urn:nasa:pds:radiosci.documentation:dsn.trk-2-18:odf07155
1.1
Example Radio Science Orbit Data File (ODF) from MESSENGER
1.16.0.0
Product_Observational
Verma, A. K.; Perry, M. E.; Lemoine, F. G.; Smith, D. E.; Ensor, S.; Reid, M. R.
2019
MESSENGER Radio Science Orbit Data File from Venus Flyby 2
2021-08-25
1.1
Updated to IM v1.16.0.0.
2020-05-02
1.0
Data migrated from PDS3 to be used as an example for illustrating how to extract
values from a binary Orbit Data File.
2007-06-04T10:00:39Z
2007-06-05T21:00:41Z
Science
Raw
MESSENGER raw radio tracking data
MErcury Surface, Space ENvironment, GEochemistry, and Ranging Mission
Mission
urn:nasa:pds:context:investigation:mission.messenger
data_to_investigation
MESSENGER
Host
urn:nasa:pds:context:instrument_host:spacecraft.mess
is_instrument_host
RSS
Instrument
urn:nasa:pds:context:instrument:rss.mess
is_instrument
Mercury
Planet
urn:nasa:pds:context:target:planet.mercury
data_to_target
JPL/DSN Document 820-013, TRK-2-18, Tracking System Interfaces, Orbit Data File Interface,
Originally issued 1983-06-15. Revision E issued 2008-02-29.
This Software Interface Specification (SIS) describes the content and format of DSN Orbit
Data Files (ODFs), which are produced by the NASA/JPL Multi-Mission Navigation Radio
Metric Data Conditioning Team for use in determining spacecraft trajectories, gravity
fields affecting them, and radio propagation conditions.
MESS-V/H-RSS-1-EDR-RAWDATA-V1.0:MESS_RS_07155_156_60S_ODF
data_to_raw_source_product
PDS/PPI
odf07155.dat
2018-10-18T10:03:16
88704
36c4097bbc449693ca7e4e0b758a5ddb
ODF File Label Group Header
0
1
The File Label Group
is usually the first of several groups of records in
an Orbit Data File (ODF). It identifies the spacecraft,
the file creation time, the hardware, and the software
associated with the ODF. The File Label Group Header
is the first record in the File Label Group. It is one
36-byte record and is followed by one 36-byte data
record. Occasionally, the File Label Group is omitted
from an ODF. The row suffix bytes in the File Label
Group Header are set to 0.
4
1
36
Primary Key
1
1
SignedMSB4
4
Item 1: The Primary Key indicates the type of data records to
follow. In the File Label Group Header this field is set to 101.
Secondary Key
2
5
UnsignedMSB4
4
Item 2: The Secondary Key is not used in the ODF. It is set to 0.
Logical Record Length (in packets)
3
9
UnsignedMSB4
4
Item 3: The Logical Record Length gives the
number of 36-byte physical records making up each logical
record in a File Label Group data record. For the File Label
Group it is set to 1.
Group Start Packet Number
4
13
UnsignedMSB4
4
Item 4: The Group Start Packet Number
gives the number of the ODF packet containing the File
Label Group Header. Set to 0, since the File Label Group
Header, when it appears, is always first.
Items 5-9
5
1
0
17
20
Suffix Bytes
1
1
UnsignedMSB4
4
The bytes to fill the record; set to 0.
ODF File Label Group Data
36
1
The File Label Group
is usually the first of several groups of records in
an Orbit Data File (ODF). It identifies the spacecraft,
the file creation time, the hardware, and the software
associated with the ODF. The File Label Group data
record is the second record in the File Label Group. It
is one 36-byte record and is preceded by one 36-byte
File Label Group header record. Occasionally, the File
Label Group is omitted from an ODF.
7
0
36
System ID
1
1
ASCII_String
8
Items 1: A character string identifying
the hardware on which the ODF was created.
Left-justified and padded with blanks.
Program ID
2
9
ASCII_String
8
Items 2: A character string identifying
the program under which the ODF was created.
Left-justified and padded with blanks.
Spacecraft ID Number
3
17
UnsignedMSB4
4
Item 3: ID number for the spacecraft. These
are specified in DSN document 820-013, OPS-6-21.
