[IGSMAIL-4987]: updated P1-C1 bias values

[Jim Ray]

******************************************************************************
IGS Electronic Mail      04 Aug 04:29:09 PDT 2004      Message Number 4987
******************************************************************************

Author: Jim Ray

Updated values for the <P1-C1> satellite biases are now available and
recommended for use by all IGS Analysis Centers and users of IGS clock
products beginning at the start of GPS week 1284 (15 Aug 2004):

      average <P1-C1> biases (ns) in PRN order (from PRN01 thru PNR40):

 h 2004 08 15
      data bias / -0.053d0, -9.999d9, -0.011d0,  1.450d0, -0.944d0,
     +             0.538d0, -1.228d0, -0.243d0,  0.401d0, -1.582d0,
     +             0.553d0, -9.999d9,  1.621d0,  0.441d0, -0.948d0,
     +            -0.410d0, -0.835d0,  0.063d0, -2.323d0, -1.074d0,
     +            -0.345d0,  0.605d0, -0.225d0,  0.289d0,  0.570d0,
     +             1.277d0,  0.001d0, -0.204d0,  0.969d0,  2.095d0,
     +            -0.449d0, -9.999d9, -9.999d9, -9.999d9, -9.999d9,
     +            -9.999d9, -9.999d9, -9.999d9, -9.999d9, -9.999d9  /


As with the previous set of biases (IGS Mail #4937, 10 May 2004), these
are based on the monthly average estimates by the CODE Analysis Center
for July 2004 (for background see IGS Mails #2827, 9 May 2000, and
#3212, 23 Feb 2001, by Stefan Schaer).

Please note that since the last update the constellation has changed
with the launch of a new IIR-12 satellite (SVN60/PRN23) on 23 Jun 2004.
Besides the bias change for PRN23, the only others changing by more
than 0.2 ns were PRN07 (-0.42 ns) and PRN08 (+0.32 ns).

The launch of IIR-13 (probably SVN61/PRN02) is currently set for
22 September.

A new version of the program (cc2noncc Vers 4.7, 04 Aug 2004) and the
file of historic bias values (p1c1bias.hist) will be sent to the IGS
Central Bureau where they will be posted at
<ftp://igscb.jpl.nasa.gov/igscb/software/cc2noncc/>.

--Jim Ray