| DATA_SET_DESCRIPTION |
Data Set Overview: The Mars Express (MEX) Radio Science (MaRS) Data Archive is a time-ordered collection of raw and partially processed data collected during the MEX Mission to Mars. For more information on the investigations see the MaRS User Manual [MARSUSERMANUAL2004] in the MaRS DOCUMENT/MRS_DOC folder. This is a Phobos Gravity measurement covering the time 2013-12-29T08:55:06 to 2013-12-29T19:02:03.000. This data set was collected during the MEX Extended Mission Phase 4 (EXT4) 2013 to 2014. There were four types of scientific measurements conducted during Extended Mission: Solar Conjunction, Occultation, Bistatic Radar and Gravity where one has to distinguish between gravity measurements conducted on Phobos as well as global gravity measurements on Mars which were conducted around apocenter and target gravity measurements on Mars which were conducted around pericenter over interesting geophysical structures. For more information see INST.CAT or the MaRS User Manual [MARSUSERMANUAL2004]. For all measurements if not indicated otherwise Transponder 1 onboard the s/c was used. Transponder 2 is designed to be a backup.Mission Phase Definition: It should be noted that the Mars Express (MEX) Radio Science (MaRS) group uses mission phases which deviate from the ones defined in the MISSION.CAT files given by ESA in order to keep the keywords and abbreviations consistent for Mars Express, and Rosetta. For Venus Express other definitions are used. Those mission phase abbreviations are also used in the data description field of the dataset_id. MaRS mission name | abbreviation | time span : Near Earth Verification | NEV | 2003-06-02 - 2003-07-31 ---------------------------------------------------------------- Cruise 1 | CR1 | 2003-08-01 - 2003-12-25 ---------------------------------------------------------------- Mission Commissioning | MCO | 2003-12-26 - 2004-06-30 ---------------------------------------------------------------- Prime Mission | PRM | 2004-07-01 - 2005-12-31 ---------------------------------------------------------------- Extended Mission 1 | EXT1 | 2006-01-01 - 2007-09-30 ---------------------------------------------------------------- Extended Mission 2 | EXT2 | 2007-10-01 - 2009-12-31 ---------------------------------------------------------------- Extended Mission 3 | EXT3 | 2010-01-01 - 2012-12-31 ---------------------------------------------------------------- Extended Mission 4 | EXT4 | 2013-01-01 - 2014-12-31 ---------------------------------------------------------------- Extended Mission 5 | EXT5 | 2015-01-01 - 2016-12-31 ---------------------------------------------------------------- Extended Mission 6 | EXT6 | 2017-01-01 - 2018-12-31 Data files ---------- Data files are: The tracking files from Deep Space Network (DSN) and from the Intermediate Frequency Modulation System (IFMS) used by the ESA ground stations. Level 1a to level 2 data, the predicted and reconstructed Doppler and range files are archived. All Level 1A binary data files will have the file name extension eee : .DAT IFMS Level 1A ASCII data files will have the file name extension eee : .RAW Level 1B and 2 tabulated ASCII data files will have the file name extension eee : .TAB Binary data files will have the file name extension .DAT Data levels ---------- It should be noted that these data levels which are also used in the file names and data directories are PSA data levels whereas in the PDS label files CODMAC levels are used. PSA data level | CODMAC level ----------------------------- 1A | 1 1B | 2 2 | 3 Data Set Identifier ------------------- The 'DATA_SET_ID' is a unique alphanumeric identifier for the data sets. It looks something like: XXX-Y-ZZZ-U-VVV-NNNN-WWW Acronym | Description | Example -------------------------------------------------------- XXX | Instrument Host ID | MEX -------------------------------------------------------- Y | Target ID | M (for Mars) or X for | | other like for example | | for sun during solar | | conjunction measurements -------------------------------------------------------- ZZZ | Instrument ID | MRS -------------------------------------------------------- U | Data level (here | 1/2/3 (Data set | CODMAC levels are used) | contains raw, edited | | and calibrated data) --------------------------------------------------------- VVV | MaRS mission phase |MCO | (deviate from the |(for values see above) | mission phases) | --------------------------------------------------------- NNNN | 4 digit sequence number | 0123 | which is identical to | | the Radio Science | | Volume_id | --------------------------------------------------------- WWW | Version number | V1.0 MaRS data were originally archived as volumes rather than data sets. However, ESA PSA does not uses volume but data set. To avoid confusion it was specified that one MaRS data volume is equal one data set. Thus the data set was also assigned a 4 digit sequence number which is identical to the one used in the volume_id. If the data_set_id is known it is automatically specified on which volume the data set is found.VOLUME_ID--------- The VOLUME_ID is a unique alphanumeric identifier for a single RSI data volume, including a complete measurement. Two kinds of Volume ID's are used, the ESA and RSI Volume_Id: ESA PSA Volume_Id: ------------------ The Volume ID is formed using a mission identifier, an instrument identifier of 3 characters, followed by an underscore character, followed by a 4-digit sequence number. In the 4-digit number, the first one represents the kind of measurement, the remaining digits define the range of volumes in the volume set. The first digit of the 4-digit sequence number: 0: Commissioning 1: Occultation 2: Gravity 3: Solar Conjunction 4: Bistatic Radar 5: Passive/Active Checkouts 6: Swing-bys/Fly-bys 7: Cometary Coma Observations The Volume-ID looks like: XXXXX-ZZZZ Acronym | Description | Example ---------------------------------------------------------- XXXXX | Mission ID and Instrument ID | MEXMRS ---------------------------------------------------------- ZZZZ | 4 digit sequence number | 0123 RSI Volume_Id: -------------- The Radio Science Volume_Id is a number which is incremented measurement by measurement, independent what kind of measurement was conducted. The RSI Volume ID is used within the DATA_SET_ID. The Radio Science Volume_Id can be found in the logbook located in DOCUMENT/RSI_DOC.Descriptive files----------------- Descriptive files contain information in order to support the processing and analysis of data files. The following file types are defined as descriptive files with extension eee : .LBL PDS label files .CFG IFMS configuration .AUX Ancillary files (event files, attitude files, ESOC orbit files, products, SPICE files) .TXT Information (text) filesFile naming convention: All incoming data files will be renamed and all processed data files will be named after the following file naming convention format. The original file name of the incoming tracking data files will be stored in the corresponding label file as source_product_id. The new PDS compliant file name will be the following: rggttttlll_sss_yydddhhmm_qq.eee Acronym | Description | Examples : r | space craft name abbreviation | M | R : Rosetta | | M : Mars Express | | V : Venus Express | ------------------------------------------------------------- gg | Ground station ID: | 43 | | | 00: valid for all ground stations; | | various ground stations or independent | | of ground station