Representative values include
Magellan 18
Voyager 1 31
Voyager 2 32
Clementine 64
Galileo Orbiter 77
Mars Global Surveyor 94
MESSENGER 236.
File Creation Date (YYMMDD)
4
21
UnsignedMSB4
4
Item 4: The date on which the ODF was
created, given as a single number of the form YYMMDD.
where
YY is the two least significant digits of the year
MM is the month (01 through 12)
DD is the day of month (01 through 31).
File Creation Time (hhmmss)
5
25
UnsignedMSB4
4
Item 5: The time at which the ODF was
created, given as a single number of the form HHMMSS.
where
HH is the two-digit hour (00 through 23)
MM is the two-digit minute (00 through 59)
SS is the two-digit second (00 through 59).
File Reference Date (YYYYMMDD)
6
29
UnsignedMSB4
4
Item 6: The reference date for ODF
time tags -- for example, 19500101
for EME50. Older files which have
reference dates of zero will be
assumed to be EME50.
File Reference Time (HHMMSS)
7
33
UnsignedMSB4
4
Item 7: The reference time for ODF
time tags in the format HHMMSS.
ODF Identifier Group Header
72
1
The Identifier Group
is usually the second of several groups of records in
an Orbit Data File (ODF). It is sometimes used to
identify contents of data records that follow. The
Identifier Group Header is the first record in the
Identifier Group. It is one 36-byte record and is
followed by one 36-byte Identifier Group data record.
Occasionally the Identifier Group is omitted from an
ODF. The row suffix bytes in the Identifier Group
Header are set to 0."
4
1
36
Primary Key
1
1
SignedMSB4
4
Item 1: The Primary Key indicates the type of data records to
follow. In the Identifier Group Header this field is set to 107.
Secondary Key
2
5
UnsignedMSB4
4
Item 2: The Secondary Key is not used in the ODF. It is set to 0.
Logical Record Length (in packets)
3
9
UnsignedMSB4
4
Item 3: The Logical Record Length gives the
number of 36-byte physical records making up each logical
record in an Identifier Group data record. For the
Identifier Group it is set to 1.
Group Start Packet Number
4
13
UnsignedMSB4
4
Item 4: The Group Start Packet Number
gives the number of the ODF packet containing the
Identifier Group Header. Usually set to 2, since the
Identifier Group usually follows the Label Group
immediately in the ODF.
Items 5-9
5
1
0
17
20
Suffix Bytes
1
1
UnsignedMSB4
4
The bytes to fill the record; set to 0.
ODF Identifier Group Data
108
1
The Identifier Group
is usually the second of several groups of records in
an Orbit Data File (ODF). It is sometimes used to
identify contents of data records that follow. The
Identifier Group data record is the second record in
the Identifier Group. It is one 36-byte record and is
preceded by one 36-byte Identifier Group header record.
Occasionally the Identifier Group is omitted from an
ODF.
3
0
36
Identifier 1
1
1
ASCII_String
8
Items 1: A character string sometimes used to
identify contents of data records to follow. Set to the
ASCII characters 'TIMETAG' followed by one ASCII 'blank'.
Identifier 2
2
9
ASCII_String
8
Items 2: A character string sometimes used to
identify contents of data records to follow. Set to the
ASCII characters 'OBSRVBL' followed by one ASCII 'blank'.
Identifier 3
3
17
ASCII_String
20
Item 3: A character string sometimes used to
identify contents of data records to follow. Set to the
ASCII characters 'OD-SAMPL-ID FRQ RSD' followed by one ASCII blank.
ODF Orbit Data Group Header
144
1
The Orbit Data Group
is usually the third of several groups of records in an
Orbit Data File (ODF). It contains the majority of the
data included in the file. The Orbit Data Group Header
is the first record in the Orbit Data Group; it is
usually followed by many Orbit Data Group data records,
ordered by time. All records in the Orbit Data Group
have 36 bytes. The row suffix bytes in the Orbit Data
Group Header are set to 0. This Orbit Data Group
follows TRK-2-18, Revision E of 29 February 2008.
