PDS_VERSION_ID                   = PDS3                                       
RECORD_TYPE                      = FIXED_LENGTH                               
RECORD_BYTES                     = 80                                         
RELEASE_ID                       = 0001                                       
REVISION_ID                      = 0000                                       
OBJECT                           = TEXT                                       
  PUBLICATION_DATE               = 2010-05-18                                 
  NOTE                           = "Description of the GEOMETRY directory     
                                   contents for the Venus Express SPICAV      
                                   level 0B IR archive volume"                
END_OBJECT                       = TEXT                                       
END                                                                           
                                                                              
                   GEOMETRY Directory Contents                                
                                                                              
                                                                              
******************************************************************************
                                                                              
The time sampling period for the level 0B - IR DATA file is :                 
                                                                              
    time_spectrum = time_session * NUMBER_SESSIONS                            
                                                                              
with :                                                                        
    NUMBER_SESSIONS : Number of sessions by spectrum (one IR spectrum is      
                       divided into several communication sessions)           
    time_session = ceil(MODE_TIME(COMMAND_MODE_TIME)*332/1000) = 0A level time
                   sampling period                                            
    MODE_TIME=[1.4,2.8,5.6,11.2]                                              
    COMMAND_MODE_TIME :AOTF chopping period : 0- 1.4 ms, 1- 2.8 ms,           
                             2- 5.6 ms, 3- 11.2 ms                            
                                                                              
    Values of NUMBER_SESSIONS and COMMAND_MODE_TIME are obtained by reading   
    the IR data (see IR label file)                                           
                                                                              
    WARNING:                                                                  
    --------                                                                  
    For the present GEOMETRY files associated to the level 0B - IR data files,
    the sampling used is the 0A level time sampling period. (= time_session)  
                                                                              
                                                                              
    REMINDER:                                                                 
    ---------                                                                 
    In level 0A IR data file, a record corresponds to one communication       
    session (one part of a  spectrum) from the two detectors.                 
    In level 0B IR data file contains all reconstructed spectra of an IR      
    SPICAV observation collected by the two detectors of the infrared channel.
    All other relevant information (parameters of the command, frequency      
    array, system monitor's values) are also included in the file.            
    For more details on that topic  please refeer the                         
    SA_VEX_ARCH_001_05.PDF/.ASC.                                              
                                                                              
******************************************************************************
                                                                              
                                                                              
The GEOMETRY directory will contain geometry files associated to the level 0B 
IR data. The files listed below will be found in this directory.              
                                                                              
                                                                              
                                                                              
      |- [GEOMETRY]   A directory containing the data + associated label files
      |     |                                                                 
      |     |- GEOMINFO.TXT     Description of files in this directory        
      |     |                                                                 
      |     |                                                                 
      |     |-[VENUS]   A directory containing VEX SPICAV level 0B IR geometry
      |     |    |      files associated to data collected during the Venus   
      |     |    |      nominal phase                                         
      |     |    |                                                            
      |     |    |-[VOCP_0001_0022]                                           
      |     |    |    |                                                       
      |     |    |    |- [DOYxxxx]                                            
      |     |    |    |  |                                                    
      |     |    |       |-- {file(s) *TXT, *.LBL}                            
      |     |    |                                                            
      |     |    |-[MTP001_0023_0044]                                         
      |     |    |    |                                                       
      |     |    |    |-[ORBITxxxx]                                           
      |     |    |       |                                                    
      |     |    |       |-- {file(s) *TXT, *.LBL}                            
      |     |    |                                                            
                                                                              
                                                                              
Geometry files provided by the SPICAV team will have the following name:      
                                                                              
SPIV_YYT_nnnnAnn_M_vv_GOXww.DAT                                               
                                                                              
where                                                                         
                                                                              
    YY  2 letters describing the SPICAV data level (eg. 0A, 1A, 0B, ...)      
    T   1 letter describing the type of data collected (U for UV and R for IR)
 nnnn  4 digits for the orbit number or Pmmm (P for VOI PHASE and mmm are the 
          doy number)                                                         
   Ann  sequence number indicating the order that data were collected for the 
        nnnn orbit (A01, A02,...).                                            
    M   1 letter describing the type operation mode (eg.H: EARTH, W: MERCURY, 
         E:STAR,S:SUN,L:LIMB, N:NADIR)                                        
   vv   version number of the file                                            
    X   1 letter describing the content of the file. The value of this letter 
        can be L for a light version of  the geometry file (only some main    
        parameters) and F for a full version.                                 
   ww   version number of the software generating the geometry file