[IGSMAIL-4318]: New version of ClockPrep program

[Jeff Freymueller]

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IGS Electronic Mail      20 Mar 15:22:44 PST 2003      Message Number 4318
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Author: Jeff Freymueller

Users of the ClockPrep program,

I have just released a new version of my program ClockPrep (version
1.90, 3/10/2003). The previous version was dated exactly one year ago.
Some of you may have a much older version on your systems.

Some of you are aware that ClockPrep had problems with Trimble (and some
Ashtech) RINEX files that were created as hourly files, and then merged.
In the case of Trimble files, this resulted in jumps in the phase at
every hour, which result in cycle slips when processed. The exact reason
for this takes some explaining, so I'll skip it (email me if you really
want to know), but the bottom line is that a file made from merging
several rinex files is not the same as a file in which the raw files are
merged before rinexing.

Last month, Kristine Larson figured out a solution to this problem. It
is necessary to keep track of the number of millisecond offsets
separately for the code and phase observables. I have implemented
Kristine's fix, generalized it a bit, and it passes all of my test case
files so I believe it is reliable. For files that were not constucted by
merging hourly rinex files, this version should give the same result as
the previous version.


The source code, sun and Linux executables are located at:
ftp://giseis.alaska.edu/pub/USERS/jeff/software/clockprep.tar.Z

Please let me know if you have any problems with this version.

Jeff


Dr. Jeffrey T. Freymueller         Office: 907-474-7286
Geophysical Institute              Fax:    907-474-7290
University of Alaska, Fairbanks    Home:   907-479-3550
PO Box 757320                      Cell:   907-322-7632
Fairbanks, AK 99775-7320           email: jeff at giseis.alaska.edu or 
jeff.freymueller at gi.alaska.edu
URL: http://www.aeic.alaska.edu/Input/jeff/jeff.html

Download Alaska GPS data: http://www.aeic.alaska.edu/Input/akda/