4
1
36
Primary Key
1
1
SignedMSB4
4
Item 1: The Primary Key indicates the
type of data records to follow. In the Orbit Data
Group Header this field is set to 109.
Secondary Key
2
5
UnsignedMSB4
4
Item 2: The Secondary Key is not used in the ODF. It is set to 0.
Logical Record Length (in packets)
3
9
UnsignedMSB4
4
Item 3: The Logical Record Length gives the
number of 36-byte physical records making up each logical
record in an Orbit Data Group data record. For the Orbit
Data Group it is set to 1.
Group Start Packet Number
4
13
UnsignedMSB4
4
Item 4: The Group Start Packet Number
gives the number of the ODF packet containing the
Orbit Data Group Header. Since the Orbit Data Group
usually follows immediately after the File Label Group
and the Identifier Group, it is usually set to 4.
Items 5-9
5
1
0
17
20
Suffix Bytes
1
1
UnsignedMSB4
4
The bytes to fill the record; set to 0.
ODF Orbit Data Group Data
180
2228
The Orbit Data Group
is usually the third of several groups of records in an
Orbit Data File (ODF). It contains the majority of the
data included in the file. The Orbit Data Group Header
is the first record in the Orbit Data Group; it is
usually followed by many Orbit Data Group data records,
ordered by time. All records in the Orbit Data Group
have 36 bytes. Their format and content follow the
specification in TRK-2-18, Revision E of 29 February 2008.
7
0
36
Record Time Tag, integer part
1
1
UnsignedMSB4
4
Item 1: The integer part of the record
time tag in seconds, measured from the File Reference Date and Time
in the ODF File Label Group Data (usually 0 hours UTC on 1 January 1950).
The fractional part of the time tag is in the next Field_Binary.
Items 2-3
2
5
UnsignedBitString
4
Items 2-3 of the ODF Orbit Data Group Data.
2
Record Time Tag, fractional part
1
1
10
UnsignedBitString
Item 2: The fractional part of the record
time tag (see Item 1) in milliseconds.
Primary Receiving Station Downlink Delay
2
11
32
UnsignedBitString
Item 3: Downlink delay for the primary
receiving station in nanoseconds.
Observable, integer part
3
9
SignedMSB4
4
Item 4: The integer part of the observable.
The fractional part is in Field 4 (Item 5). See Item
10 for the data type stored in these fields.
A Doppler observable (in Hertz) is computed according
to the following equation. The time tag tr is the
mid-point of the compression interval ti to tj.
Observable = [B/|B|]*[(Nj-Ni)/(tj-ti) - |Fb*K + B|]
where:
B = bias placed on receiver
Ni = Doppler count at time ti
Nj = Doppler count at time tj
ti = start time of interval
tj = end time of interval
K = spacecraft transponder turnaround ratio, which varies
with band used (see Item 11); set to
1 for S-band receivers
11/3 for X-band receivers
176/27 for Ku-band receivers
209/15 for Ka-band receivers
(Note: future spacecraft transponders may
require different values of K)
Fb = (X1/X2)*(X3*Fr + X4)
-Fsc + R3 for one-way Doppler
= (X1/X2)*(X3*Fr + X4)
-(T1/T2)*(T3*Ft + T4) for all other Doppler
where:
Fr = receiver (VCO) frequency at time tr
Fsc = spacecraft (beacon) frequency
Ft = transmitter frequency at time tr-RTLT
R3 = 0 for S-band receivers
= 0 for X-band receivers
= 0 for Ku-band receivers
= 0 for Ka-band receivers
T1 = 240 for S-band transmitters (see Item 12)
= 240 for X-band transmitters
= 142 for Ku-band transmitters
= 14 for Ka-band transmitters
T2 = 221 for S-band transmitters
= 749 for X-band transmitters
= 153 for Ku-band transmitters
= 15 for Ka-band transmitters
T3 = 96 for S-band transmitters
= 32 for X-band transmitters
= 1000 for Ku-band transmitters
= 1000 for Ka-band transmitters
T4 = 0 for S-band transmitters
= 6.5 10^9 for X-band transmitters
= -7.0 10^9 for Ku-band transmitters
= 1.0 10^10 for Ka-band transmitters
X1 to X4 have the same values as T1 to T4 but
are dependent on the exciter band (Item 13)
RTLT is the round-trip light time
For Doppler data the residual (sometimes called the
pseudo-residual) is the observed Doppler minus the predicted
Doppler
A range observable is computed as follows:
Observable = R - C + Z - S
where:
R = range measurement
C = station delay calibration
Z = Z correction, which is the delay resulting from DSN
station optics that is not included in routine closed
loop calibrations (C)
S = spacecraft delay
Observable, fractional part
4
13
SignedMSB4
4
Item 5: The fractional part of the observable.
