2.3.1 spase://CNES/NumericalData/CDPP-AMDA/MEX/MARSIS/mex-marsis-ele total electron content 2015-10-15T10:14:00 The level 5 TEC data are derived following a method described in details by Mouginot et al. Planetary Space Science, V56, 2008. The correction method consists in finding the three parameters [ a1 ; a2 ; a3 ] defining the signal distortion phase Δφ induced by the ionosphere. In the time domain, the ionosphere distortion generates a delay and a spreading of the radar pulse. It is clearly visible on MARSIS radargram without correction. A by-product of the ionospheric correction is the TEC, that can be easily obtained from the [ a1 ; a2 ; a3 ] parameters. [ a1 ; a2 ; a3 ] are investigated in ordrer to get Δφ with the best SNR As initial conditions for this optimization, we use the parameters fitting with a simplified Gaussian density-profile of the ionosphere. Then the optimization is done by using the following constraints: * A constraint on the vertical position of the surface echo estimated with the digital elevation model MOLA. * A constraint on the SNR. The signal amplitude must be maximal after correction. spase://CNES/Person/W.Kofman DataProducer spase://CNES/Person/C.Grima DataProducer MARSIS TEC documentation ftp://psa.esac.esa.int/pub/mirror/MARS-EXPRESS/MARSIS/MEX-M-MARSIS-5-DDR-SS-TEC-V1.0/DOCUMENT/MARSIS_EAICD_TEC.PDF spase://SMWG/Repository/CNES/CDPP-AMDA Online Open http://amda.cdpp.eu NetCDF PSA MEX-M-MARSIS-5-DDR-SS-TEC-[EXT1]-V1.0 L5 spase://CNES/Instrument/CDPP-AMDA/MEX/MARSIS Waves 2005-06-19T04:03:28Z 2007-09-30T23:41:11Z PT1S PT10S Mars Data Quality Description : * -1: percentage of low SNR data not available * 0: no low SNR data * 1: less than 25% low SNR data * 2: less than 50% low SNR data * 3: less than 75% low SNR data * 4: more than 75% low SNR data tec mex_marsis_tec Total electron content derived from the ionosphere distortion correction phys.density;phys.electron m-2 TimeSeries Other quality flag mex_marsis_tecflag TimeSeries Other