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;
2018-06-18, D. Kazden (PPI), Updated STOP_TIME and DATA_SET_RELEASE_DATE;
2018-07-30, D. Kazden (PPI), removed ARCHIVE_STATUS keyword;"
RECORD_TYPE = STREAM
OBJECT = DATA_SET
DATA_SET_ID = "CO-V/E/J/S/SS-RPWS-2-REFDR-WFRFULL-V1.0"
OBJECT = DATA_SET_INFORMATION
DATA_SET_NAME = "
CASSINI V/E/J/S/SS RPWS EDITED WAVEFORM 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 = 2017-09-15T00:00:00.000
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 waveform (WFR) data set includes all waveform data for
the entire Cassini mission."
ABSTRACT_DESC = "
The Cassini Radio and Plasma Wave Science (RPWS) edited full
resolution data set includes all waveform data for the entire
Cassini mission. This data set includes uncalibrated values for
each waveform 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 Waveform
Receiver (WFR). 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 WFR modes (i.e. 2.5-kHz and 26
Hz modes) are segregated into separate files. This data set
includes all waveform 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 waveform data provide the highest resolution data
from the RPWS instrument in the form of a set of waveform series
for these two bandwidths and can be used, when data from two
electric and three magnetic sensors are available, to perform
wave-normal analyses on various plasma wave phenomena. 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 or to do the wave-normal analysis.
Usually, this data set includes time series measurements from more
than one (up to five) sensors at a time and the samples are made
simultaneously for all five sensors."
CITATION_DESC = "Kurth, W.S., W.T. Robison, and L.J.
Granroth, CASSINI V/E/J/S/SS RPWS EDITED WAVEFORM FULL RES V1.0,
CO-V/E/J/S/SS-RPWS-2-REFDR-WFRFULL-V1.0, NASA Planetary Data
System, 2004."
DATA_SET_DESC = "
Data Set Overview
=================
The Cassini Radio and Plasma Wave Science (RPWS) edited full
resolution data set includes all waveform data for the entire
Cassini mission. This data set includes uncalibrated values for
each waveform 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 are acquired from the RPWS Waveform Receiver
(WFR). 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 WFR modes (i.e. 2.5-kHz and 26 Hz modes) are
segregated into separate files. This data set includes all waveform
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 waveform data
provide the highest resolution data from the RPWS instrument in the
form of a set of waveform series for these two bandwidths and can be
used, when data from two electric and three magnetic sensors are
available, to perform wave-normal analyses on various plasma wave
phenomena. 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 or to do the
wave-normal analysis. Usually, this data set includes time series
measurements from more than one (up to five) sensors at a time and
the samples are made simultaneously for all five sensors.
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 the primary purpose of the WFR is to support wave-normal
analyses, the typical configuration of this receiver uses the
5-sensor combination mentioned above. The waveforms can be acquired
in one of two modes:
1. 2.5-kHz mode: 0.003 - 2.5 kHz, 140 microsecond sampling rate
2. 26-Hz mode: 1 - 26 Hz, 10 msec sampling rate
For each mode, one, two, three, or five individual sensors can be
selected. The samples are made simultaneously on each of the
sensors so as to preserve information on the phase relationships
between signals on the various sensors.
Typically, data are acquired in time series with length of a
multiple of 512 12-bit samples, usually with this length set to 2048
samples. For the 2.5-kHz mode, this results in time series of
duration about 287 msec and for the 26-Hz mode, the duration of the
waveform series is typically about 20 s. A new waveform series can
be acquired as often as once per approximately 20 seconds but
typically once every several minutes. Hence, the duty cycle for
this mode can be very small (e.g. 287 msec out of 300 sec or about
0.1 percent for the 2.5 kHz mode or about 7 percent for the 26-Hz
mode) with typical sample lengths. In some instrument modes the WFR
is exercised at a much higher duty cycle, at rates of once or twice
per minute, improving the duty cycle considerably.
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 onboard compression
schemes. These data may be calibrated using supplied calibration
factors and algorithms as well as sample code provided.
Data
====
The RPWS full resolution waveform data set is organized by receiver
mode and time series sample length in order to use 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 sample 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. Wave normal analysis typically
requires that the wave data and vector magnetic field from the
MAGNETOMETER instrument be used in a common coordinate system.
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 are provided which convert from data
number to either electric or magnetic field strength (units of
volt/meter or nanotesla). 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 waveform data for the Cassini RPWS
instrument for the interval described in the product label files.
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 waveform 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 2002, 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, waveform data are not acquired during
the interplanetary cruise phase. However, they are acquired more
regularly at low duty cycles during tour and near some of the
planetary flybys en route. 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 waveform 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.
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
|