Multiply the value in this field by 10^-9 and
add the result to the result in Field 3. See DESCRIPTION
under Field 3 for details.
Items 6-14
5
17
UnsignedBitString
4
Items 6-14 of the ODF Orbit Data Group Data.
9
Format ID
1
1
3
UnsignedBitString
Item 6: The Format ID. Set to 2.
If this value is 1, the ODF was created on or before
1997-04-14 and will not be accurately described by this
set of object definitions. In that case, see:
JPL/DSN Document 820-13; Rev A
DSN System Requirements
Detail Interface Design
TRK-2-18
DSN Tracking System Interfaces
Orbit Data File Interface
Mark IVA
Effective Date: May 15, 1984
Receiving Station ID
2
4
10
UnsignedBitString
Item 7: The ID number of the primary
receiving antenna. Numbers can be found
in DSN document 810-047, DSN Antenna and
Facility Identifiers, DSN Standard Practice.
Transmitting Station ID
3
11
17
UnsignedBitString
Item 8: The ID number of the transmitting antenna.
Set to zero if no transmitter was involved (quasar VLBI,
one-way (Doppler, phase, or range), or angles data.
Numbers can be found in DSN document 810-047, DSN
Antenna and Facility Identifiers, DSN Standard Practice.
Network ID
4
18
19
UnsignedBitString
Item 9: Network ID Number for the transmitting
antenna: Set to:
0 for DSN
1 for other
2 for UPL (Uplink Tracking and
Command System)
Data Type ID
5
20
25
UnsignedBitString
Item 10: Data Type ID Number.
Allowed data type values include:
01 = Delta Differential One-way Doppler (D-DOD), Doppler mode, in Hz
02 = Delta Differential One-way Doppler (D-DOD), phase mode, in cycles
03 = Delta Differential One-way Doppler (D-DOD), Doppler mode, in Hz
04 = Delta Differential One-way Doppler (D-DOD), phase mode, in cycles
05 = Delta Differential One-way Ranging (D-DOR), in nanoseconds
06 = Delta Differential One-way Ranging (D-DOR), in nanoseconds
11 = One-way Doppler, in Hertz
12 = Two-way Doppler, in Hertz
13 = Three-way Doppler, in Hertz
37 = Sequential Range, in Range Units (RU)
41 = RE (Tone) Range, in nanoseconds
51 = Azimuth angle, in degrees
52 = Elevation angle, in degrees
53 = Hour angle, in degrees
54 = Declination angle, in degrees
55 = X angle (where +X is east), in degrees
56 = Y angle (where +X is east), in degrees
57 = X angle (where +X is south), in degrees
58 = Y angle (where +X is south), in degrees
Downlink Band ID
6
26
27
UnsignedBitString
Item 11: Downlink Band ID. Allowed
values include:
0 = Not applicable if angle data,
Ku-band otherwise
1 = S-band
2 = X-band
3 = Ka-band
Uplink Band ID
7
28
29
UnsignedBitString
Item 12: Uplink Band ID. Allowed
values include:
0 = Not applicable if angle data or 1-way data,
Ku-band otherwise
1 = S-band
2 = X-band
3 = Ka-band
Reference Frequency Band ID
8
30
31
UnsignedBitString
Item 13: Reference frequency band ID. Allowed
values include:
0 = Not applicable if angle data,
Ku-band otherwise
1 = S-band
2 = X-band
3 = Ka-band
Data Validity Indicator
9
32
32
UnsignedBitString
Item 14: The data validity flag. Values are:
0 = valid
1 = invalid
Items 15-19
6
21
UnsignedBitString
8
Items 15-19 of the ODF Orbit Data Group Data.
