PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT INTERCHANGE_FORMAT = ASCII PUBLICATION_DATE = 2021-03-05 NOTE = "Introduction to this archive volume." END_OBJECT = TEXT Mars Express Radio-Science Data Archive Volume ID: MEXMRS_9101 Data from Occultation Season 07 in 2004 MEX Extended Mission V1.0 "MEXMRS_9101_V1.0" AAREADME.TXT 2021-03-05 Martin Paetzold Rheinisches Institut für Umweltforschung University of Cologne ============================================================================ INTRODUCTION ============================================================================ MaRS radio occultation observations are carried out during the occultation ingress, when the MEX spacecraft moves behind the planetary disk as seen from the Earth. MaRS occultation data usually cover two recording phases: the occultation ingress (1), the time when the spacecraft is occulted by the planet (2). The different observation phases can be distinguished regarding the signal strength of the received signal. In phase (1) the signal level is high compared to phase (2). In Phase (2) a drop of the signal strengtht is visible. For the derivation of Level 4 data profiles the ingress part of the occultation measurement was processed. ============================================================================ DATA SET INFORMATION ============================================================================ The diagram below shows the organization of the data set, starting from the root directory. root | |- AAREADME.TXT |- VOLDESC.CAT | |- CATALOG | |- CATINFO.TXT Streamlined PDS catalog files | |- MISSION.CAT for mission, host, instrument, | |- INSTHOST.CAT references, personnel, and | |- INST.CAT data set (files evolve as | |- REF.CAT mission progresses). | |- PERSON.CAT | |- DATASET.CAT | |- SOFT.CAT | | |- DATA | | | |- YYYY_DDD_XXXX | | |- LEVEL04 | | |- rggttttlll_sss_yydddhhmm_qq.eee | | (The description of the file name format can | | be found in section 2.3 and table 2.1 in | | DOCUMENT/MEX_MRS_RIU_IS_3050.PDF). | |- DOCUMENT | | | |- DOCINFO.TXT | | | |- MEX_MRS_RIU_IS_3050.PDF File naming convention for | | Higher Science Products. | | | |- MARS_DESC.TXT Description of the Mars | | Express Radio Science | | Experiment MaRS. | | | |- MEX-MRS-RIU-MA-3008.PDF Flight operations manual | | Experiment user manual. | | | |- MEX_POINTING_MODE_DESC.TXT MEX pointing mode | | description. | | | |- MEX_MRS_RIU_MP_001.TAB Mars Express Mission | | phases. | | | |- M00SUMMDSN_OC01_040930000_01.TXT Mars Express Summary for | | OCC1 (DSN). | | | |- M00SUMMNNO_OC01_040930000_01.TAB Mars Express Summary for OCC1 (NNO). | | | |- M00SUMMDSN_OC01_040930000_01.TAB Mars Express Summary for OCC1 (DSN). Data files ---------- All included files in this data set are in ASCII. 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 .LOG Additional processing information .TXT Information (text) files The files are named named after the file naming convention format, which can be found in section 2.3 and table 2.1 in DOCUMENT/MEX_MRS_RIU_IS_3050.PDF. Structure of DATA Directory =========================== The DATA folder contains one or more subfolder, which contains one measurement. The subfolder are named after the format YYYY_DDD_XXXX, where YYYY: Year DDD : Day of year XXXX: Volume-ID (The Vol-ID is the Radio Science Volume-Id and is not identical with the ESA PSA Volume-Id. It is incremented measurement by measurement, independent what kind of measurement was conducted. The Radio Science Volume-Id corresponds to the Volume-ID which is used in the Level 2 (PSA data level) DATA_SET_ID. It can also be found in the summary table file in the DOCUMENT directory.) |- DATA | | | |- YYYY_DDD_XXXX | | | | | |- rggttttlll_sss_yydddhhmm_qq.eee | | (The description of the file name format can be | | found in section 2.3 and table 2.1 in | | DOCUMENT/MEX_MRS_RIU_IS_3050.PDF) | | Files in the DATA Directory --------------------------- Please note that the following description lists all possible files. If however there is no data to fill some of these subfolders they will not be generated. Files in the DATA directory are: Ionospheric profiles: --------------------- IIX: Ionosphere electron density profile from X-band (Ingress) IID: Ionosphere electron density profile from diff. doppler data (Ingress) Neutral atmospheric profiles: ----------------------------- AIX: Neutral atmospheric profile from X-band (Ingress) Structure of DOCUMENT Directory =============================== |- DOCUMENT | | | |- DOCINFO.TXT | | | |- V00SUMML03_OC6_083040000_01.TAB Information on included data | | products. | | | |- MEX_MRS_RIU_IS_3050.PDF File naming convention for | | Higher Science Products. | | | |- MARS_DESC.TXT Description of the Mars | | Express Radio Science | | Experiment MaRS. | | | |- MEX-MRS-RIU-MA-3008.PDF Flight operations manual | | Experiment user manual. | | | |- MEX_POINTING_MODE_DESC.TXT MEX pointing mode | | description. | | | |- MEX_MRS_RIU_MP_001.TAB Mars Express Mission | | phases. Files in the DOCUMENT Directory ------------------------------- The DOCUMENT directory contains the files that provide documentation and supplementary information to assist in understanding and using the data products of the data set. 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'. 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. Software ======== Software for parsing, reducing, and analyzing data has been developed at the department Planetenforschung at Rheinisches Institut fuer Umweltforschung University of Cologne and at the 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. 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-locked loop in the receiver to track the downlink signal, reporting both amplitude and frequency at rates typically of 0.1-10 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 VEX were 100000 complex samples per second. CLOSED-LOOP data are efficient for characterizing slowly changing signals; OPEN-LOOP data (because of their much higher sample rate) are usually used when the signal is very dynamic - such as during an occultation or bistatic radar measurement. ACRONYMS ======== AAS Atmosphere Analysis Software AGC Automatic Gain Control AMMOS Advanced Multi-Mission Operations System ATDF Archival Tracking Data Files ADC Analog to Digital Converter BWG Beam Wave Guide ground station (DSN) CALI calibration file CHDO Compressed Header Data Object CVP Commissioning DDS Data Distribution System DSMS Deep Space Mission System DSN Deep Space Network ESA European Space Agency ENT/EXT Extended Mission EMP Extended Mission Phase ESOC European Space Operations Centre G/S Ground Station HEF High Efficiency ground station (DSN) IFMS Intermediate Frequency Modulation System JPL Jet Propulsion Laboratory MEX Mars Express MGS Mars Global Surveyor NEA NEAR NNO New Norcia Station (Perth) ODF Orbit Data File ODR Original Data Record PDS Planetary Data System PRM Prime Mission RO Rosetta Orbiter RSI Radio Science Investigation RSR Radio Science Receiver S/C Spacecraft SFDU Standard Formatted Data Unit TNF Tracking and Navigation File ULS Ulysses UniBw Universitaet der Bundeswehr in Muenchen MaRS Mars Express Radio Science Experiment