can
  be removed

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Signal Data File - Example of mapping
Signal Data File Record
Minimal repetitive pattern of telemetry
Native telemetry format
Signal Data File format