or not feasible to | | appoint to a specific ground station or | | complex | | | | DSN complex Canberra: | | --------------------- | | 34 : 34 m BWG (beam waveguide) | | 40 : complex | | 43 : 70 m | | 45 : 34 m HEF (high efficiency) | | | | ESA New Norcia antenna: | | ----------------------- | | 32 : 35 m | | | | ESA Cebreros antenna: | | --------------------- | | 62 : 35 m | | | | ESA Malargue antenna: | | --------------------- | | 84 : 35 m | | | | DSN complex Goldstone: | | ---------------------- | | 10 : complex | | 14 : 70 m | | 15 : 34 m HEF | | 24 : 34 m BWG | | 25 : 34 m BWG | | 26 : 34 m BWG | | 27 : 34 m HSBWG | | | | ESA Kourou antenna: | | ------------------- | | 75 : 15 m | | | | DSN complex Madrid: | | ------------------- | | 54 : 34 m BWG | | 55 : 34 m BWG | | 63 : 70 m | | 65 : 34 m HEF | | 60 : complex | ------------------------------------------------------------- tttt | data source identifier: | TNF0 | | | Level 1A and 1B: | | ---------------- | | ODF0 : ODF closed loop | | TNF0 : TNF closed loop (L1A) | | T000-T017 : TNF closed loop (L1B) | | ICL1 : IFMS 1 closed loop | | ICL2 : IFMS 2 closed loop | | ICL3 : IFMS RS closed loop | | IOL3 : IFMS RS open loop | | R1Az : RSR block 1A open loop | | R1Bz : RSR block 1B open loop | | R2Az : RSR block 2A open loop | | R2Bz : RSR block 2B open loop | | R3Az : RSR block 3A open loop | | R3Bz : RSR block 3B open loop | | z:1...4 subchannel number | | ESOC : ancillary files from ESOC DDS | | DSN0 : ancillary files from DSN | | SUE0: ancillary and information files | | coming from Stanford University | | center for radar astronomy | | | | Level 2: | | ------- | | UNBW : predicted and reconstructed | | Doppler and range files | | ICL1 : IFMS 1 closed loop | | ICL2 : IFMS 2 closed-loop | | ICL3 : IFMS RS closed-loop | | ODF0 : DSN ODF closed loop file | | T000-T017 : TNF closed loop file | | RSR0 : DSN RSR open loop file | | RSRC : DSN RSR open loop file containing | | data with right circular | | polarization (only solar | | conjunction measurement) | | RSRL : DSN RSR open loop file containing | | data with left circular | | polarization (only solar | | conjunction measurement) | | NAIF : JPL or ESTEC SPICE Kernels | | SUE0 : ancillary information and | | calibration files coming from | | Stanford University center for | | radar astronomy | | | --------|------------------------------------------|-------- lll | Data archiving level | L1A | L1A : Level 1A | | L1B : Level 1B | | L02 : Level 2 | | L03 : Level 3 | --------|------------------------------------------|-------- sss | data type | | | | IFMS data files level 1A: | | ------------------------- | | D1X uncalibrated Doppler 1 X-Band | | D1S uncalibrated Doppler 1 S-Band | | D2X uncalibrated Doppler 2 X-Band | | D2S uncalibrated Doppler 2 S-Band | | C1X Doppler 1 X-Band equip. calibration | | C1S Doppler 1 S-Band equip. calibration | | C2X Doppler 2 X-Band equip. calibration | | C2S Doppler 2 S-Band equip. calibration | | RGX uncalibrated X-Band range | | RGS uncalibrated S-Band range | | MET meteo file | | AG1 AGC 1 files | | AG2 AGC 2 files | | RCX X-Band range equip. calibration | | RCS S-Band range equip. calibration | | | | DSN data files level 1A: | | ------------------------- | | ODF original orbit files (closed loop) | | RSR radio science receiver open-loop file| | TNF file (closed loop) | | | | ESOC ancillary data level 1A: | | ----------------------------- | | ATR attitude file, reconstructed | | EVT orbit event file | | OHC orbit file, heliocentric cruise | | OMO orbit file, marscentric, operational | | | | DSN Calibration files level 1A: | | ------------------------------- | | TRO DSN tropospheric calibration model | | MET DSN meteorological file | | ION DSN ionospheric calibration model | | BCL SUE Bistatic radar temperature | | calibration | | | | DSN ancillary data level 1A: | | ----------------------------- | | DKF DSN Keyword File | | MON DSN monitor data | | NMC DSN Network Monitor and Control file | | SOE DSN Sequence of Events | | EOP DSN earth orientation parameter file | | ENB SUE Experimenter Notebook | | MFT SUE Manifest files | | LIT DSN Light time file | | HEA DSN Data collection list | | OPT DSN Orbit and timing geometry file | | | | DSN Browse Plots level 1A: | | -------------------------- | | BRO bistatic radar 4-panel plots (browse)| | | | IFMS data files level 1B: | | ------------------------- | | D1X uncalibrated Doppler 1 X-band | | D1S uncalibrated Doppler 1 S-band | | D2X uncalibrated Doppler 2 X-band | | D2S uncalibrated Doppler 2 S-band | | C1X Doppler 1 X-band equip. calibration | | C1S Doppler 1 S-band equip. calibration | | C2X Doppler 2 X-band equip. calibration | | C2S Doppler 2 S-band equip. calibration | | RGX uncalibrated X-band range | | RGS uncalibrated S-band range | | MET meteo | | AG1 AGC 1 | | AG2 AGC 2 | | RCX X-band range equip. calibration | | RCS S-band range equip. calibration | | | | DSN ODF data files level 1B: | | ----------------------------- | | DPS S-band Doppler | | DPX X-band Doppler | | RGS uncalibrated S-Band ranging file | | RGX uncalibrated X-Band ranging file | | RMP uplink frequency ramp rate file | | | | DSN calibration data level 1B: | | ----------------------------- | | MET meteorological file | | | | IFMS data level 2: | | ----------------- | | D1X uncalibrated Doppler 1 X-Band | | D1S uncalibrated Doppler 1 S-Band | | D2X uncalibrated Doppler 2 X-Band | | D2S uncalibrated Doppler 2 S-Band | | RGX uncalibrated X-Band range | | RGS uncalibrated S-Band range | | RCX X-Band range equip. calibration | | RCS S-Band range equip. calibration | | | | IFMS Browse plots level 2 | | ------------------------- | | B1X Quick look plots of calibrated | | Doppler 1 X-band | | B1S Quick look plots of calibrated | | Doppler 1 S-band | | B2X Quick look plots of calibrated | | Doppler 2 X-band | | B2S Quick look plots of calibrated | | Doppler 2 S-band | | | | DSN level 2 data: | | ----------------- | | DPX calibrated Doppler X-band | | DPS calibrated Doppler S-band | | RGS calibrated S-band ranging file | | RGX calibrated X-band ranging file | | BSR bistatic radar power spectra | | SRG bistatic radar surface reflection | | geometry file | | | | DSN level 2 calibration data: | | ---------------------------- | | SRF Surface Reflection Filter Files | | | | orbit files level 2: | | -------------------- | | PTW Doppler & range prediction two-way | | PON Doppler & range prediction on | | RTW reconstructed Doppler & range orbit | | file two-way | | RON reconstructed Doppler & range orbit | | file one-way | | LOC heliocentric state vector file | | | | Constellation file Level 2: | | --------------------------- | | MAR Mars constellation file | | VEN Venus constellation file | | P67 Churyumov-Gerasimenko | | constellation file | | | | SPICE kernel files level 2: | | --------------------------- | | BSP binary spacecraft/location | | kernel file | | FRM frame kernel file | | ORB orbit numbering file | | PBC predicted attitude kernel file | | PCK planetary constant kernel | | SCK space craft clock kernel | | TLS leap second kernel file | | | | Science data level 3: | | --------------------- | | SCP solar corona science | --------|------------------------------------------|-------- yy | Year | 04 --------|------------------------------------------|-------- ddd | Day of year | 153 --------|------------------------------------------|-------- hhmm | Sample hour, minute start time | 1135 | For IFMS files this is the ESOC | | reference