PDS_VERSION_ID = PDS3
RECORD_TYPE = FIXED_LENGTH
RECORD_BYTES = 178
FILE_RECORDS = 9716
INSTRUMENT_HOST_NAME = "MARS GLOBAL SURVEYOR"
TARGET_NAME = "MARS"
INSTRUMENT_NAME = "RADIO SCIENCE SUBSYSTEM"
DATA_SET_ID = "MGS-M-RSS-5-EDS-V1.0"
PRODUCT_ID = "ODR_OCCLOG.TAB"
PRODUCT_RELEASE_DATE = 2008-05-06
DESCRIPTION = "This file contains summary information for
MGS radio occultation opportunities between January 1998 and November 2001
when the primary data type was the Original Data Record (ODR) produced by
the DSCC Spectrum Processor (DSP); this table has 16 columns.
Columns include start/stop times for data acquisition, antenna number,
data acquisition mode flags, sample rate, bandwidth, bit resolution,
record length, number of records, maximum signal-to-noise ratio, ODR or
RSR file name, SOE file name, and comments. Columnar data and delimiters
require 176 bytes; these are followed by an ASCII carriage-return and
line-feed, making the total line length equal to 178 bytes.
Orbit numbers in the keywords immediately below (START_ORBIT_NUMBER and
STOP_ORBIT_NUMBER) as well as in the COMMENTS column of the tables
themselves reflect the MGS Project decision to reinitialize orbit numbers
to 1 at the beginning of the MGS Mapping Phase. In addition, the numbers
listed here may be slightly different from the numbers kept by the MGS
Project office; there were operational advantages for the Radio Science
Team to pair ingress and egress occultations and this sometimes led to a
discrepancy depending on when the Project-defined orbit number changed
relative to the occultations. The difference between official MGS orbit
numbers and the orbit numbers shown here should never be more than 1.
This file was produced by the Mars Global Surveyor Radio Science Team, under
the direction of G. Leonard Tyler."
START_TIME = 1998-01-24T19:15:36
STOP_TIME = 2001-11-15T18:09:45
START_ORBIT_NUMBER = 00001
STOP_ORBIT_NUMBER = 12024
PRODUCT_CREATION_TIME = 2008-05-06T20:40:00
PRODUCER_FULL_NAME = "RICHARD A. SIMPSON"
PRODUCER_INSTITUTION_NAME = "STANFORD UNIVERSITY"
PRODUCT_VERSION_TYPE = "PRELIMINARY"
PRODUCER_ID = "MGS RST"
^ODR_OCCLOG_TABLE = "ODR_OCCLOG.TAB"
OBJECT = ODR_OCCLOG_TABLE
NAME = "ODR OCCULTATION LOG"
ROWS = 9716
COLUMNS = 16
ROW_BYTES = 178
ROW_SUFFIX_BYTES = 0
INTERCHANGE_FORMAT = ASCII
DESCRIPTION = "This OCCLOG table contains a summary line
from each Original Data Record (ODR) radio occultation or test
opportunity. Each line contains 176 bytes of data followed by an ASCII
carriage-return line-feed pair. Character strings are enclosed by
double quotes, fields are delimited by commas; neither is counted in
defining either START_BYTE or BYTES."