5
Item 15
1
1
7
UnsignedBitString
Item 15: If data type (Item 10) is:
01-06, the ID number of the second receiving antenna, per 810-047;
11-13, the receiver channel number (0-24);
37, the ranging component with the lowest frequency (1-24);
41, integer seconds of the observable;
51-58, reserved (set to 0).
Item 16
2
8
17
UnsignedBitString
Item 16: If data type (Item 10) is:
01-06, the Quasar ID (per DSN document 810-005 Module 107 or
the Spacecraft ID (per DSN document 820-013, OPS-6-21);
11-58, the Spacecraft ID (per DSN document 820-013, OPS-6-21).
Item 17
3
18
18
UnsignedBitString
Item 17: If data type (Item 10) is:
01-04, the Phase Point Indicator (set to 0);
05-06, the Modulus Indicator (0 = modded, 1 = unmodded);
11-13, a flag that indicates whether ramps (if available) should
be used to replace the receiver reference frequency
(0 = both transmitter and receiver are ramped,
1 = transmitter is ramped, receiver is not ramped);
37, reserved (set to 1)
41-58, reserved (set to 0)
Item 18
4
19
40
UnsignedBitString
Item 18: If data type (Item 10) is:
01-41, the Reference Frequency (High-Part), in 2^24 mHz,
where Reference Frequency (High-Part) is
trunc(1000*Variable/2^24) and
Variable is Reference Frequency in Hz;
51-58, reserved (set to 0).
Item 19
5
41
64
UnsignedBitString
Item 19: If data type (Item 10) is:
01-41, Reference Frequency (Low-Part), in mHz,
where Reference Frequency (Low-Part) is
trunc((1000*Variable) modulo 2^24) and
Variable is Reference Frequency in Hz;
51-58, reserved (set to 0).
Items 20-22
7
29
UnsignedBitString
8
Items 20-22 of the ODF Orbit Data Group Data.
3
Item 20
1
1
20
SignedBitString
Item 20: If data type (Item 10) is:
01-04, the value is called Composite 1 and is calculated as
(Phase Calibration Flag minus 1) times 100000, plus
Channel ID times 10000 where Phase Calibration Flag is
1 = no calibration,
2 = default calibration,
3 = quasar calibration only,
4 = spacecraft calibration only, or
5 = quasar and spacecraft calibration;
05-06, the value is called Composite 1 and is calculated as
(Channel Sampling Flag minus 1) times 100000, plus
Mode ID times 10000 plus Modulus High-Part in
10^-1 nanoseconds where
Channel Sampling Flag is
1 = multiplexed, or
2 = parallel,
Mode ID is
0 = one-way, or
1 = two-way
Modulus High-Part is trunc(Variable*10), and
Variable is Modulus in nanoseconds;
11-13, reserved (set to 0);
37, the uplink ranging coder in-phase time offset from
the sample time tag, in seconds;
41-58 reserved (set to 0);
Item 21
2
21
42
UnsignedBitString
Item 21: If data type (Item 10) is:
01-04, the Compression Time, in 0.01 seconds;
05-06, the Modulus (Low-Part), in 10^-7 seconds, where
Modulus (Low-Part) is trunc((10^7*Variable) modulo 10^6)
and Variable is Modulus in nanoseconds;
11-13, the Compression Time, in 0.01 seconds;
37, the value is called Composite 2 and is calculated as
the highest ranging component times 100000, plus the downlink
ranging coder in-phase time offset from the sample time tag,
in seconds;
41-58, reserved (set to 0).
Item 22
3
43
64
UnsignedBitString
Item 22: If data type (Item 10) is:
01-06, the second receiving antenna downlink delay, in nanoseconds;
11-41, the transmitting antenna uplink delay, in nanoseconds,
which is always zero for one-way;
51-58, reserved (set to 0).
If VLBI data:
Second Receiving Station Downlink Delay in nanoseconds.
If Doppler, phase, or range data:
Transmitting Station Uplink Delay in nanoseconds.
Otherwise, set to 0.