time tag which usually | | coincides with the first sample time. | | For IFMS Ranging files however this is | | not true. Here the reference time tag | | is two-way light time before the first | | actual measurement. | --------|------------------------------------------|-------- qq | Sequence or version number | 01 --------|------------------------------------------|-------- eee | .DAT binary files (Level 1A) | .RAW | .TAB ASCII table data file | | .AUX ancillary file | | .CFG IFMS configuration file (Level 1B) | | .LBL PDS label files | | .TXT information files | | .RAW ASCII data files (Level 1A) | | .LOG Processing log files (Level 2) | Processing (DSN) : TNF's are screened for 'bad' data points by the JPL Radio Metric Data Conditioning Team (RMDCT) before the files are processed to ODF's. The TNF's included in this archive, however, are the pre- screened versions. The open-loop (RSR) data in the archive have been assembled from individual records (packets) into files. They have not otherwise been processed. The Level 2 radio occultation data have been processed as follows. The RSR samples were digitally filtered to reduce bandwidth; in the process they were also converted from 16-bit I and 16-bit Q complex integer samples to 64-bit I and 64-bit Q double precision complex floating point samples. The complex floating point samples were Fourier transformed and estimates made of the carrier amplitude and frequency and their uncer- tainties. The reconstructed spacecraft trajectory, planetary epheme- rides, records of uplink and downlink tuning, and other data were used to calculate the expected carrier frequency at the receiving antenna. The Level 2 products are tables of the observed amplitude, its uncertainty, the observed frequency, its uncertainty, and the difference between the observed and the expected frequency as a function of time. Separate tables have been created for each RSR. The Level 2 bistatic radar spectra (SPC) have been processed as follows. The RSR samples were converted from 16-bit I and 16-bit Q complex integer samples to 64-bit I and 64-bit Q double precision complex floating point samples. In the process they were digitally corrected for non-uniform spectral response of the receiving system. This was done by computing spectra from series of time samples and dividing each spectrum by the square root of a power spectrum computed from many minutes of noise. The amplitude of the samples was then adjusted so that power spectra in each receiver channel would have an amplitude proportional to kTsysB where k is Boltzmann's constant, Tsys is the receiver system temperature in Kelvin, and B is the width of one frequency bin (spectral resolution) in the power spectrum. Then the power spectra (e.g., XR*conj(XR)) and cross spectra (e.g., XR*conj(XL)) were computed.Structure of DATA Directory: Please note that the following description lists all possible subfolders. If however there is no data to fill some of these folders they will not be generated. |-DATA | |-LEVEL1A | | |-CLOSED_LOOP | | | |-DSN | | | | |-ODF Orbit Data Files | | | | |-TNF Tracking and Navigation Files | | | | | | | |-IFMS | | | |-AG1 Auto Gain Control 1 data files | | | |-AG2 Auto Gain Control 2 data files | | | |-DP1 Doppler 1 data files | | | |-DP2 Doppler 2 data files | | | |-RNG Ranging data files | | | | | |-OPEN_LOOP | | |-DSN | | | |-RSR Radio-Science Receiver data files | | | |-LEVEL1B | | |-CLOSED_LOOP | | | |-DSN | | | | |-ODF Orbit Data Files | | | | | | | |-IFMS | | | | |- AG1 Auto Gain Control 1 data files | | | | |- AG2 Auto Gain Control 2 data files | | | | |- DP1 Doppler 1 data files | | | | |- DP2 Doppler 2 data files | | | | |- RNG Ranging data files | | | |-LEVEL2 | | |- CLOSED_LOOP | | | |-DSN | | | | |-DPS Doppler S-Band files | | | | |-DPX Doppler X-Band files | | | | | | | |-IFMS | | | | |-DP1 Doppler 1 data files | | | | |-DP2 Doppler 2 data files | | | | |-RNG Ranging data files | | | | | |- OPEN_LOOP | | | |-DSN | | | | |-DPS Doppler S-Band files | | | | |-DPX Doppler X-Band files | | | | |-BSR Bistatic radar power spectra | | | | |-SRG Bistatic radar surface reflection | | | | | geometry file | | | | | | | |-IFMS | | | | |-DP1 Doppler 1 data files | | | | |-DP2 Doppler 2 data files | | | | |-RNG Ranging data files Files in the DATA Directory --------------------------- Files in the DATA directory are: Data Level 1A: -------------- Level 1A data are incoming raw tracking data files obtained either from ESA IFMS or DSN. All incoming data files will be renamed after the file naming convention format defined in section 5.1 of the MaRS File Naming Convention document [MARSFNC2004] and get a minimal detached label file .LBL. The original file name of the incoming tracking data files will be stored in the according label file as SOURCE_PRODUCT_ID. These files have the file extension .RAW if ASCII and .DAT if binary files. TNF's are screened for 'bad' data points by the JPL Radio Metric Data Conditioning Team (RMDCT) before the files are processed to ODF's. The TNF's included in this archive, however, are the pre- screened versions. Tracking and Navigation Files (TNF Directory) --------------------------------------------- TNF's became available within a few hours of the completion of a Mars Express pass. Orbit Data Files ---------------- ODF's were typically issued daily throughout the MEX mission with weekend data being consolidated into a single file on Monday. Typical ODF's have sizes 15-50 kB. All ODFs in the NEV archive have 60 second sampling. For higher sampling rates, the user must resort to the (more primitive) TNF products. Radio Science Receiver Files (RSR Directory) -------------------------------------------- Each RSR generated a stream of packets which could be assembled into files of arbitrary length. It was decided, after some experimentation, that files containing about 300 MB were the largest that could be easily manipulated in the analysis computers available in 2003. With a small number of exceptions, this is the largest file size that will be found in the RSR directory. The open-loop (RSR) data in the archive have been assembled from individual records (packets) into files. They have not other- wise been processed. IFMS Data Level 1B: ------------------- Level 1B files are created from level 1A (raw tracking data) as edited ASCII formatted file. Three files are generated for each ESA IFMS Level 1A data file: Level 1B IFMS data file (extension .TAB) Level 1B IFMS configuration file (extension .CFG) Level 1B IFMS label file (extension .LBL) The label file contains the description of the .TAB as well as of the .CFG file. Up to eight files are generated for each DSN ODF Level 1A file: Level 1B ODF Doppler S-Band data file + label file Level 1B ODF Doppler X-Band data file + label file Level 1B ODF Ranging S-Band data file + label file Level 1B ODF Ranging X-Band data file + label file Cologne is processing IFMS and ODF data, Stanford University processes RSR data up to level 2 and forwards raw and processed data to Cologne for archiving. However, for RSR there will be no level 1B files. Data Level 2: ------------- Level 2 data are calibrated data after further processing. The file format is in ASCII. This data level can be used for further scientific interpretation. The keyword OBSERVATION_TYPE in the Level 2 data labels indicates which kind of measurement was done. Keyword values are: Occultation, Target Gravity, Global Gravity, Solar Conjunction, Bistatic