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 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.