PDS_VERSION_ID = PDS3
LABEL_REVISION_NOTE = "
2003-01-12, William Kurth (U. IOWA), initial;
2003-06-26, William Kurth (U. IOWA), general revision;
2004-02-10, William Kurth (U. IOWA), fixed liens;
2005-06-25, Larry Granroth (U. IOWA), minor tweaks;
2006-03-05, Larry Granroth (U. IOWA), added to limitations section;
2009-06-17, Chris Piker (U. IOWA), removed illegal keyword;
2012-06-20, Chris Piker (U. IOWA), add SCET miscalculation section;
2018-06-13, D. Kazden (PPI), Updated STOP_TIME and DATA_SET_RELEASE_DATE;
2018-07-30, D. Kazden (PPI), Removed ARCHIVE_STATUS keyword;
2020-02-04, D. Kazden (PPI), Updated CITATION_DESC;"
RECORD_TYPE = STREAM
OBJECT = DATA_SET
DATA_SET_ID = "CO-V/E/J/S/SS-RPWS-2-REFDR-WBRFULL-V1.0"
OBJECT = DATA_SET_INFORMATION
DATA_SET_NAME = "
CASSINI V/E/J/S/SS RPWS EDITED WIDEBAND FULL RES V1.0"
DATA_SET_COLLECTION_MEMBER_FLG = "N"
DATA_OBJECT_TYPE = TIME_SERIES
START_TIME = 1997-10-25T00:00:00.000
STOP_TIME = 2017-09-15T06:00:00.000
DATA_SET_RELEASE_DATE = 2018-07-01
PRODUCER_FULL_NAME = "DR. WILLIAM S. KURTH"
DETAILED_CATALOG_FLAG = "N"
DATA_SET_TERSE_DESC = "
The Cassini Radio and Plasma Wave Science (RPWS) edited full
resolution wideband (WBR) data set includes all wideband waveform
data for the entire Cassini mission."
ABSTRACT_DESC = "
The Cassini Radio and Plasma Wave Science (RPWS) edited full
resolution data set includes all wideband waveform data for the
entire Cassini mission. This data set includes uncalibrated
values for each wideband channel for each sensor for all times
during the mission including the second Venus flyby, the Earth
flyby, the Jupiter flyby, interplanetary cruise, and the entire
Saturn tour. Data for this data set are acquired from the RPWS
Wideband Receiver (WBR). Data are presented in a set of time
series organized so as to have fixed-length records for ease in
data handling. Data from the different WBR modes (i.e. 10-kHz,
80-kHz, and frequency-translated 80-kHz data) are segregated into
separate files. This data set includes all wideband data acquired
by the RPWS. A browse data set is included with these data which
provides for a graphical search of the data using a series of
thumbnail and full-sized spectrograms which lead the user to the
particular data file(s) of interest. The wideband data provide the
highest resolution data from the RPWS instrument in the form of a
set of waveform series. These data can be used in their original
time domain in order to look for solitary features such as dust
impacts or electrostatic solitary waves. Or, they can be
transformed into the frequency domain in order to examine the
detailed time and spectral evolution of plasma waves or radio
emissions."
CITATION_DESC = "Kurth, W.S., W.T. Robison, and L.J.
Granroth, CASSINI V/E/J/S/SS RPWS EDITED WIDEBAND FULL RES V1.0,
CO-V/E/J/S/SS-RPWS-2-REFDR-WBRFULL-V1.0, NASA Planetary Data
System, 2018."
DATA_SET_DESC = "
Data Set Overview
=================
The Cassini Radio and Plasma Wave Science (RPWS) edited full
resolution data set includes all wideband waveform data for the
entire Cassini mission. This data set includes uncalibrated values
for each wideband channel for each sensor for all times during the
mission including the second Venus flyby, the Earth flyby, the
Jupiter flyby, interplanetary cruise, and the entire Saturn tour.
Data for this data set are acquired from the RPWS Wideband Receiver
(WBR). Data are presented in a set of time series organized so as
to have fixed-length records for ease in data handling. Data from
the different WBR modes (i.e. 10-kHz, 80-kHz, and
frequency-translated 80-kHz data) are segregated into separate
files. This data set includes all wideband data acquired by the
RPWS. A browse data set is included with these data which provides
for a graphical search of the data using a series of thumbnail and
full-sized spectrograms which lead the user to the particular data
file(s) of interest. The wideband data provide the highest
resolution data from the RPWS instrument in the form of a set of
waveform series. These data can be used in their original time
domain in order to look for solitary features such as dust impacts
or electrostatic solitary waves. Or, they can be transformed into
the frequency domain in order to examine the detailed time an
spectral evolution of plasma waves or radio emissions.