Radar, Commissioning and Phobos Gravity. Commissioning covers the NEV, CR1 and partly MCO Mission Phase where no specific measurement was done but equip- ment on board the spacecraft and on ground station was tested. IFMS Level 2 input files: ------------------------- There may be several Doppler 1 X-Band files in level 1A which will be merged on level 2. The same is true for all other Doppler file type and Ranging X and S-Band files. Only files with continuous sequenced numbers (the file names are the same only the sequence number varies for these files) are merged together. Otherwise a new Level 02 data file is created (merging data files with a new sequence of files). The level 2 source_product_id however gives the RAW IFMS file names since the raw files are used for processing. But the content of the IFMS raw files are identical to the corresponding level 1A IFMS files in one data set, only the file name is different. And the source_product_id of the level 1A files gives the original raw IFMS files. In addition the level 1A files have almost the same file name as the corresponding level 2 files. The corresponding level 1A files can be found in DATA/LEVEL1A/CLOSED_LOOP/IFMS/DP1 for Doppler 1 files DATA/LEVEL1A/CLOSED_LOOP/IFMS/DP2 for Doppler 2 files DATA/LEVEL1A/CLOSED_LOOP/IFMS/RNG for Ranging files ---------------------------------------------------------- Example: M32ICL1L02_D1X_040931103_00.TAB is a level 2 Doppler 1 X-Band file in M32ICL1L02_D1X_040931103_00.LBL the following SOURCE_PRODUCT_ID is given: SOURCE_PRODUCT_ID : {NN11_MEX1_2004_093_OP_D1_110358_0000, NN11_MEX1_2004_093_OP_D1_110358_0001, NN11_MEX1_2004_093_OP_D1_110358_0002} which are the raw IFMS files. The corresponding Level 1A files can be found in DATA/LEVEL1A/CLOSED_LOOP/IFMS/DP1 Their names are: M32ICL1L1A_D1X_040931103_00.RAW M32ICL1L1A_D1X_040931103_01.RAW M32ICL1L1A_D1X_040931103_02.RAW and the corresponding label files give the source_product_id as: in the M32ICL1L1A_D1X_040931103_00.LBL file the source_product_id is given as: SOURCE_PRODUCT_ID : NN11_MEX1_2004_093_OP_D1_110358_0000 in the M32ICL1L1A_D1X_040931103_01.LBL file the source_product_id is given as: SOURCE_PRODUCT_ID : NN11_MEX1_2004_093_OP_D1_110358_0001 in the M32ICL1L1A_D1X_040931103_02.LBL file the source_product_id is given as: SOURCE_PRODUCT_ID : NN11_MEX1_2004_093_OP_D1_110358_0002 Note that in this example the three level 1A files were merged to one level 2 files. The file names of the level 1A files are almost identical to the level 2 file name with three differences: - L1A instead of L02 in the file name which tells the user that these are level 1A and level 2 files. - The two digit-sequence number at the end of the file can be different. - The level 1A files have file extension .RAW whereas level 2 files have file extension .TAB ---------------------------------------------------------- Other inputs for Doppler and Ranging files: ------------------------------------------- predicted orbit file (see EXTRAS/ANCILLARY/UNI_BW) Meteorological file (see CALIB/CLOSED_LOOP/IFMS/MET) AGC file (see DATA/1A or 1B/CLOSED_LOOP/AGC1 or AGC2) Spacecraft orbit SPICE kernels (see EXTRAS/ANCILLARY/SPICE can also be downloaded from ftp://ssols01.esac.esa.int/pub/data/SPICE/MEX/kernels) Calibration Documentation: -------------------------- For documentation about Doppler and Ranging Calibration please see in DOCUMENT/MRS_DOC/MEX_MRS_IGM_DS_3035 and MEX_MRS_IGM_DS_3036 For differential Doppler: ------------------------- If the processed level 2 file is for example Doppler 1 X-Band then information from IFMS raw Doppler 1 S-Band files which cover approximately the same time were used for processing as well. For Doppler 1 S-Band information from IFMS raw Doppler 1 X-Band files were used. Doppler 2 files were processed accordingly. In most cases on IFMS1 and IFMS2 X-Band data were recorded: The corresponding raw files' names start with NN11_ or NN12_. S-Band data were in most cases recorded at IFMS3. The corresponding raw files' names start with NN13_. If for some reason this configuration was changed this is indicated either at the beginning of this description or at the end in the anomaly report. For Ranging in addition are used: --------------------------------- Range calibration file (see CALIB/CLOSED_LOOP/IFMS/RCL) Klobuchar coefficients for Earth-Ionosphere calibration (can be downloaded from this site: http://www.aiub.unibe.ch/download/CODE/) The calibrated Doppler files contain observed IFMS sky frequency, X-band Doppler and S-band Doppler frequency shift, residual (computed using the predict file), and the differential Doppler. If only a single downlink frequency was used, a differen- tial Doppler cannot be computed and was set to -999.999999 in the output file. The level 2 ranging files contain the observed TWLT at X-band or S-band, the calibrated TWLT at X-band or S-band, the TWLT delay at X-band or S-band and the differential TWLT. If only one frequency was used, the differential TWLT is set to -99999.9. IFMS Level 2 output files: -------------------------- Level 2 IFMS data file (extension .TAB) Level 2 IFMS label file (extension .LBL) Level 2 IFMS log file (extension .LOG). The log files can be found in /EXTRAS/ANCILLARY/MRS/LOGFILES and contain information about the level 2 Doppler and Ranging data processing. ODF Level 2 input files: ------------------------ ODF Level 1B files Doppler and Range prediction file or Orbit reconstructed file Media calibration files The calibrated Doppler files contain observed IFMS Doppler expressed as X-band Doppler or S-band Doppler, residual and detrended X-band or S-band Doppler (computed using the predict file), the detrended differential Doppler. If only one single frequency was used, the differential Doppler will be set to -999.999999. The level 2 ranging file contains the observed Two-Way- Light-Time (TWLT) at X-band or S-band, the calibrated TWLT at X-band or S-band, the TWLT delay at X-band or S-band and the differential TWLT. If only one frequency was used, the differential TWLT is set to -99999.9. Other inputs for Doppler and Ranging files: ------------------------------------------- Predicted orbit file (see EXTRAS/ANCILLARY/UNI_BW) Meteorological file (see CALIB/CLOSED_LOOP/ODF/MET) Spacecraft orbit SPICE kernels (see EXTRAS/ANCILLARY/SPICE can also be downloaded from: ftp://ssols01.esac.esa.int/pub/data/SPICE/MEX/kernels) RSR Level 2 output files: ------------------------- DPS and DPX: ------------ The RSR samples were digitally filtered to reduce bandwidth; in the process they were also converted from 16-bit I and 16-bit Q complex integer samples to 64-bit I and 64-bit Q double precision complex floating point samples. The complex floating point samples were Fourier transformed and estimates made of the carrier amplitude and frequency and their uncertainties. The reconstructed spacecraft trajectory, planetary epheme- redes, records of uplink and downlink tuning, and other data were used to calculate the expected carrier frequency at the receiving antenna. The Level 2 products are tables of the observed amplitude, its uncertainty, the observed frequency, its uncertainty, and the difference between the observed and the expected frequency as a function of time. Separate tables have been created for each RSR. BSR and SRG: ------------ Bistatic Radar Spectra ------------------------------ SPC files were the calibrated output of partial processing of RSR data collected for bistatic radar. They