PDS_VERSION_ID                    = PDS3
LABEL_REVISION_NOTE               = "
  2004-06-21, ALAIN HERIQUE(SBN), INITIAL RELEASE;
  "
RECORD_TYPE                       = STREAM

OBJECT                            = INSTRUMENT
  INSTRUMENT_HOST_ID              = "RL"    /* also RO */
  INSTRUMENT_ID                   = "CONSERT"

  OBJECT                          = INSTRUMENT_INFORMATION
    INSTRUMENT_NAME               = "COMET NUCLEUS SOUNDING
                                     EXPERIMENT BY RADIOWAVE
                                     TRANSMISSION"
    INSTRUMENT_TYPE               = "RADAR"
    INSTRUMENT_DESC               = "

INSTRUMENT OVERVIEW
===================

THE COMPLETE CONSERT EXPERIMENT IS COMPOSED OF:

- ONE ORBITER PART (ELECTRONICS, ANTENNA, HARNESS)
- ONE LANDER  PART (ELECTRONICS, ANTENNAS,HARNESS)



SCIENTIFIC OBJECTIVES
=====================

Our experiment concerns the rough tomography of the comet nucleus
performed by the CONSERT instrument. It works as a time domain
transponder between one module which will land on the comet surface
(Lander) and another which will fly around the comet (Orbiter).
Basically, a 90 MHz sinusoidal waveform is phase modulated by a
pseudorandom code or PSK (phase shift keying) coding. Such frequency,
in the radio range, is expected to minimize the losses during the
propagation inside the comet material and the generated pulse code
maximizes the signal to noise ratio.
In these experimental conditions great attempt is made on the good
measurement of the mean dielectric properties and on the detection of
large size embedded structures or small irregularities withi the
comet nucleus.

CALIBRATION
===========

Due to the design of the instrument, there is no calibration data.
The science data is the propagation channel of the comet nucleus as
a function of time:
- The propagation time is the main data to be inverse and its
  accuracy is waranty by the consert clock absolute accuracy and
  stability.
- The signal amplitude can also provide information about the
  nucleus structure but there is no internal calibration channel
  to increase the link budget accuracy.

OPERATIONAL CONSIDERATIONS
==========================

The Lander makes a coherent addition and a detection of the
correlation principal peak. a clean coded signal is finally emitted
with the found delay. The orbiter accumulates the signal and sends it
to the Earth (via the satellite interface).

OPERATIONAL MODES
=================

Each scientific measurement sequence (called scanning sequence)
involves the Orbiter part and the Lander. The duration of this scan
sequence is related to the duration of the orbit of the Rosetta
spacecraft relatively to the Lander on the rotating comet nucleus.
This duration is typically of the order of one revolution around the
nucleus. During this scan sequence, about 3000 individual
measurements, called soundings are taken. the individual duration of
this sounding is less than one second.

This duration of scanning sequence  should
correspond to the time when the Lander and the Orbiter are separated
by the comet. During the direct line of sight periods, the
synchronization occurs. This means that the duration of the data
recording will not correspond to the total time of one revolution.
the number of samples is given by the following formula:
2 * pi *radius of comet/ (lambda/2)
where lambda is wavelength.
During the scanning sequence for a circular comet with a 750 m
radius, about 3000 individual measurements, called soundings are
taken.

The general structure of the consert operational scenario does not
depend on the comet type that will be explored during the Rosetta
mission. but a certain amount of the parameters dependent on the
shape and size of the comet nucleus and of the orbit of the
spacecraft and nucleus rotation.


MEASURED PARAMETERS
===================

- TUNING ON O: CONSERT/ORIBITER switch-on time (in UT)
- TUNING ON L: CONSERT/LANDER   switch-on time (in UT)
- TUNESTART O: start time for CONSERT/ORBITER clock tuning mode
               (in UT)
- TUNESTART L: start time for CONSERT/LANDER  clock tuning mode
               (in UT)
- SOUND START: CONSERT/ORBITER and CONSERT/LANDER sounding start time
               (in UT)
- NB SOUND   : total number of soundings performed by CONSERT/ORBITER
               and CONSERT/LANDER
- DELTA SOUND: period between each sounding
- BOARD TEMPERATURE
"
  END_OBJECT                      = INSTRUMENT_INFORMATION

  OBJECT                          = INSTRUMENT_REFERENCE_INFO
    REFERENCE_KEY_ID              = "KOFMANETAL2007"
  END_OBJECT                      = INSTRUMENT_REFERENCE_INFO

END_OBJECT                        = INSTRUMENT

END