tcsfix: Time Correlation Spacecraft file FIXing task

• SYNOPSIS
  
      tcsfix [clonetcs=yes|no] [rerun=yes|no]
  
• DESCRIPTION
  This task fixes a number of distinct problems in ODF time correlation data:
  1. Due to wrong ground station and spacecraft time propagation delays hardcoded in XSCSv71 all time correlation files produced with these XSCS versions contains too small UTC values. The absolute error is - depending slightly on the GS ID - of the order of 60ms. In addition some of the early TCS files do not contain the ERTIMRAW column that hold the non-propagation delay corrected earth reception times. Also, some early TCS have bogus entries with UTCDAY=0 - those rows are removed from the table.
  2. During revolutions 384 - 394 (both inclusive) the Santiago ground station clock was running exactly one second ahead of UTC. Consequently, the time correlation data show a corresponding discontinuity at the time of a station handover to Santiago (GSID==41).
  3. During several periods in 2002 timing data from the Kourou ground station showed various anomalies which manifests themselves as discontinuities at the time of a handover to/from this station.
  tcsfix does:

   ${}$

  remove rows where UTCDAY=0

   ${}$

  add the ERTTIMRAW column to the TCS unless it exists already

  C1

  if (rev < 207)

  • undo the wrong propagation delays to all UTC fields and applies the correct delays

  C2

  if (rev 384 && rev 394)

  • subtract 1s to UTC data from Santiago station

  C3

  if (observation start/end time lies in a Kourou bad-time window)

  • correct anomalies

   ${}$

  adds attribues
  TCSFIXED = T // this TCS has been fixed
  TCSFIXV = M.m.p // tcsfix version number
  TCSFIXC = id // numerical code of applied corrections
  

  C1 is only done if the revolution number is less than 207 (XSCS-v72 was put online at the beginning of rev 207); C2 is only done for ODFs from revolutions ; C3 is only done if observation start/end time lies within affected time windows. C1/C2/C3 are not performed if the attribute TCSFIXC indicates that these corrections have been applied already in a previous run (to avoid double-correction through repeated invocations of tcsfix. Each set bit in TCSFIXC stands for one distinct applied correction, i.e. TCSFIXC=0 indicates that the data has not been modified.