were ASCII tables of power and cross-voltage spectra. All spectra for a single observation were collected in a single ASCII file. The Level 2 bistatic radar spectra (BSR) have been processed as follows: The RSR samples were converted from 16-bit I and 16-bit Q complex integer samples to 64-bit I and 64-bit Q double precision complex floating point samples. In the process they were digitally corrected for non-uniform spectral response of the receiving system. This was done by computing spectra from series of time samples and dividing each spectrum by the square root of a power spectrum computed from many minutes of noise. The amplitude of the samples was then adjusted so that power spectra in each receiver channel would have an amplitude proportional to kTsysB where k is Boltzmann's constant, Tsys is the receiver system temperature in Kelvin, and B is the width of one frequency bin (spectral resolution) in the power spectrum. Then the power spectra (e.g., XR*conj(XR)) and cross spectra e.g., XR*conj(XL)) were computed. SRG files summarize the observation for Rosetta bistatic radar (BSR) observations.Structure of CALIB Directory: Please note that the following description lists all possible subfolders. If however there is no data to fill some of these folders they will not be generated. |-CALIB | |-CALINFO.TXT text description of the directory contents | | | |-CLOSED_LOOP | | |-DSN | | | |-ION Ionospheric Calibration files | | | |-MET Meteo data files | | | |-TRO Tropospheric Calibration files | | |-IFMS | | | |-RCL Range Calibration data files | | | |-DCL Doppler Calibration data files | | | |-MET Meteo data files | | | |-OPEN_LOOP | | |-DSN | | | |-BCAL System temperature calibration files | | | |-SRF Surface Reflection Filter Files | | | | | |-IFMS | | | |-RCL Range Calibration data files | | | |-DCL Doppler Calibration data files | | | |-MET Meteo data files | | | |-UPLINK_FREQ_CORRECT Only present if the uplink frequency in one of the .RAW files was identified as wrong. The Folder includes files which indicate the wrong and corrected uplink frequency and their corresponding files. Files in the CALIB Directory ---------------------------- Files in the CALIB directory are: Calibration data files have in principle the same structure as normal data files. But they do not contain scientific data but rather reflect the behaviour of the system. These kind of data is typically recorded at New Norcia once for every tracking before the real measurement took place. For example: range calibration data contain the equipment propagation delay measurements before the tracking pass. Note: If the uplink frequency in one of the .RAW files was identified as wrong the folder UPLINK_FREQ_CORRECT will be generated. It tells the user which files were affected and where to find the corrected Level 2 data files. Closed loop IFMS Calib data level 1A: ------------------------------------- These Level 1A data are incoming raw tracking data files obtained from ESA IFMS. All incoming data files will be renamed after the file naming convention format defined in section 5.1 of the MaRS File Naming Convention document [MARSFNC2004] and get a minimal detached label file .LBL. The original file name of the incoming tracking data files will be stored in the according label file as SOURCE_PRODUCT_ID. These files have the file extension .RAW. Closed loop IFMS Calib data level 1B: ------------------------------------- IFMS Calib level 1B files are processed from level 1A (raw tracking data) into an edited ASCII formatted file. Three files are generated for each ESA IFMS Level 1A data file: Level 1B IFMS data file (extension .TAB) Level 1B IFMS configuration file (extension .CFG) Level 1B IFMS label file (extension .LBL) The label file contains the description of the .TAB as well as of the .CFG file. DSN METEO Files (MET directory) ------------------------------- DSN METEO files were produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. Files give weather calibration information for DSN complexes. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). METEO files were typically released weekly and contain all weather data for the complex since 1 January. Each METEO file is accompanied by a PDS label. The files grow at the rate of approximately 90 kB per month. DSN Ionosphere Calibration Files (ION Directory) ------------------------------------------------ Ionosphere Calibration files were produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. They docu- mented and predicted Earth ionospheric conditions. Global Ionosphere Map (GIM) software created daily maps from Global Positioning System (GPS) data. Each day, a final map was created for the UT day three days previously and a preliminary map was created for the UT day immediately before. Also created were predict maps a couple times a week by averaging recent 'normal' days. Then the software evaluated the maps at the spacecraft line-of-sight and fitted the results to a normalized polynomial versus time over each spacecraft pass. This was done for all three modes: final, preliminary, and predict. Then the software selected the best available cali- bration for each pass (in priority order final > preliminary > predict). An operator ran a plotting program to view all of the calibrations and overrode the default selections where desired. The mapping technique is described by [MANNUCCIETAL1998]. They are ASCII files of variable length records. Each record is delimited by an ASCII carriage-return line-feed pair (ASCII 13 followed by ASCII 10). ION files were usually released at one week intervals to cover a single month; only final files covering a full month are included in this archive. Each ION file is accompanied by a PDS minimal label. Typical file sizes are approximately 50 kB. Troposphere Calibration Files (TRO Directory) --------------------------------------------- Troposphere Calibration files were produced by the Tracking System Analytic Calibration (TSAC) Group at JPL. They docu- mented and predicted Earth tropospheric conditions and were based on measurements made using Global Positioning System (GPS) satellites. These are ASCII files of variable length records. Each record is delimited by an ASCII line-feed (ASCII 10). Surface Reflection Filter Files (SRF Directory) ----------------------------------------------- SRF files contain power spectra derived from noise measure- ments when the radio system was stable and there were no spacecraft signals in the passband. SRF's were derived sepa- rately for each receiver channel; but the fact that the spectral characteristics of each receiver depended almost entirely on digital signal processing meant that there was little practical difference among channels when sampling rates (output bandwidths) were the same and the SRF's were inter- changeable. SRF's were ASCII PDS SPECTRUM objects with attached labels. System Temperature Calibration Files (BCAL directory) ----------------------------------------------------- This table contains system temperature calibration results from Venus Express (VEX) bistatic radar experiments. For each receiver channel the table includes the best estimate of system temperature with the antenna pointed to zenith (either pre- or post-cal, or a combination of both), the associated noise diode temperature, and the system temperature at the mid-point of the bistatic (surface) observation. In general there is one set of four rows for each experiment - one for each receiver