| 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 proposed see
the MaRS User Manual [MARSUSERMANUAL2004] in the MaRS
DOCUMENT/MRS_DOC folder.
This is a Commissioning measurement covering the time
2003-06-29T14:44:10.000 to 2003-06-30T00:56:13.000.
This data set was collected during the MEX Mission Near Earth
Verification Phase (NEV) - shortly after launch.
No specific measurement was done on this day but the configuration was
tested. Testing was done during the NEV, CR1 and partly MCO Mission phase.
During NEV several comissioning measurements were performed which
had to purpose to test the radio transponders and oscillator aboard
the space craft as well as the equipment at the ground stations mainly
at the new ESA ground station New Norcia (NNO).
For more information see INST.CAT or the MaRS User Manual
[MARSUSERMANUAL2004].
Overview of perfomed measurements:
DOY 180, 2003-06-29: Tracking at New Norcia performed in the so called
TWOD-X configuration. That is, X-Band uplink at IFMS 1 and X and S-Band
coherent and simultanous downlink. Doppler recording was performed
all the time.
-18:00 UTC: TM ON, Ranging ON
-19:45 UTC: TM OFF, Ranging OFF
-23:45 UTC: TM ON, Ranging ON
-01:00 UTC: End of operation
Data sample rate was 1/sec.
DOY 182, 2003-07-01: Tracking at New Norcia performed in the so called
TWOD-X configuration. That is, X-Band uplink at IFMS 2 and X and S-Band
coherent and simultanous downlink. Doppler recording was performed
all the time.
-18:00 UTC: TM ON, Ranging ON
-19:05 UTC: TM OFF, Ranging OFF
-23:05 UTC: TM ON, Ranging ON
-00:05 UTC: End of operation
Data sample rate was 1/sec.
DOY 183, 2003-07-02: Tracking at New Norcia performed in the so called
TWOD-S configuration. That is, S-Band uplink at IFMS 1 and X and S-Band
coherent and simultanous downlink. Doppler recording was performed
all the time.
-18:20 UTC: TM ON, Ranging ON
-19:20 UTC: TM OFF, Ranging OFF
-23:30 UTC: TM ON, Ranging ON
-01:20 UTC: End of operation
Data sample rate was 1/sec.
DOY 187, 2003-07-06: Parallel tracking pass at Deep Space Network (DSN)
station DSS 43 (70 meter station also uplinking) and New Norcia (only
listening). Space craft was in ONED mode that is uplink was switched off
during operation. But there was X-and S-Band downlink. Doppler recording
was performed all the time.
Data recording at DSN: TNF (closed loop) and RSR (open loop) data.
Data recording at NNO: Doppler, Meteo, Auto Gain Control and Ranging
files at a sample rate of 1/sec.
-15:00 UTC: Space craft is in TWOD-X configuration, TM ON, Ranging ON
-16:00 UTC: Begin of ONED activity, Ranging off, TM ON (??)
-17:05 UTC: TM OFF and Ranging OFF
-19:08 UTC: TM ON
-20:07 UTC: X-Band Uplink up. End of ONED, begin of normal TWOD-X.
Ranging ON
-21:08 UTC: End of activity
Two-way Ranging and Doppler recordings were done before and after the
ONED activity.
DOY 191, 2003-07-10: Parallel tracking pass at Deep Space Network (DSN)
station DSS 43 (70 meter station also uplinking) and New Norcia (only
listening). Space craft was in ONES-X mode that is uplink was switched
off during operation. Only X-Band downlink. Doppler recording was
performed all the time.
Data recording at DSN: TNF (closed loop) and RSR (open loop) data.
Data recording at NNO: Doppler, Meteo, Auto Gain Control and Ranging
files at a sample rate of 1/sec.
-13:15 UTC: Begin of activity, Ranging ON, TM ON, space craft was
in TWOS mode (X-Band up- and downlink)
-14:02 UTC: Uplink was dropped, TM ON, spacecraft in ONES-X mode.
-14:25 UTC: Begin of track at New Norcia, Begin of measurements at NNO,
TM ON
-15:05 UTC: TM OFF
-17:06 UTC: TM ON
-18:11 UTC: X-Band Uplink up. End of ONES, begin of normal TWOS.
Ranging ON, TM ON
-19:16 UTC: End of activity
DOY 192, 2003-07-11: Tracking at DSN at the Goldstone complex in the
TWOD-S mode. That is, S-Band uplink at IFMS 1 and X and S-Band coherent
and simultanous downlink. Doppler recording was performed all the times.
- 18:30 UTC: TM ON, Ranging ON
- 19:45 UTC: TM OFF, Ranging OFF
- 23:45 UTC: TM ON, Ranging ON
- 00:55 UTC: End of activity.
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, Venus Express and Rosetta.
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 Comissioning | MCO | 2003-12-26 - 2004-06-30
----------------------------------------------------------------
Prime Mission | PRM | 2004-07-01 - 2005-11-30
----------------------------------------------------------------
Extended Mission | ENT | TBD
----------------------------------------------------------------
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 station New Norcia. Level 1a to level 2 data are archived.