ODF Ramp Group Header (Station 63)
80388
1
Ramp Groups usually begin as
the fourth of several groups of records in an
Orbit Data File (ODF). They contain information on
tuning of receivers or transmitters. There is usually
one Ramp Group for each DSN station. The Ramp Group
Header is the first record in each Ramp Group. It is
one 36-byte record and is followed by one or more 36-
byte Ramp Group data records. Data records are time
ordered within each Ramp Group. The Ramp Group may be
omitted from an ODF. The row suffix bytes in the Ramp
Group Header are set to 0.
4
1
36
Primary Key
1
1
SignedMSB4
4
Item 1: The Primary Key indicates the type
of data records to follow. In the Ramp Group Header
this field is set to 2030.
Secondary Key
2
5
UnsignedMSB4
4
Item 2: Set to the Station (antenna) ID Number.
Numbers may be found in DSN document 810-047.
If not applicable, the value is set to zero.
Logical Record Length (in packets)
3
9
UnsignedMSB4
4
Item 3: The Logical Record Length gives the
number of 36-byte physical records making up each logical
record in a Ramp Group data record. For the Ramp Group
it is set to 1.
Group Start Packet Number
4
13
UnsignedMSB4
4
Item 4: The Group Start Packet Number
gives the number of the ODF packet containing the
Ramp Group Header; packet numbering starts with 0
for the File Label Group Header.
Items 5-9
5
1
0
17
20
Suffix Bytes
1
1
UnsignedMSB4
4
The bytes to fill the record; set to 0.
ODF Ramp Group Data (Station 63)
80424
97
Ramp Groups usually begin as
the fourth of several groups of records in an
Orbit Data File (ODF). They contain information on
tuning of receivers or transmitters. There is usually
one Ramp Group for each DSN station. The Ramp Group
Header is the first record in each Ramp Group. It is
one 36-byte record and is followed by one or more 36-
byte Ramp Group data records. Data records are time
ordered within each Ramp Group. The Ramp Group may be
omitted from an ODF.
9
0
36
Ramp Start Time, integer part
1
1
UnsignedMSB4
4
second
Item 1: The integer part of the ramp
start time, measured in seconds from the
Reference Time (usually 0 hours UTC on
1 January 1950).
Ramp Start Time, fractional part
2
5
UnsignedMSB4
4
nanosecond
Item 2: The fractional part of the ramp
start time - see field 1 (Item 1).
Ramp Rate, integer part
3
9
SignedMSB4
4
Hz/second
Item 3: The integer part of the ramp rate.
Ramp Rate, fractional part
4
13
SignedMSB4
4
nanohertz/second
Item 4: The fractional part of the ramp
rate, in units of 10^-9 of field 3i (Item 3).
Items 5-6
5
17
UnsignedBitString
4
Items 5-6 of the ODF.
2
Ramp Start Frequency, integer GHz
1
1
22
UnsignedBitString
GHz
Item 5: Ramp Start Frequency, integer GHz.
Transmitting Station ID
2
23
32
UnsignedBitString
Item 6:Transmitting Station ID number.
Numbers can be found in DSN document 810-047.
Ramp Start Frequency, integer part modulo 10^9
6
21
UnsignedMSB4
4
Hertz
Item 7: The integer part of the
Ramp Start Frequency, modulo 10^9.
Ramp Start Frequency, fractional part
7
25
UnsignedMSB4
4
Item 8: The fractional part of the
Ramp Start Frequency, in units of 10^-9 of field 6 (Item 7).
Ramp End Time, integer part
8
29
UnsignedMSB4
4
second
Item 9: The integer part of the ramp
end time, measured from the Reference Time
(usually 0 hours UTC on 1 January 1950).
Ramp End Time, fractional part
9
33
UnsignedMSB4
4
nanosecond
Item 10: The fractional part of the ramp
end time (see field 8, Item 9).
ODF Ramp Group Header (Station 14)
83916
1
Ramp Groups usually begin as
the fourth of several groups of records in an
Orbit Data File (ODF). They contain information on
tuning of receivers or transmitters. There is usually
one Ramp Group for each DSN station. The Ramp Group
Header is the first record in each Ramp Group. It is
one 36-byte record and is followed by one or more 36-
byte Ramp Group data records. Data records are time
ordered within each Ramp Group. The Ramp Group may be
omitted from an ODF. The row suffix bytes in the Ramp
Group Header are set to 0.