channel (X-band and S-band, right- and left-circular polarization). The table is cumulative, growing by four rows for each new observation.Browse Files (BROWSE Directory): Browse files may be composite PostScript files summarizing quick-look processing of raw RSR data. In that case each file has a name: rggttttL1A_BRO_yydddhhmm_00.AUX. Each file has a JPEG version with the same file name but extension .JPG. Both files are accompanied by a single detached label of the same file name but extension .LBL. Each PostScript file is sized to fit on a single 8-1/2x11 inch page. Each landscape format page includes four panels showing a histogram of raw data (12-bit) samples (upper left), one-minute average power spectra derived from the raw samples (upper right), one-second averages of raw sample power versus time (lower left), and an extract of the first few lines of the source RSR PDS label (lower right). BRO files may be helpful in quickly scanning data to determine which files are suitable for closer study. IFMS Browse plot files are only available as JPEG files. These plots are generated in order to check data quality of IFMS Level 2 closed-loop data. The name of the files are the same like the Level 2 data files except for the data type identifier which is set as sss:B1X,B1S,B2X,B2S if the source of the plots is a Doppler 1 X-Band, Doppler 1 S-Band, Doppler 2 X-Band or Doppler 2 S-Band file, and the extension will be .JPG.Ancillary Data: An extensive set of ancillary files is needed for proper analysis and interpretation of the radio data. These are organized in parallel directories and stored approximately chronologically. When a file type is not represented on a CD- volume, the corresponding directory has been omitted. Files in the EXTRAS/ANCILLARY Directory --------------------------------------- Files in the EXTRAS/ANCILLARY directory are: ESOC: Relevant DDS files to describe the observation geometry SPICE: Relevant SPICE Kernels to describe the observation geo- metry UNI_BW: Relevant PREDICT files from the Uni BW Munich MRS: Level 2 processing log files SUE: Ancillary Spive Kernels coming from NAIF |-SPICE: Spice Kernels were produced by the MEX Flight Dynamics Team, converted to IEEE binary format, and then distri- buted by the JPL Navigation and Ancillary Information Facility (NAIF). For more information on NAIF and SPICE see http://pds-naif.jpl.nasa.gov/ The original Spice Kernels were merged with the JPL DE405 planetary ephemeris and the ephemeredes of Phobos and Deimos for the same time interval. DSN: Ancillary files provided by Deep Space Network |-EOP: Earth Orientation Parameter Files | Earth Orientation Parameter files were produced by the | Time and Earth Motion Precision Observation (TEMPO) | Group at JPL. They documented and predicted Earth rota- | tion (rate and axis). These are ASCII files of variable | length records. Each record is delimited by an ASCII | line-feed (ASCII 10). | There are both 'long' and 'short' versions. The long | file covered past motion since about 1962 and a predic- | tion for about three months into the future; these files | have typical sizes of 1 MB. | The short file covered the most recent nine months of | past motion and a prediction for three months into the | future; these files are typically 30 kB. Each EOP file | is accompanied by a PDS minimal label. | |-OPT: Orbit Propagation and Timing Geometry File | Orbit Propagation and Time Generation files contain | estimates of event timing (e.g., equator crossings) that | depend on precise knowledge of the spacecraft orbit. | These are ASCII files of variable length records. Each | record is delimited by an ASCII carriage-return | (ASCII 13) line-feed (ASCII 10) pair. File names | have the form ydddeeeC.OPT where the file name compo- | nents are the same as for BCK files (above). | Each OPT file is accompanied by a PDS minimal label with | file name ydddeeeC.LBL. Typical files are based on | reconstructed spacecraft trajectories, cover a month of | operation, and have sizes less than 500 kB. | |-LIT: Light Time File | Light Time files give radio propagation time from the | spacecraft to Earth as a function of time. These are | ASCII files of fixed length records. Each record is | delimited by an ASCII carriage-return line-feed pair. | File names have the form ydddeeeC.LIT where the file | name components are the same as for DKF files. An LIT | file may cover more than 365 days; so eee may be a year | or more after yddd. Each LIT file is accompanied by a | PDS label. Typical file sizes are less than 1 MB.Software: Software for parsing, reducing, and analyzing data such as these has been developed at University of Cologne and Stanford University. Because such software must usually operate at the bit-level and is written for a narrow range of platforms, it is not suitable for general distribution. No software is included with this archival data set.Documents: The DOCUMENT directory contains the files that provide documen- tation and supplementary information to assist in understanding and using the data products on the volume.The files evolved as the mission progressed; users should refer to thefiles on the most recent (highest numbered) RSI Volume-ID for themost up-to-date information. Files on early volumes may be only'place-holders'.The above mentioned documents represent the maximum of available docu-ments, but need not to be present for every measurement. For IFMS(NNO) measurements, please refer mainly to MRS_DOC, for DSN measure-ments to DSN_DOC.Structure of the DOCUMENT directory:DOCUMENT | |- DOCINFO.TXT |- MEX_POINTING_MODE_DESC.TXT Description of pointing modes. | |- MRS_DOC | | | |- M32ESOCL1B_RCL_021202_00.PDF | | Group delay stability specification | | and measurements at New Norcia. | | | |- M32ESOCL1B_RCL_021202_00.ASC | | Group delay stability specification | | and measurements at New Norcia. | | | |- M32ESOCL1B_RCL_030522_00.PDF | | Range calibrations at New Norcia | | and Kourou. | | | |- M32ESOCL1B_RCL_030522_00.ASC | | Range calibrations at New Norcia | | and Kourou. | | | |- M32UNBWL1B_RCL_030801_00.PDF | | Transponder group velocities (in | | german). | | | |- M32UNBWL1B_RCL_030801_00.ASC | | Transponder group velocities (in | | english, translated). | | | |- MEX_MRS_IGM_IS_3019.PDF MaRS Data Archive Plan. | | | |- MEX_MRS_IGM_IS_3019.ASC MaRS Data Archive Plan. | | | |- MEX_MRS_IGM_IS_3016.PDF MaRS File Naming Convention. | | | |- MEX_MRS_IGM_IS_3016.ASC MaRS File Naming Convention. | | | |- MEX_MRS_IGM_IS_3016_APP_A.ASC | | MaRS File Naming Convention | | Appendix A: Example PDS labels | | | |- MEX_MRS_IGM_MA_3008.PDF MaRS User Manual. | | | |- MARS_OPS_LOGBOOK_17.PDF Status of all planned radio | | science operations in year 2017. | | | |- MEX_MRS_IGM_LI_3028.PDF List of MaRS Team members. | | | |- MEX_MRS_IGM_DS_3035.PDF IFMS Doppler Processing Software | | Documentation: Level 1a to Level | | 2. | | | |- MEX_MRS_IGM_DS_3036.PDF IFMS Ranging Processing Software | | Documentation: Level 1a to Level | | 2. | | | |- MEX_MRS_IGM_DS_3037.PDF ODF Processing and Calibration | | Software: Level 1a to Level 1b | | Software Design Specifications | | | |- MEX_MRS_IGM_DS_3038.PDF | | ODF Doppler Processing and Calibra- | | tion Software: Level 1b to Level 2 | | Software Design Specifications. | | | |- MEX_MRS_IGM_DS_3039.PDF | | Radio Science Predicted and Recon- | | structed Orbit and Planetary Con- | | stellation Data: Specifications | | | |- MEX_MRS_IGM_DS_3043.PDF | | ODF