OBJECT = COLUMN
NAME = "START TIME"
COLUMN_NUMBER = 1
DATA_TYPE = TIME
START_BYTE = 1
BYTES = 19
DESCRIPTION = "The date and time of the first ODR sample
in the data file. Format is YYYY-MM-DDThh:mm:ss
where
YYYY is the 4-digit year
MM is the 2-digit month
DD is the 2-digit day-of-month
hh is the 2-digit hour
mm is the 2-digit minute
ss is the 2-digit second
and time reference system is UTC. Time may be blank if no data were
collected."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "STOP TIME"
COLUMN_NUMBER = 2
DATA_TYPE = TIME
START_BYTE = 21
BYTES = 19
DESCRIPTION = "The date and time of the last integer
second time tag in the data file. Format is YYYY-MM-DDThh:mm:ss
where
YYYY is the 4-digit year
MM is the 2-digit month
DD is the 2-digit day-of-month
hh is the 2-digit hour
mm is the 2-digit minute
ss is the 2-digit second
and time reference system is UTC. May be blank or partly blank if no
data were collected."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "ANTENNA NUMBER"
COLUMN_NUMBER = 3
DATA_TYPE = ASCII_INTEGER
START_BYTE = 41
BYTES = 2
FORMAT = "I2"
DESCRIPTION = "The number of the DSN antenna used to
collect the open-loop data. 70-m antennas include DSS 14,
43, and 63; 34-m high-efficiency (HEF) antennas include DSS 15, 45, and
65. 34-m beam-waveguide (BWG) antennas include DSS 25, 34, and 54."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SAMPLE RATE"
COLUMN_NUMBER = 4
DATA_TYPE = ASCII_INTEGER
START_BYTE = 44
BYTES = 5
FORMAT = "I5"
UNIT = "SAMPLES PER SECOND"
DESCRIPTION = "The sampling rate for the channel(s) in
the data file. Real 8- or 12-bit samples were taken. Nominal rate
for MGS radio occultations was 5000 samples per second. Left blank or
set to 0 if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "FILTER BANDWIDTH"
COLUMN_NUMBER = 5
DATA_TYPE = ASCII_INTEGER
START_BYTE = 50
BYTES = 5
FORMAT = "I5"
UNIT = "HERTZ"
DESCRIPTION = "The 3 dB width of the bandwidth sampled.
Nominally 2000 Hertz, for the sampling rate of 5000 sps. Left blank or
set to 0 if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "DSP MODE"
COLUMN_NUMBER = 6
DATA_TYPE = ASCII_INTEGER
START_BYTE = 56
BYTES = 1
FORMAT = "I1"
UNIT = "N/A"
DESCRIPTION = "The mode selected for the DSCC Spectrum
Processor (DSP). Usually 2 for MGS radio occultations. Left blank or
set to 0 if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "BIT RESOLUTION"
COLUMN_NUMBER = 7
DATA_TYPE = ASCII_INTEGER
START_BYTE = 58
BYTES = 2
FORMAT = "I2"
UNIT = "N/A"
DESCRIPTION = "The number of bits in each sample.
Usually 12 for MGS radio occultations; 8 is the only other allowed
value. 12-bit samples were found to have 11-bit resolution in
practice. Left blank or set to 0 if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "RECORD LENGTH"
COLUMN_NUMBER = 8
DATA_TYPE = ASCII_INTEGER
START_BYTE = 61
BYTES = 5
FORMAT = "I5"
UNIT = "BYTE"
DESCRIPTION = "The number of bytes in each logical
record in the file. For nominal operations usually 1666 bytes of which
166 bytes were header and the remaining 1500 bytes contained 1000
12-bit data samples. Left blank or set to 0 if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "NUMBER OF RECORDS"
COLUMN_NUMBER = 9
DATA_TYPE = ASCII_INTEGER
START_BYTE = 67
BYTES = 6
FORMAT = "I6"
UNIT = "N/A"
DESCRIPTION = "The number of records in the file.
Number of records multiplied by the record length (Column 8) should
equal the file size in bytes. Left blank or set to 0 if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "NUMBER OF MISSING RECORDS"
COLUMN_NUMBER = 10
DATA_TYPE = ASCII_INTEGER
START_BYTE = 74
BYTES = 3
FORMAT = "I3"
UNIT = "N/A"
DESCRIPTION = "The number of records missing from the
file, as determined during quick-look processing. Based on gaps in
record numbers in the headers of each logical record. Duplicate records
are not counted here -- only records that are believed to be missing.