The predicted and reconstructed Doppler and range files
Geometry files
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)
--------------------------------------------------------
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 number in 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 volume.
It looks something like:
XXXXXX-ZZZZ
Acronym | Description | Example
--------------------------------------------------------
XXXXXX | Mission and Instrument ID | MEXMRS
--------------------------------------------------------
ZZZZ | 4 digit sequence number | 0123
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 Anxiliary files (event files, attitude files,
ESOC orbit files, products, SPICE files)
.TXT Information (text) files
File 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 according 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 |
-------------------------------------------------------------
gg | Ground station ID: | 43
| |
| 00: valid for all ground stations |
| |
| DSN complex Canberra: |
| --------------------- |
| 34 = 34 m BWG (beam waveguide) |
| 43 = 70 m |
| 45 = 34 m HEF (high efficiency) |
| |
| ESA Cebreros antenna: |
| --------------------- |
| TBD = 35 m |
| |
| DSN complex Goldstone: |
| ---------------------- |
| 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: |
| ------------------- |
| TBD = 15 m |
| |
| DSN complex Madrid: |
| ------------------- |
| 54 = 34 m BWG |
| 55 = 34 m BWG |
| 63 = 70 m |
| 65 = 34 m HEF |
| |
| ESA New Norcia antenna: |
| ----------------------- |
| 32 = 35 m |
-------------------------------------------------------------
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 |
| |
| Level 2: |
| ------- |
| UNBW = predicted and reconstructed |
| Doppler and range files |
| IFMS = ESA IFMS files |
| ODF0 = DSN ODF closed loop file |
| T000-T017 = TNF closed loop file |
| RSR0 = DSN RSR open loop file |
| NAIF = JPL or ESTEC SPICE Kernels |
| GEOM = geometry file |
| |
--------|------------------------------------------|--------
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 & 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 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) |
| BRO bistatic radar 4-panel plots (browse)|
| |
| ESOC ancillary data level 1A: |
| ----------------------------- |
| ATR attitude file, reconstrucetd |
| EVT orbit event file |
| OHC orbit file, heliocentric cruise |
| OMO orbit file, marscentric, operational |
| |
| DSN ancillary data level 1A: |
| ----------------------------- |
| DKF DSN Keyword File |
| MON DSN monitor data |
| NMC DSN Network Monitoring Control file |
| SOE DSN Sequence of Events |
| TRO DSN tropospheric calibration model |
| MET DSN meteorological file |
| ION DSN ionosheric calibration model |
| |
| 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 ancillary data level 1B: |
| ----------------------------- |
| MET meteorlogical file |
| |
| 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 |
| BSR bistatic radar power spectra |
| SRG bistatic radar surface reflection |
| geometry file |
| |
| 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 attititude kernel file |
| PCK planetary constant kernel |
| SCK space craft clock kernel |
| TLS leap second kernel file |
--------|------------------------------------------|--------
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 twoway 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) |
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
| | |
| | |-------IFMS
| | | |
| | | |-----AG1 Auto Gain Control 1 files
| | | |
| | | |-----AG2 Auto Gain Control 2 files
| | | |
| | | |-----DP1 Doppler 1 data files
| | | |
| | | |-----DP2 Doppler 2 data files
| | | |
| | | |-----RNG Ranging files
| | |
| | |-------DSN
| | | |
| | | |-----ODF Orbit Data files
| | | |-----TNF Tracking Navigation Files
| |
| |-----OPEN_LOOP
| | |
| | |-------IFMS
| | |
| | |-------DSN
| |
| |-------RSR Radio Science Receiver Data files
|
|----LEVEL1B
|
| |
| |-----CLOSED_LOOP
| | |
| | |-------IFMS
| | | |
| | | |-----AG1 Auto Gain Control 1 files
| | | |
| | | |-----AG2 Auto Gain Control 2 files
| | | |
| | | |-----DP1 Doppler 1 data files
| | | |
| | | |-----DP2 Doppler 2 data files
| | | |
| | | |-----RNG Ranging files
| | |
| | |-------DSN
| | | |
| | | |-----ODF Orbit Data files
| |
| |-----OPEN_LOOP
| | |
| | |-------IFMS
| |
| |
| |
| |
|
|----LEVEL2
| |
| |-----CLOSED_LOOP
| | |
| | |-------IFMS
| | | |
| | | |
| | | |-----DP1 Calibrated Doppler 1 data files
| | | |
| | | |-----DP2 Calibrated Doppler 2 data files
| | | |
| | | |-----RNG Calibrated Ranging files
| | |
| | |-------DSN
| | | |
| | | |-----ODF Orbit Data files
| |
| |-----OPEN_LOOP
| | |
| | |-------IFMS
| | |
| | |-------DSN
| | | |
| | | |-----RSR Radio Science Receiver 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 4.1 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.
Data Level 1b:
--------------
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.