Ranging Processing and Calibra- | | tion Software: Level 1b to Level 2 | | Software Design Specifications | | | |- MEX_MRS_IGM_TN_3045.PDF | | Reference Systems and Techniques | | for Simulation and Prediction of | | atmospheric and ionospheric | | sounding measurements | | | |- MEX_MRS_IGM_DS_3046.PDF | | Radio Science Geometry and Position | Index Software Design | Specifications. | |- ESA_DOC | | | |- IFMS_OCCFTP.PDF Documentation of IFMS data format. | | | |- HGA_CALA.ASC Mars Express High-Gain Antenna | | (HGA) calibration information. | | | |- HGA_SBDA.PDF S-band antenna patterns measured in | | orthogonal planes. | | | |- HGA_XBDA.PDF X-band antenna patterns measured in | | orthogonal planes. | | | |- MEX_ESC_ID_5003_FDSICD.PDF | | File format description of ESOC | | Flight Dynamics files (ancillary | | files). | | | |- MEX_ESC_IF_5003_APPENDIX_C.PDF | | Documentation of DDS | | configuration. | | | |- MEX_ESC_IF_5003_APPENDIX_I.PDF | | Definition of XML-schema for the | | data delivery interface. | | | |- MEX_ESC_IF_5003_APPENDIX_H.PDF | | Description of content of ESOC | | Flight Dynamics files (ancillary | | files). | | | |- MEX_ESC_IF_5003.PDF Data delivery interface document. | | | |- SOP_RSSD_TN_010.pdf Planetary Science Data Archive | | Technical Note Geometry | | and Position Information | | | | | |- ESA_MEX_TN_4009.PDF Mars Express Archive Conventions | | |- DSN_DOC | | | | | |- DSN_ODF_TRK_2_18.PDF Documentation of Tracking System | | Interfaces and Orbit Data File | | Interface | | | |- DSN_DESIGN_HB.PDF/.ASC Technical information on current | | and near future configurations of | | the NASA Deep Space Network (DSN) | | (ASCII version). | | | |- DSN_DESIGN_HB.ASC Technical information on current | | and near future configurations of | | the NASA Deep Space Network (DSN) | | (PDF version). | | | |- JPL_D_16765_RSR.PDF Documentation of RSR data format. | | | |- LIT_SIS.HTM | | Software Interface Specification | | (SIS) for Light Time Files (LIT). | | This is an HTML file accompanied by | | label LIT_SIS.LBL. | | | | | |-M00DSN0L1A_DKF_yydddhhmm_vv.TXT | | (optional) The DSN Keyword File | | (DKF) is an ASCII file containing a | | table of time-ordered DSN | | configuration instructions. | | | | | |-M00DSN0L1A_SOE_yydddhhmm_vv.TXT | | (optional) The Sequence of Events | | (SOE) file was derived from | | materials provided by the MEX | | Project. It contains a summary of | | all events that were encountered | | during the measurement. | | | |-M00SUEL1A_ENB_yydddhhmm_vv.TXT | | (optional) Experimenter notes. | | | |-M00SUEL1A_HEA_yydddhhmm_vv.TXT | | (optional) DSN MEX Data Collection. | | | |-MggDSN0L1A_NMC_yydddhhmm_vv.TXT | | (optional) The NMC (Network Monitor | | and Control) Log contains all NMC | | messages and operator inputs | | | |-MggDSN0L1A_MFT_yydddhhmm_vv.TXT | | (optional) Mars Express Manifest | | file which lists the data files | | which were processed. | | | |- MEDIASIS.HTM Format and content description for | | Media Calibration files (ION and | | TRO). This file should be used in | | conjunction with TRK_2_23.TXT. This | | is an HTML file accompanied by | | label MEDIASIS.LBL. | | | | | |- MON0158.LBL (optional) Label file for the Deep Space | | Mission System Interface for | | Mission Monitor Data, a document | | describing 0158-Monitor data | | generated by the Monitor Interface | | Assembly of the Network Monitor and | | Control System. 0158-Monitor | | records are used to analyze the | | quality of the telecommunications | | link and to confirm events and | | configurations. The document is | | provided in three formats: | | | | MON0158.ASC Readable text (no figures, simplified tables) | | MON0158.DOC Microsoft Word format | | MON0158.PDF Adobe Acrobat Portable Document Format | | | | | |- OCCLOG**.TAB A summary listing of RSR files | | collected during MEX radio science | | test and experiments. Format and | | content of the file is described by | | its label OCCLOG**.LBL. ** | | represents the sequence number. | | | |- Ryddd.LBL (optional) Label file for an operations | | report: set of notes describing | | tests before and during radio | | science operations or the progress | | of an experiment itself. | | y represents the year, ddd the DOY. | | There are three versions of the | | text. | | | | Ryddd.ASC ASCII version of text | | Ryddd.DOC Microsoft Word version of text | | Ryddd.PDF Adobe Acrobat version of text | | | | | |-JPEG (optional) | | |-RydddSLx.JPG | | (S-Band left circular 60s power spectra for | | | measurement plots) | | |-RydddSRx.JPG | | (S-Band right circular 60s power spectra for | | | measurement plots) | | |-RydddXLx.JPG (X-Band left circular 60s power spectra for | | | measurement plots) | | |-RydddXRx.JPG | | | (X-Band right circular 60s power spectra for | | | measurement plots) | | |-Ryddd.DOC/ASC Word and ASCII-documents containing notes | | of experiment | | | | The JPEG folder contains a set of notes (mostly in | | tabular form) recording the progress of the Mars Express | | bistatic radar experiment and a set of plots showing | | normalized power spectra from each receiver channel when | | the surface echo was strongest. These are stored in this | | volume in the subfolder. | | | | | |- NMC_SIS.TXT Contents of Network Monitor and | | Control Log. | | | |- OPTG_SIS.TXT SIS for Orbit Propagation and | | Timing Geometr Files (OPT). | | | |- SRX.TXT SIS for surface reflection data | | types SRG (geometry), SRI (image), | | and SRT (table). It was written | | for Mars Global Surveyor products; | | only the SRG data type appears in | | the Mars Express archive. | | | |- SUE_DMP.LBL Label file for the Stanford | | University Element (SUE) Data | | Management Plan (DMP). There are | | two parts to the document: | | | | SUE_DMP.ASC ASCII version of the text | | SUE_DMP.DOC Microsoft Word version of the document | | | | | |- TNF_SIS.TXT SIS for radio metric tracking data | | delivered to navigation and radio | | science beginning in early 2003. | | This is a text-only version of the | | TRK-2-34 SIS, which was distributed | | to users in Word and PDF formats. | | | | | |- TRK_2_21.TXT SIS for the Earth Orientation | | Parameter (EOP) file, which | | contains data on rotation of the | | Earth. | | | |- TRK_2_23.TXT/DSN_MEDIA_CAL_TRK_2_23.PDF | | | | SIS for Media Calibration Files -- | | Ionosphere Calibration files (ION) | | and Troposphere Calibration files | | (TRO). | | | |- TRK_2_24.TXT/DSN_WEA_FORMAT_TRK_2_24.PDF | | | | SIS for Deep Space Network (DSN) | | Weather Files (WEA). The version | | included here is not current, but | | no replacement has been located.The documents are either in PDF-Format or are text files in ASCII withvariable length of characters per line. Each line is delimited with acarriage-return (ASCII 13) line-feed (ASCII 10) pair.Media/Format: The archival data set is written on CD-WO media using the WinOn CD Creation Software or Nero Burning Rom. The CD-WO volumes conform to ISO 9660 standards.More general description of radio science data: Closed-loop and Open-loop data:: There are in principle two different ways to record radio science data: Open-loop and closed-loop data. The CLOSED-LOOP system used a phase-lock loop in the receiver to track the downlink signal, reporting both amplitude and fre- quency at rates typically of 1-10 times per second. In the OPEN-LOOP system, the signal was simply converted to a baseband frequency range; the entire passband was sampled and recorded for later