Parameters
==========
This data set comprises time series of data numbers related to the
potential difference at the preamp input to the RPWS. The data
numbers can be calibrated with the use of supplied algorithms and
calibration factors to generate a time series of electric or
magnetic field waveforms in units of Volts/meter or nanoTesla.
Because of the enhanced sensitivity of the electric antennas,
most data in this data set are acquired using the Ex dipole
antenna. The waveforms can be acquired in one of three modes:
1. 10-kHz baseband mode: 0.06 - 10.5 kHz, 36 microsecond sampling
rate
2. 75-kHz baseband mode: 0.8 - 75 kHz, 4.5 microsecond sampling
rate
3. 75-kHz frequency translation mode; 25-kHz bandwidth
down-converted to the frequency range of 50 to 75 kHz, 4.5
microsecond sampling rate.
In the third mode, the frequency range analyzed is selectable from a
range of 125 kHz to 16 MHz.
Typically, data are acquired in time series with length of a
multiple of 512 8-bit samples, usually with this length set to 2048
samples. For the 10-kHz mode, this results in time series of
duration about 74 msec and for the 75-kHz mode, the duration of the
waveform series is typically about 9 msec. A new waveform series
can be acquired as often as once per 125 msec. Hence, the duty
cycle for this mode can be very small (e.g. 9 msec out of 125 msec
or about 7 percent for the 75 kHz mode or closer to 50 percent for
the 10-kHz mode) with typical sample lengths.
Processing
==========
Data in this data set were processed by the use of a number of
software programs which assemble segmented mini-packets in the raw
telemetry packets into complete sets and de-compress the data that
were compressed by one of several possible compression algorithms.
These data may be calibrated using supplied calibration factors and
algorithms as well as sample code provided.
Data
====
The RPWS full resolution wideband data set is organized by receiver
mode and time series sample length in order to generate files with
fixed record lengths. Each time series is a record in a file with
header information on time, sensor, and receiver gain (required for
calibration). Separate files will be maintained for each instrument
mode and time series length.
Ancillary Data
==============
Ancillary data included with this data set collection include a
series of files that describe the modes of the RPWS as a function of
time and provide a time-ordered listing of Instrument Expanded Block
(IEB) trigger commands (the mode by which the RPWS is reconfigured).
Also a detailed description of each of the modes (or IEBs) is
provided.
Other data which are ancillary to this data set but which are
archived separately from this collection are the Navigation and
Ancillary Information Facility's SPICE kernels describing the
position and attitude of Cassini and various solar system bodies as
a function of time.
Coordinate System
=================
The data in this data set are measurements of wave electric and
magnetic fields measured by the RPWS electric and magnetic sensors.
These fields are presented as detected by the sensors and are not
rotated into any other coordinate system. If desired the SPICE
kernels can be used with the SPICE toolkit to convert from the
spacecraft frame to virtually any frame which may be of use in
analyzing these data. However, for many purposes, the wave
amplitudes are extremely useful and may be entirely adequate with no
coordinate transformations at all.
Software
========
Sample code is provided with these data which demonstrates how to
read these files in order to build a set of waveform time series.
Algorithms and sample code is provided which convert from data
number to either electric or magnetic field strength (units of
volt/meter or nanoTesla). Sample code and algorithms are also
included to perform these conversions. The sample code and
algorithms are found in the EXTRAS/SOFTWARE directory. A
description of how to access and calibrate these data is included in
WBRWFR.TXT in the DOCUMENT directory. Also see the RPWSCAL document
in the same directory.
Media/Format
============
These data are supplied to the Planetary Data System on DVD-R media
using formats and standards of the PDS for such media."
CONFIDENCE_LEVEL_NOTE = "
Confidence Level Overview
=========================
This data set contains all wideband data for the Cassini RPWS
instrument for the interval described above. Every effort has been
made to ensure that all data returned to JPL from the spacecraft is
included and that the calibration information is accurate.
Review
======
The RPWS full resolution wideband data will be reviewed internally
by the Cassini RPWS team prior to release to the PDS. The data set
will also be peer reviewed by the PDS.
