Metadata Fields - SMAP L1A Radiometer Time-Ordered Parsed Telemetry

This page provides a description of all metadata fields within the SMAP L1A Radiometer Time-Ordered Parsed Telemetry (SPL1AP) product. All metadata fields are described in Table 1.

For a description of data fields for this product, refer to the Data Fields document.

Table 1. Description of File-Level Metadata Fields
Representative ISO Class HDF5 Metadata Subgroup HDF5 Subgroup/Attribute Description/Valid Values1
DQ_DataQuality DataQuality Scope TBD
CompletenssOmission/evaluationMethodType directInternal
CompletenessOmission/measureDescription Fraction of time period within the half orbit when radiometer data appear to be missing.
CompletenessOmission/nameOfMeasure Percent of Missing Data
CompletenessOmission/value <A measure between 0 and 100>
CompletenessOmission/unitOfMeasure Percent
domainConsistency/evaluationMethodType directInternal
DomainConsistency/measureDescription Percent of science telemetry packets that were deemed usable for radiometer processing.
DomainConsistency/nameOfMeasure Percent of Usable Science Data Packets.
DomainConsistency/value <A measure between 0 and 100>
DomainConsistency/unitOfMeasure Percent
EX_Extent Extent description Time range of the telemetry that contains both full-band and sub-band radiometer data downlinked from the SMAP spacecraft.
westBoundLongitude <Longitude measure between -180 degrees and 180 degrees>
eastBoundLongitude <Longitude measure between -180 degrees and 180 degrees>
southBoundLatitude <Latitude measure between -90 degrees and 90 degrees>
northBoundLatitude <Latitude measure between -90 degrees and 90 degrees>
rangeBeginningDateTime <Time stamp that indicates the initial time element in the product>
rangeEndingDateTime <Time stamp that indicates the final time of data in the product>
LI_Lineage/LE_ProcessStep ProcessStep processor Soil Moisture Active Passive (SMAP) Mission Science Data System (SDS) Operations Facility
stepDateTime <A date time stamp that specifies when the product was generated>
processDescription Parses Radiometer Telemetry into discretely defined elements. Converts temperature and voltage measures from data numbers to engineering units.
documentation <A reference to software description document>
identifier L1A_RADIOMETER_SPS
runTimeParameters <Specify any run time parameters if they were used>
SWVersionID <A software version identifier that runs from 001 to 999>
softwareDate <A date stamp that specifies when software used to generate this product was released>
softwareTitle L1A_Radiometer_SPS
timeVariableEpoch J2000
epochJulianDate 2451545.00
epochUTCDate 2000-01-01T11:58:55.816Z
ATBDTitle <document that describes Level-1A Radiometer processing>
ATBDDate <Time stamp that specifies the release date of the ATBD>
ATBDVersion <version identifier>
algorithmDescription Parses Radiometer Telemetry into discretely defined elements. Converts temperature and voltage measures from data numbers to engineering units.
algorithmVersionID <An algorithm version identifier that runs from 001 to 999>
LI_Lineage/LE_Source L0B_Radiometer. Ephemeris.  Attitude, Antenna Azimuth. SCLK-UTC Correlation, LeapSeconds, Reconstructed High Resolution Earth Orientation, ScaleFactorsFile, VoltageCurrentCoeffFile, TempCoeffFile, SignedMaskFile1 description <Description of each input file>
fileName <Complete file name of the input data product>
creationDate <A date stamp that specifies when the input data product was generated>
version <The SMAP Composite Version ID associated with the input data product>
identifier <The short name associated with the product>
DOI <A digital object identifier associated with the product, if available>
DS_Dataset/MD_DataIdentification DataSetIdentification creationDate <Date when the Level-1A Radiometer data product file was created>
CompositeReleaseID <SMAP Composite Release ID associated with this data product – See section 3.3>
fileName <Name of the Level-1A Radiometer output data file>
originatorOrganizationName Jet Propulsion Laboratory
shortName SPL1AP
SMAPShortName L1C_S0_HiRes
UUID <A universally unique identifier for each data granule>
abstract Parsed and reformatted SMAP radiometer telemetry with UTC time stamps. The Level-1A Product contains both fullband and sub-band radiometer data. The product also includes information about spacecraft position and attitude during the time period when the radiometer data were acquired.
characterSet utf8
credit The software that generates the Level-1A Radiometer product was designed and implemented at the Goddard Space Flight Center in Greenbelt, Maryland. The data system that automates its production was designed and implemented at the Jet Propulsion Laboratory, California Institute of Technology in Pasadena, California.
Language eng
purpose This product enables users to interpret and read the contents of the SMAP Radiometer telemetry using clearly delineated and described data elements.
status on-going
topicCategoryCode geoscientificInformation
QACreationDate <The date of the QA product that accompanies the Level-1A Radiometer data granule was generated>
QAFileName <The name of QA product>
QAAbstract An ASCII product that contains statistical information on data product results. These statistics enable data producers and users to assess the quality of the data in the data product granule.
DS_Series/MD_DataIdentification SeriesIdentification revisionDate <Date and time of the software release that was used to generate this data product>
CompositeReleaseID <SMAP Composite Release ID that identifies the release used to generate this data product – See section 3.3>
longName SMAP Radiometer Level-1A Product. Parsed Radiometer Instrument Telemetry
shortName SPL1AP
identifier_product_DOI <digital object identifier>
resourceProviderOrganizationName National Aeronautics and Space Administration
abstract Parsed and reformatted SMAP radiometer telemetry with UTC time stamps. The Level-1A Product contains both full-band and sub-band radiometer data. The product also includes information about spacecraft position and attitude during the time period when the radiometer data were acquired.
characterSet utf8