processing. Typical open-loop sampling rates for MEX were 2000 complex samples per second. CLOSED-LOOP data are efficient for characterizing slowly changing signals; OPEN-LOOP data (because of their much higher volume) are usually used when the signal is very dynamic - such as during an occultation or bistatic radar measurement. The data set includes four primary data types with respect to the two different ground station systems. These systems are on the one hand the ESA ground station in New Norcia, Australia (NNO) and the NASA Deep Space Network (DSN).CLOSED-LOOP data types: | |- ESA: Intermediate Frequency Modulation System (IFMS) | Closed-Loop (CL) | | In this data set file names of data recorded at the | New Norcia IFMS closed loop system start with the | string 'M32_ICL' | | IFMS CL consists of Doppler and Ranging data at | selected sample rates. The sample rate is usually | 1/s. | The only exception are occultation data where the | sample rate should be 10/s to get a good enough | vertical resolution of the atmosphere. | Ranging are only recorded for gravity measurements. | | Thus the IFMS closed loop has three recording | systems IFMS 1, IFMS 2 and IFMS 3 | The standard_data_product_id in the data label | specifies on which system the data was recorded. | | MaRS measurements are usually done in TWO-WAY | configuration: that is an uplink signal goes up | (This is usually X-BAND but the uplink signal can | also be S-Band) and the ground station receives a | dual frequency simultaneous and coherent downlink | signal. | | IFMS 1 is configured for the uplink signal. It | receives X-Band downlink if uplink was X-Band and | S-Band downlink if uplink was S-Band. | IFMS 2 acts at backup. | IFMS 3 records the second downlink signal. This is | usually S-Band. But can also be X-Band when the | uplink was S-Band. | From 20.12.04: | IFMS 1 D1 is fixed to a sample rate of 1/s | IFMS 1 D2 is on fixed to a sample rate of 1/10s | | In addition each Doppler recording system has also | two Doppler channels which can record simultaneous- | ly and act as an additional backup system. | Therefore for each IFMS system there should be at a | given time two Doppler files and two Auto Gain | Control files recorded. The file names of these | data contain the string '_D1' or '_D2' for Doppler | and '_G1' or '_G2' for Auto Gain control files and | they will be on different subfolders within the | data directory. See further down the description of | the DATA Directory. | | For these data files only X-Band ranging was | possible. Ranging data was nominally recorded on | IFMS1. | |- DSN: |-Tracking and Navigation File (TNF) | | The Tracking and Navigation File (TNF) is the primary out- | put from the DSN closed-loop receiver system. These are | large files, accumulating at the rate of approximately 3 | megabytes (MB) per hour of antenna operation. The files | comprise nearly 20 block types, each designed to carry | data of interest to a particular navigation, telecommuni- | cations, or science community. | The blocks are described by TNF_SIS.TXT in the | DOCUMENT/DSN_DOC directory. Fields include: | Uplink and downlink antenna numbers | Spacecraft number | Equipment identifiers, status flags, and calibration | values | Time tags and frequency bands | Transmitted and received phase and frequency | Transmitted and received ranging information | Noise levels, signal-to-noise ratios, and uncertain- | ties | |-Orbit Data Files (ODF) | | For many applications the TNF is too cumbersome. The ODF | is an edited and partially processed version of the TNF. | It is a smaller file, often issued in daily increments of | about 0.2 MB. It contains the most important information | (range and Doppler) | needed by spacecraft navigators and investigators | interested in determining gravitational fields of bodies | such as Mars. Each ODF is accompanied by a full PDS label | which describes both the content and format of the | associated file. ODF data fields include: | Narrowband spacecraft VLBI, Doppler mode (cycles) | Narrowband spacecraft VLBI, phase mode (cycles) | Narrowband quasar VLBI, Doppler mode (cycles) | Narrowband quasar VLBI, phase mode (cycles) | Wideband spacecraft VLBI (nanoseconds) | Wideband quasar VLBI (nanoseconds) | One-way Doppler (Hertz) | Two-way Doppler (Hertz) | Three-way Doppler (Hertz) | One-way total count phase (cycles) | Two-way total count phase (cycles) | Three-way total count phase (cycles) | PRA planetary operational discrete spectrum range (range | units) | SRA planetary operational discrete spectrum range (range | units) | RE(GSTDN) range (nanoseconds) | Azimuth angle (degrees) | Elevation angle (degrees) | Hour angle (degrees) | Declination angle (degrees) | | For more information please refer to document | [DSN_ODF_TRK-2-18] in the DOCUMENT/DSN_DOC folder.Open- Loop data types: | |-ESA: Intermediate Frequency Modulation System (IFMS) Open-Loop | (OL) | | During the commissioning phase the IFMS Open-Loop | recording system was not implemented, yet. | |-DSN: Radio- Science Receiver (RSR) | | The Radio Science Receiver (RSR) is a computer- | controlled open loop receiver that digitally records a | spacecraft signal through the use of an analog to | digital converter (ADC) and up to four digital filter | sub-channels. The digital samples from each | sub-channel are stored to disk in one second records | in real time. In near real time the one second records | are partitioned and formatted into a sequence of RSR | Standard Format Data Units (SFDUs) which are | transmitted to the Advanced Multi-Mission Operations | System (AMMOS) at the Jet Propulsion Laboratory (JPL). | Included in each RSR SFDU are the ancillary data | necessary to reconstruct the signal represented by the | recorded data samples. | | Each SFDU is defined here as a single row in a | PDS TABLE object; later SFDUs are later rows. The | first fields in each row contain the ancillary data | (time tags and frequency estimates, for example) that | applied while the samples at the end of the record | were being collected. The object definitions below | explain where the fields are and what the contents | represent. | | Analysis of variations in the amplitude, frequency, | and phase of the recorded signals provides information | on the ring structure, atmospheric density, magnetic | field, and charged particle environment of planets | which occult the spacecraft. Variations in the | recorded signal can also be used for detection of | gravitational waves. | | DSN open-loop receivers sample a narrow part of the micro- | wave spectrum near the spacecraft transmitting frequency. | For radio occultation tests, two RSR's were used - one | each for X-RCP and S-RCP with output sampled at rates of | 2000 (complex; 16-bit I, 16-bit Q). | The data were examined for compliance with data acquisi- | tion procedures and to measure the frequency/stability of | the radiolink. Four RSR's (X-RCP, S-RCP, X-LCP, and S-LCP) | each sample at a rate of 25000 (complex; 16-bit I, | 16-bit Q) to test bistatic radar data acquisition. | | Header information accompanying each RSR record included: | | Date and time of the first data sample | Sample rate and channel assignments | Receiver local oscillator phase and frequency | Attenuator settings | RMS voltages at several stages in the receiving chain | | | For more information please refer to document | [JPL_D-16765_RSR] in the DOCUMENT/DSN_DOC folder.
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