Data Coverage and Quality
=========================
All data in the stated interval are included, to the best of our
knowledge and attempts to determine completeness. In general, these
data were acquired during early tour for the following intervals:
1. Antenna deployment 1997-10-25T00:00 - 1997-10-26T05:30
2. Instrument Checkout 1998-12-30T09:10 - 1999-01-19T05:40
3. Venus 2 flyby 1999-06-24T09:08 - 1999-06-24T21:20
4. Earth flyby 1999-08-13T17:39 - 1999-09-14T22:20
*Actual interval for science data is much shorter than this.
Beginning in February of 2000 the instrument was operated
more-or-less continuously; two gaps of the order of six weeks were
incurred for the purposes of loading new attitude control and
command and data system flight software, gaps of a few days each
were incurred approximately twice per year because of Huygens Probe
testing, and gaps of several days in duration occurred during solar
conjunction periods prior to 2002. Remaining gaps are due to
spacecraft anomaly resolution or simply to downlink gaps, some of
which were imposed by limitations on DSN station availability.
During the time interval after February 2000, the wideband data were
acquired during such times when the onboard solid state recorder and
the downlink capability could support the high data volumes required
for these data. Typically, the data are acquired for brief
intervals every several days or weeks during the interplanetary
cruise phase and more regularly but still just briefly every few
hours or so during tour. A user would find events of interest in
the more continuous low rate data and consult the ancillary sequence
information provided to determine the existence of wideband data in
an appropriate mode for that event. Further, a graphical browse
data set is supplied with the archive to allow the user to look at
frequency-time spectrograms directly in order to find events or
phenomena of interest. This browse system will point the user to
the data files containing the data of interest.
Limitations
===========
Beginning approximately with Saturn orbit insertion in early July
2005, the RPWS has shown increasing sensitivity in its electric
field measurements below 2 kHz to interference from the spacecraft
reaction wheels. The wheels are a source of electromagnetic
interference in the magnetic channels at frequencies directly
related to the rotation rate of the wheels due to a residual
magnetic moment in the wheels. This level was predicted before
launch and has been basically constant through flight. However, at
the earliest opportunity to observe the interference of the wheels
on the electric field measurements, there was essentially no
detectable level of interference. However, after orbit insertion,
it became clear with increasing time that the wheels were becoming
an increasing source of interference in the electric field
measurements at about 2 kHz and below. As of late 2005, the
amplitude of this interference is of the order of 30 or 40 dB above
the instrument noise level. The relation of the frequency of the
electric interference to the rotation rate of the wheels is less
direct than for the magnetic interference. There is a general
correspondence, but not in detail. It appears that there are some
frequencies more susceptible to the interference than others and
when the wheel speed approaches these 'resonances', the interference
becomes more visible. A working model for this interference
proposes that radiation effects on some part(s) of the spacecraft,
perhaps the thermal blankets, reduce the conductivity. Small
vibrations of this part(s), then, with some residual differential
charging then result in the electric field interference. This model
is not confirmed and the true explanation of the interference is
unknown, but the effects significantly complicate the interpretation
of the electric field spectrum below 2 kHz.
Some records in this data set do not contain full 8-bit resolution.
These records are emitted when the on-board dust hit detection
algorithm emits a sample dust hit waveform. The upper 4-bits of each
value are significant and the remaining lower bits have been set to 0.
Files containing dust hit algorithm records are indicated by the file
name pattern Tyyyyyyy_hh_10KHZD_WBRFR.DAT, but are not otherwise
marked in any special manner in the corresponding product labels or
in any of the data product header or record fields.
SCET Miscalculation
===================
Version 1 of CORPWS data
2008-12-28 through 2011-06-30
were processed using invalid SPICE spacecraft clock kernels.
Specifically the SCLKs which spice was asked to convert to SCETs
were outside the valid correlation region. The error was subtle at
first but continued to grow as SCLKs further from the correlated
region were converted to SCETs. The net result was that incorrect
SCET values were placed into the product files and product label
files for these dates. The issue has been corrected and no longer
affects any CORPWS datasets available from the PDS. The following
table lists the maximum SCET errors by date.