4
1
36
Primary Key
1
1
SignedMSB4
4
Item 1: The Primary Key indicates the type
of data records to follow. In the Ramp Group Header
this field is set to 2030.
Secondary Key
2
5
UnsignedMSB4
4
Item 2: Set to the Station (antenna) ID Number.
Numbers may be found in DSN document 810-047.
If not applicable, the value is set to zero.
Logical Record Length (in packets)
3
9
UnsignedMSB4
4
Item 3: The Logical Record Length gives the
number of 36-byte physical records making up each logical
record in a Ramp Group data record. For the Ramp Group
it is set to 1.
Group Start Packet Number
4
13
UnsignedMSB4
4
Item 4: The Group Start Packet Number
gives the number of the ODF packet containing the
Ramp Group Header; packet numbering starts with 0
for the File Label Group Header.
Items 5-9
5
1
0
17
20
Suffix Bytes
1
1
UnsignedMSB4
4
The bytes to fill the record; set to 0.
ODF Ramp Group Data (Station 14)
83952
48
Ramp Groups usually begin as
the fourth of several groups of records in an
Orbit Data File (ODF). They contain information on
tuning of receivers or transmitters. There is usually
one Ramp Group for each DSN station. The Ramp Group
Header is the first record in each Ramp Group. It is
one 36-byte record and is followed by one or more 36-
byte Ramp Group data records. Data records are time
ordered within each Ramp Group. The Ramp Group may be
omitted from an ODF.
9
0
36
Ramp Start Time, integer part
1
1
UnsignedMSB4
4
second
Item 1: The integer part of the ramp
start time, measured in seconds from the
Reference Time (usually 0 hours UTC on
1 January 1950).
Ramp Start Time, fractional part
2
5
UnsignedMSB4
4
nanosecond
Item 2: The fractional part of the ramp
start time - see field 1 (Item 1).
Ramp Rate, integer part
3
9
SignedMSB4
4
Hz/second
Item 3: The integer part of the ramp rate.
Ramp Rate, fractional part
4
13
SignedMSB4
4
nanohertz/second
Item 4: The fractional part of the ramp
rate, in units of 10^-9 of field 3i (Item 3).
Items 5-6
5
17
UnsignedBitString
4
Items 5-6 of the ODF.
2
Ramp Start Frequency, integer GHz
1
1
22
UnsignedBitString
GHz
Item 5: Ramp Start Frequency, integer GHz.
Transmitting Station ID
2
23
32
UnsignedBitString
Item 6:Transmitting Station ID number.
Numbers can be found in DSN document 810-047.
Ramp Start Frequency, integer part modulo 10^9
6
21
UnsignedMSB4
4
Hertz
Item 7: The integer part of the
Ramp Start Frequency, modulo 10^9.
Ramp Start Frequency, fractional part
7
25
UnsignedMSB4
4
Item 8: The fractional part of the
Ramp Start Frequency, in units of 10^-9 of field 6 (Item 7).
Ramp End Time, integer part
8
29
UnsignedMSB4
4
second
Item 9: The integer part of the ramp
end time, measured from the Reference Time
(usually 0 hours UTC on 1 January 1950).
Ramp End Time, fractional part
9
33
UnsignedMSB4
4
nanosecond
Item 10: The fractional part of the ramp
end time (see field 8, Item 9).
ODF Ramp Group Header (Station 43)
85680
1
Ramp Groups usually begin as
the fourth of several groups of records in an
Orbit Data File (ODF). They contain information on
tuning of receivers or transmitters. There is usually
one Ramp Group for each DSN station. The Ramp Group
Header is the first record in each Ramp Group. It is
one 36-byte record and is followed by one or more 36-
byte Ramp Group data records. Data records are time
ordered within each Ramp Group. The Ramp Group may be
omitted from an ODF. The row suffix bytes in the Ramp
Group Header are set to 0.
4
1
36
Primary Key
1
1
SignedMSB4
4
Item 1: The Primary Key indicates the type
of data records to follow. In the Ramp Group Header
this field is set to 2030.