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 equipment 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 continous 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_prodict_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/L1A/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://solarsystem.estec.esa.nl/pub/projects/MEX/data/spice )
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 differential
Doppler cannot be computed and was set to zero 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 zero.
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 logfiles 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 zero.
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 zero.
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 directory content
|----- UPLINK_FREQ_CORRECT
| This folder will only be generated if the
| uplink frequency in one of the .RAW
| files was identified as wrong.
| It tells the user which files were
| affected and where to find the corrected
| Level 2 data files.
|
|------CLOSED_LOOP
| |
| |------IFMS
| | |
| | |----RCL Ranging Calibration Data Files level 1a&1b
| | |
| | |----FCL Doppler Calibration Data Files level 1a&1b
| | |
| | |----MET Meteo Files
| |
| |------DSN
|
|------OPEN_LOOP
| |
| |------IFMS
| |
| |------DSN
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 4.1 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.
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-WO 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 geometry
UNI_BW: Relevant PREDICT files from the Uni BW Munich
MRS: Level 2 processing logfiles
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 documentation 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 the
files on the most recent (highest numbered) archive volume for the most
up-to-date information. Files on early volumes may be only 'place-holders.'
Structure of the DOCUMENT directory:
DOCUMENT
|
|- DOCINFO.TXT Specifies the content of the
| document directory
|- MRS_DOC
| |
| |- M32ESOCL1B_RCL_021202_00.PDF Group delay stability specification
| | and measurements at New Norcia.
| |
| |- M32ESOCL1B_RCL_030522_00.PDF Range calibrations at New Norcia
| | and Kourou.
| |
| |- M32UNBWL1B_RCL_030801_00.PDF Transponder group velocities (in
| | german).
| |
| |- MEX-MRS-IGM-IS-3019.PDF MaRS Data Archive Plan.
| | MEX-MRS-IGM-IS-3019.ASC
| |
| |
| |- MEX-MRS-IGM-IS-3016.PDF MaRS File Naming Convention.
| | MEX-MRS-IGM-IS-3016.ASC
| |
| |
| |- MEX-MRS-IGM-MA-3008.PDF MaRS User Manual.
| |
| |
| |
| |- MARS_OPS_LOGBOOK_04_COM.PDF Status of all planned comissioning
| | radio science operations until
| | 2004-01-23
| |
| |- MEX-MRS-IGM-LI-3028.PDF
| |
| | List of MaRS Team members.
| |
| |- MEX_MRS_IGM_DS_3035.PDF
| |
| | IFMS Doppler Processing and
| | Calibration Software
| | Documentation: Level 1a to Level 2.
| |
| |- MEX_MRS_IGM_DS_3036.PDF
| |
| | IFMS Ranging Processing and
| | Calibration Software
| | Documentation: Level 1a to Level 2.
| |
| |- MEX-MRS-IGM-DS-3039.PDF Radio Science Predicted and Recon-
| | structed Orbit and Planetary Con-
| | stellation Data: Specifications
| |
| |- MEX-MRS-IGM-TN-3045.PDF Reference Systems and Techniques
| for Simulation and Prediction of
| atmospheric and ionospheric
| sounding measurements
| |
|- ESA_DOC
| |
| |- IFMS-OCCFTP_10_3_1.PDF Documentation of IFMS data format.
| |
| |- 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.
| |
| |- RO-EST-IF-5010_D15.PDF Specifications of operational
| interfaces and procedures.
|
|- DSN_DOC
| |
| |- DSN_WEA_FORMAT_TRK_2_24.PDF Specification of DSN weather file.
| |
| |- DSN_ODF_TRK-2-18.PDF Documentation of Tracking System
| | Interfaces and Orbit Data File
| | Interface
| |
| |- DSN_MEDIA_CAL_TRK_2_23.PDF Specifiaction of DSN media
| | calibration data.
| |
| |- JPL_D-16765_RSR.PDF Documentation of RSR data format.
|
The documents are either in PDF-Format or are text files in ASCII with
variable length of characters per line. Each line is delimited with a
carriage-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 frequency 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 usally X-BAND but the uplink signal can also
be S-Band) and the ground station receives a dual
frequency simultanous 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.
In addition each Doppler recording system has also
two Doppler channels which can record simultanously
and act as an additional backup system.
Therefor 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.
During the MCO phase only X-Band ranging was possible.
Ranging data was nominally recorded on IFMS1.
DSN: Orbit Data Files (ODF)
ODFs are edited versions of the Tracking and
Navigation Files (TNFs) the most primitive (and most
voluminous) product of the closed-loop system,
specifically targeted to spacecraft navigators and
scientists interested in gravity fields. ODF consists
of Range and Doppler Data and additional ancillary
data.
For more information please refer to document
[DSNTRK-2-18] in the DOCUMENT/DSN_DOC
folder.
Open- Loop data types:
ESA: Intermediate Frequency Modulation System (IFMS) Open-Loop (OL)
During the comissioning 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.
For more information please refer to document
[JPLD-16765] in the DOCUMENT/DSN_DOC folder.
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