Start Date Stop Date Version Release Date Max SCET error
----------- ---------- -------- ------------- ---------------
2008-12-28 2009-01-12 1 2009-09-25 1.2 seconds
2009-01-13 2009-01-29 1 2009-12-17 1.3 seconds
2009-01-30 2009-02-12 1 2009-12-17 1.3 seconds
2009-02-13 2009-03-01 1 2009-12-17 1.4 seconds
2009-03-02 2009-03-29 1 2009-12-17 1.5 seconds
2009-03-30 2009-04-19 1 2009-12-17 1.5 seconds
2009-04-20 2009-05-16 1 2009-12-18 1.6 seconds
2009-05-17 2009-06-12 1 2009-12-18 1.7 seconds
2009-06-13 2009-06-26 1 2009-12-18 1.7 seconds
2009-06-27 2009-07-09 1 2009-12-18 1.7 seconds
2009-07-10 2009-07-25 1 2010-06-28 1.8 seconds
2009-07-26 2009-08-17 1 2010-06-28 1.9 seconds
2009-08-18 2009-09-09 1 2010-06-29 1.9 seconds
2009-09-10 2009-10-01 1 2010-06-30 1.9 seconds
2009-10-02 2009-10-21 1 2010-09-21 1.8 seconds
2009-10-22 2009-11-14 1 2010-09-21 1.9 seconds
2009-11-15 2009-12-10 1 2010-09-21 2.0 seconds
2009-12-11 2009-12-23 1 2010-09-21 2.0 seconds
2009-12-24 2010-01-13 1 2010-09-21 2.1 seconds
2010-01-14 2010-01-23 1 2010-09-21 2.2 seconds
2010-01-24 2010-02-02 1 2010-12-22 2.2 seconds
2010-02-03 2010-02-17 1 2010-12-22 2.2 seconds
2010-02-18 2010-02-27 1 2010-12-22 2.2 seconds
2010-02-28 2010-03-11 1 2010-12-22 2.3 seconds
2010-03-12 2010-03-22 1 2010-12-22 2.3 seconds
2010-03-23 2010-03-31 1 2010-12-22 2.4 seconds
2010-04-01 2010-04-16 1 2010-12-22 2.5 seconds
2010-04-17 2010-04-29 1 2010-12-22 2.6 seconds
2010-04-30 2010-05-10 1 2010-12-22 2.6 seconds
2010-05-11 2010-05-25 1 2010-12-22 2.7 seconds
2010-05-26 2010-06-08 1 2010-12-22 2.8 seconds
2010-06-09 2010-06-25 1 2010-12-23 2.9 seconds
2010-06-26 2010-08-07 1 2011-03-23 3.3 seconds
2010-08-08 2010-09-08 1 2011-03-23 3.6 seconds
2010-09-09 2010-10-15 1 2011-03-23 3.9 seconds
2010-10-16 2010-11-29 1 2011-09-29 4.1 seconds
2010-11-30 2011-01-03 1 2011-09-30 2.4 seconds
2011-01-04 2011-02-13 1 2011-12-21 2.7 seconds
2011-02-14 2011-03-24 1 2011-12-21 5.3 seconds
2011-03-25 2011-04-24 1 2011-12-21 7.3 seconds
2011-04-25 2011-05-09 1 2011-12-21 8.3 seconds
2011-05-10 2011-05-26 1 2011-12-22 9.4 seconds
2011-05-27 2011-06-12 1 2011-12-22 10.5 seconds
2011-06-13 2011-06-30 1 2011-12-22 11.7 seconds
Only data from 2008-12-28 through 2011-06-30 with
VERSION_VERSION_ID = 1
are affected. If VERSION_VERSION_ID is greater than 1, or the date
is before 2008-12-28, or the the date is after 2011-06-30, then the
data in question is unaffected by this issue.
"
END_OBJECT = DATA_SET_INFORMATION
OBJECT = DATA_SET_TARGET
TARGET_NAME = VENUS
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = EARTH
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = JUPITER
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = SATURN
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = SOLAR_SYSTEM
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = TITAN
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = ENCELADUS
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = MIMAS
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = DIONE
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = TETHYS
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = PHOEBE
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = IAPETUS
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = HYPERION
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_TARGET
TARGET_NAME = RHEA
END_OBJECT = DATA_SET_TARGET
OBJECT = DATA_SET_HOST
INSTRUMENT_HOST_ID = CO
INSTRUMENT_ID = RPWS
END_OBJECT = DATA_SET_HOST
OBJECT = DATA_SET_MISSION
MISSION_NAME = "CASSINI-HUYGENS"
END_OBJECT = DATA_SET_MISSION
OBJECT = DATA_SET_REFERENCE_INFORMATION
REFERENCE_KEY_ID = "GURNETTETAL2004"
END_OBJECT = DATA_SET_REFERENCE_INFORMATION
END_OBJECT = DATA_SET
END
|