There was no attempt to repair files for either missing or duplicate
records. Left blank if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "MAXIMUM SIGNAL-TO-NOISE RATIO"
COLUMN_NUMBER = 11
DATA_TYPE = ASCII_REAL
START_BYTE = 78
BYTES = 5
FORMAT = "F5.1"
UNIT = "DECIBEL PER HERTZ"
DESCRIPTION = "The maximum carrier-to-noise level during
times when the spacecraft was not occulted by the planet. Based on 60-
second power spectra with 5 Hz resolution (typically), calculated by
program PREPLOOK. Left blank or set to 0 if no data."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SYSTEM TEMPERATURE"
COLUMN_NUMBER = 12
DATA_TYPE = ASCII_REAL
START_BYTE = 84
BYTES = 7
FORMAT = "F7.2"
UNIT = "KELVIN"
DESCRIPTION = "The system temperature of the open-loop
receiving system, read from displays at the Jet Propulsion Laboratory,
usually during ingress. Set to 0 or left blank if unknown."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "ODR FILE NAME"
COLUMN_NUMBER = 13
DATA_TYPE = CHARACTER
START_BYTE = 93
BYTES = 12
FORMAT = "A12"
UNIT = "N/A"
DESCRIPTION = "The name of the file containing DSP
records (headers plus data samples). Files have names of the form
YDDDhhmm.ODR
where
Y is the 1-digit year of the first data sample
DDD is the 3-digit day-of-year of the first data sample
hh is the 2-digit hour of the first data sample
mm is the 2-digit minute of the first data sample (in
cases where two files have the same YDDDhhmm
the second name is modified by converting the
second digit in mm to a letter.
Left blank if data acquisition was unsuccessful."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "SOE FILE NAME"
COLUMN_NUMBER = 14
DATA_TYPE = CHARACTER
START_BYTE = 108
BYTES = 16
FORMAT = "A16"
UNIT = "N/A"
DESCRIPTION = "The name of the controlling Sequence of
Events file when the data were collected. This is the original file
name, as it appeared in the MGS Central Data Base. Typical file names
had the form
mmNNNc.vv.tsoe
where
mm identifies this as a Mars Mapping SOE
NNN is the Mapping Cycle number
c is the planning version for the Mapping Cycle (a letter)
vv is the version of the SOE
SOE files in the MGS Radio Science Team server are renamed according to
to an 8.3 file naming convention. But it may be possible to search for
the original file name using either the MGS RST data base or index
files. Left blank if not known or if irrelevant (data acquisition was
not successful)."
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "QUALITY"
COLUMN_NUMBER = 15
DATA_TYPE = CHARACTER
START_BYTE = 127
BYTES = 3
FORMAT = "A3"
UNIT = "N/A"
DESCRIPTION = "Data quality indicator.
First character indicates expectation from observation:
A HGA, scheduled occultation; high-quality science expected
B Lower quality data expected (e.g., spacecraft using LGA)
C Non-occultation observation (e.g., USO test)
D Observation opportunity, but not scheduled
Second character indicates results:
0 No data, or data irreparably corrupted
1 Data badly corrupted; no present plan to attempt recovery
2 Seriously degraded data, from causes beyond control
(e.g., weather)
3 Seriously degraded data from causes associated with equipment
4 Minor degradations (SNR 6 dB low, frequency residuals,
missing records, baseline unstable, uplink ramping)
5 No known problems
Third character gives main cause for degradation (if any):
a all OK
b baseline unstable or too short
d DSP failure
e equipment failure (other than DSP or GDS)
f frequency instabilities/residuals
g data lost in ground data system (GDS)
m missing records
n low carrier-to-noise, or unstable noise level
o operator error
p POCA
r ripple (spectral or temporal)
s sawtooth frequency residual
t tuning or timing (orbit) problem
u spurs
w weather
x not applicable
y unknown
z multiple problems"
END_OBJECT = COLUMN
OBJECT = COLUMN
NAME = "COMMENTS"
COLUMN_NUMBER = 16
DATA_TYPE = CHARACTER
START_BYTE = 133
BYTES = 43
FORMAT = "A43"
UNIT = "N/A"
DESCRIPTION = "Terse comments, usually indicating the
number of the occultation or any problems with the data. Most comment
fields begin with
nnnnnx:m
where
nnnnn is the 5-digit orbit number, where orbit 1 was the
first orbit in the MGS Mapping phase
x denotes ingress (i) or egress (e)
m is a quality indicator for any observed surface echo
- no surface echo expected (e.g., test data)
0 none seen in processing to date
1 hint of a surface echo
2 weak but persistent surface echo
3 moderately strong, often with amplitude variations
4 very strong
5 extremely strong (among top 1 percent "
END_OBJECT = COLUMN
END_OBJECT = ODR_OCCLOG_TABLE
END
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