Short product names


Full product name
Ionospheric total electron content


Integrated electron density along the line of sight from Swarm to GNSS satellites

Output variables

TimestampmsTime stamp in UTC1CDF_EPOCH
LatitudedegreeGeographic latitude1CDF_DOUBLE
LongitudedegreeGeographic longitude1CDF_DOUBLE
RadiuskmGeographic radius1CDF_DOUBLE
GPS_PositionkmX-,Y-,Z-coordinates (WGS84) of the GPS satellite3CDF_DOUBLE
LEO_PositionmX-,Y-,Z-coordinates (WGS84) of the LEO satellite3CDF_DOUBLE
L1mGPS L1 carrier phase observation1CDF_DOUBLE
L2mGPS L2 carrier phase observation1CDF_DOUBLE
P1mGPS P1 code phase observation1CDF_DOUBLE
P2mGPS P2 code phase observation1CDF_DOUBLE
S1-GPS signal-to-noise ratio or raw signal strength on L11CDF_DOUBLE
S2-GPS signal-to-noise ratio or raw signal strength on L21CDF_DOUBLE
Absolute_STECTECUAbsolute slant TEC1CDF_DOUBLE
Absolute_VTECTECUAbsolute vertical TEC1CDF_DOUBLE
Elevation_AngledegreeElevation Angle1CDF_DOUBLE
Relative_STECTECURelative slant TEC1CDF_DOUBLE
Relative_STEC_RMSTECURoot mean square error of relative slant TEC1CDF_DOUBLE
DCBTECUGPS receiver differential code bias1CDF_DOUBLE
DCB_ErrorTECUError of the GPS receiver differential code bias1CDF_DOUBLE


Product identifier TECxTMS_2F
Definition Time series of the ionospheric total electron content
Input data GPS RINEX observation and navigation files (GPSX_RO_1B), Swarm satellite ephemeris (MODX_SC_1B) GPS and Swarm satellite ephemeris (AUX_GPSEPH) GPS transmitter biases(AUX_DCB_2F) Leap seconds (AUX_USLEAP)
Input time span 3 days
Spatial representation Line representation of GPS –Swarm link
Time representation 1-s time series for TEC and 1 day for DCB
Units TECU (1016 electrons/m2)
Resolution 1E-8 TECU
Uncertainty 2 TECU
Quality indicator Relative_STEC_RMS (RMS deviation between code and carrier phases) and DCB_Error
Data volume ~4 MB / day / satellite
Output data CDF file with time series
Output time span 1 day
Latency 6 min
Update rate 1 per day
Notes The cadence of the TECxTMS_2F data has changed from 10-s (0.1 Hz) to 1-s (1 Hz) at:
2014-07-14 06:42:59 for Swarm A
2014-07-14 06:06:46 for Swarm B
2014-07-14 08:15:59 for Swarm C
It is recommended to use absolute VTEC data with corresponding elevation angles of the GPS rays of at least 50°.