Subject: [IGSMAIL-4279]: updated <P1-C1> biases and cc2noncc
From: Jim Ray "(NGS" 301-713-2850 "x112)" <[email-masked]>
To: [email-masked]
Date: Wed, 26 Feb 2003 08:14:50 -0500 (EST)

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IGS Electronic Mail      26 Feb 05:15:26 PST 2003      Message Number 4279
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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 with data collected starting 02 Mar 2003 (GPS week
1208):

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

      data bias / -0.067d0, -0.944d0,  0.106d0,  1.508d0, -0.802d0,
     +             0.645d0, -0.916d0, -0.514d0,  0.380d0, -1.480d0,
     +             0.692d0, -9.999d9,  1.503d0,  0.289d0, -0.830d0,
     +            -0.561d0, -0.595d0,  0.084d0, -9.999d9, -1.084d0,
     +            -9.999d9, -1.609d0, -0.740d0,  0.347d0,  0.720d0,
     +             1.223d0, -0.023d0, -0.113d0,  0.867d0,  2.211d0,
     +            -0.296d0, -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 #3674, 08 Jan 2002), these
are based on the 30-day averages (period ending 21 Feb 2003) for the bias
parameters estimated by the CODE Analysis Center (see IGS Mails #2827,
9 May 2000, and #3212, 23 Feb 2001, by Stefan Schaer).

Users will note that significant changes for most PRNs have occurred since
the previous set of <P1-C1> biases.  In addition, the constellation has
changed with the addition of PRN16 and the decommissioning of PRN21.

A new version of the RINEX converter utility, cc2noncc, will be posted at
the IGS Central Bureau later today.  This utility can be used to transform
RINEX data from cross-correlating style receivers (e.g., AOA TurboRogue,
AOA ICS-4000Z, Trimble 4000) or from non-cross-correlator receivers
reporting C1 instead of P1 (e.g., Trimble 4700, Trimble 5700, LEICA RS500,
LEICA CRS1000, LEICA SR9600) to be compatible with modern receiver types.
New runstring options are being implemented to allow an external file of
historic bias corrections to be applied (useful for processing data from
various epochs in the past, not just the most recent epochs) or to force
corrections despite mismatches in receiver types read from the RINEX
headers.  The official file of historic bias values is <p1c1bias.hist>.
Users are free to edit this file for use with cc2noncc using other sets of
bias values, provided that the same format for correction values is used.

The new version of the program (cc2noncc Vers 4.0, 26 Feb 2003) and the
file of historic bias values (p1c1bias.hist) should be available later
today at the IGS Central Bureau at
<ftp://igscb.jpl.nasa.gov/igscb/software/cc2noncc/>

My thanks to Gerd Gendt for his suggested changes and assistance.

--Jim Ray