credit The software that generates the Level-1A Radiometer product was designed and implemented at the Goddard Space Flight Center in Greenbelt, Maryland. The data system that automates its production was designed and implemented at the Jet Propulsion Laboratory, California Institute of Technology in Pasadena, California.
language eng
purpose This product enables users to interpret and read the contents of the SMAP Radiometer telemetry using clearly delineated and described data elements.
status on-going
topicCategoryCode geoscientificInformation
pointOfContact National Snow and Ice Data Center, Boulder, Colorado
PSDPublicationDate <Date of publication of the Product Specification Document>
PSDEdition <Edition identifier for the Product Specification Document>
PSDTtitle Soil Moisture Active Passive Mission L1A Radiometer Product Specification Document
SMAPShortName L1A Radiometer
mission Soil Moisture Active Passive (SMAP)
maintenanceAndUpdateFrequency asNeeded
maintenanceDate <Specifies a date when the next update to this product is anticipated>
format HDF5
formatVersion 1.8.9
MD_AcquisitionInformation AcquisitionInformation platform/antennaRotationRate 14.6 rpm ( 13.0 rpm )
platformDocument/publicationDate <The date of publication of the document that describes the SMAP platform, if available to the general public>
platformDocument/edition <The edition of publication of the document that describes the SMAP platform, if available to the general public>
platformDocument/title <The title of the publication of the document that describes the SMAP platform, if available to the general public>
platform/description The SMAP observatory houses an L-band radiometer that operates at 1.40 GHz and an L-band radar that operates at 1.26 GHz. The instruments share a rotating reflector antenna with a 6 meter aperture that scans over a 1000 km swath. The bus is a 3 axis stabilized spacecraft that provides momentum compensation for the rotating antenna.
platform/identifier SMAP
radarDocument/publicationDate <The date of publication of the document that describes the SMAP radar instrument, if available to the general public>
radarDocument/edition <The edition of publication of the document that describes the SMAP radar instrument, if available to the general public>
radarDocument/title <The title of the publication of the document that describes the SMAP radar instrument, if available to the general public>
radar/description The SMAP radar instrument employs an L-band conically scanned system and SAR processing techniques to achieve moderate resolution (1 km) backscatter measurements over a very wide 1000 km swath.
radar/identifier SMAP SAR
radar/type L-Band Synthetic Aperture Radar
radiometerDocument/publicationDate <The date of publication of the document that describes the SMAP radiometer instrument, if available to the general public>
radiometerDocument/edition <The edition of publication of the document that describes the SMAP radiometer instrument, if available to the general public>
radiometerDocument/title <The title of the publication of the document that describes the SMAP radiometer instrument, if available to the general public>
radiometer/description The SMAP L-band Radiometer records V-pol, H-pol, and 3rd and 4th Stokes brightness temperatures at 40 km resolution at 4.3 Megatbits per second with accuracies of 1.3 Kelvin or better.
radiometer/identifier SMAP RAD
radiometer/type L-Band Radiometer
SD_OrbitMeasuredLocation OrbitMeasuredLocation argumentOfPerigee <The angle in the satellite’s orbit plane between the point of perigee and ascending node. The angle is measured in the direction of spacecraft motion>
cycleNumber <The SMAP satellite flies in a cycle that repeats after 117 orbits. This element specifies the cycle of orbits when the data were taken. First cycle is assigned the number 1>
eccentricity <The eccentricity of the satellite orbit>
epoch 2000-01-01T11:58:55.816Z
equatorCrossingDateTime <A time stamp that specifies the date and time of ascending node crossing for the current orbit>
equatorCrossingLongitude <The longitude of the ascending node crossing for the current orbit>
inclination <The angle between the spacecraft’s orbital plane and the Earth’s equatorial plane. An angle greater than 90 degrees indicates a orbit retrograde path>
meanMotion <The constant angular speed that would be required for a body travelling in an undisturbed elliptical orbit with the specified semimajor axis to complete one revolution in the actual orbital period, expressed as a number of revolutions per day>
orbitDirection <SMAP Level-1 and Level-2 products appear in half orbit granules. This element provides direction of orbital path relative to equatorial plane.Values are "ascending" or "descending">
halfOrbitStartDateTime <A time stamp that specifies the date and time of the instant the spacecraft crosses either the southernmost point or the northernmost point in its path, marking the beginning of the half orbit>
halfOrbitStopDateTime <A time stamp that specifies the date and time of the instant the spacecraft crosses either the southernmost point or the northernmost point in its path, marking the end of the half orbit>
orbitPathNumber <The SMAP satellite flies in a cycle the repeats after 117 orbits. This element specifies which of the 117 possible paths the spacecraft flew when the data in the file were acquired. The orbitPathNumbervaries from 1 to 117.>
orbitPeriod <Time required to complete a the spacecraft orbit>
reference_CRS <A description of the coordinate reference system used to describe spacecraft orbital data>
revNumber <The count of orbits from beginning of mission to the orbit that the spacecraft flew when the data in the file were acquired. Orbit zero begins at launch and extends until the spacecraft crosses the southernmost point in its path for the first time. Orbit one commences at that instant.>
rightAscensionAscendingNode <The angle eastward on the equatorial plan from the vernal equinox to the orbit ascending node.>
semiMajorAxis <The length of the semi-major axis of the spacecraft orbit.>
1 Brackets indicate a description of potential valid values, not an absolute value. For example, valid values for the Subgroup algorithmVersionID range from 001 to 999, which is indicated by the following description: <An algorithm version identifier that runs from 001 to 999>