Secondary Key
2
5
UnsignedMSB4
4
Item 2: Set to the Station (antenna) ID Number.
Numbers may be found in DSN document 810-047.
If not applicable, the value is set to zero.
Logical Record Length (in packets)
3
9
UnsignedMSB4
4
Item 3: The Logical Record Length gives the
number of 36-byte physical records making up each logical
record in a Ramp Group data record. For the Ramp Group
it is set to 1.
Group Start Packet Number
4
13
UnsignedMSB4
4
Item 4: The Group Start Packet Number
gives the number of the ODF packet containing the
Ramp Group Header; packet numbering starts with 0
for the File Label Group Header.
Items 5-9
5
1
0
17
20
Suffix Bytes
1
1
UnsignedMSB4
4
The bytes to fill the record; set to 0.
ODF Ramp Group Data (Station 43)
85716
24
Ramp Groups usually begin as
the fourth of several groups of records in an
Orbit Data File (ODF). They contain information on
tuning of receivers or transmitters. There is usually
one Ramp Group for each DSN station. The Ramp Group
Header is the first record in each Ramp Group. It is
one 36-byte record and is followed by one or more 36-
byte Ramp Group data records. Data records are time
ordered within each Ramp Group. The Ramp Group may be
omitted from an ODF.
9
0
36
Ramp Start Time, integer part
1
1
UnsignedMSB4
4
second
Item 1: The integer part of the ramp
start time, measured in seconds from the
Reference Time (usually 0 hours UTC on
1 January 1950).
Ramp Start Time, fractional part
2
5
UnsignedMSB4
4
nanosecond
Item 2: The fractional part of the ramp
start time - see field 1 (Item 1).
Ramp Rate, integer part
3
9
SignedMSB4
4
Hz/second
Item 3: The integer part of the ramp rate.
Ramp Rate, fractional part
4
13
SignedMSB4
4
nanohertz/second
Item 4: The fractional part of the ramp
rate, in units of 10^-9 of field 3i (Item 3).
Items 5-6
5
17
UnsignedBitString
4
Items 5-6 of the ODF.
2
Ramp Start Frequency, integer GHz
1
1
22
UnsignedBitString
GHz
Item 5: Ramp Start Frequency, integer GHz.
Transmitting Station ID
2
23
32
UnsignedBitString
Item 6:Transmitting Station ID number.
Numbers can be found in DSN document 810-047.
Ramp Start Frequency, integer part modulo 10^9
6
21
UnsignedMSB4
4
Hertz
Item 7: The integer part of the
Ramp Start Frequency, modulo 10^9.
Ramp Start Frequency, fractional part
7
25
UnsignedMSB4
4
Item 8: The fractional part of the
Ramp Start Frequency, in units of 10^-9 of field 6 (Item 7).
Ramp End Time, integer part
8
29
UnsignedMSB4
4
second
Item 9: The integer part of the ramp
end time, measured from the Reference Time
(usually 0 hours UTC on 1 January 1950).
Ramp End Time, fractional part
9
33
UnsignedMSB4
4
nanosecond
Item 10: The fractional part of the ramp
end time (see field 8, Item 9).
ODF End-of-File Group
86580
1
The End of File Group
is usually the eighth and last of several groups of
records in an Orbit Data File (ODF). It is a single
record of 36-bytes and denotes the logical end of the
ODF. Row suffix bytes are set to 0.
4
1
36
Primary Key
1
1
SignedMSB4
4
Item 1: The Primary Key indicates the type of data records to
follow. In the End of File Group Header this field is set to -1.
Secondary Key
2
5
UnsignedMSB4
4
Item 2: The Secondary Key is not used in the ODF. It is set to 0.
Logical Record Length (in packets)
3
9
UnsignedMSB4
4
Item 3: The Logical Record Length is set
to 0 in the End of File Group, indicating that no
logical records follow.
Group Start Packet Number
4
13
UnsignedMSB4
4
Item 4: The Group Start Packet Number
gives the number of the ODF packet containing the
End of File Group; packet numbering starts with 0
for the File Label Group Header.
Items 5-9
5
1
0
17
20
Suffix Bytes
1
1
UnsignedMSB4
4
The bytes to fill the record; set to 0.