[IGSMAIL-5967]: Continuous L5 Data available at UNAVCO

[Frederick Blume]

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IGS Electronic Mail      09 Jul 10:42:33 PDT 2009      Message Number 5967
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Author: Frederick Blume (UNAVCO)

UNAVCO's Development and Testing Group is pleased to share continuous  
data from a Trimble NetR8 receiver tracking the demonstration L5  
signal from SVN49/PRN01.  Operated as a permanent station "L5DT", the  
receiver was installed on 25-March-2009 using a Trimble GNSS Choke  
Ring (TRM59800.00) mounted on the roof of our headquarters in Boulder,  
CO.  However, L5 was not successfully tracked until 6-May-2009 when L5- 
compatible firmware was received from Trimble.  The receiver is also  
tracking GLONASS and L2C signals where available.

An IGS site log for the station is available at:
ftp://data-out.unavco.org/pub/logs/l5dtlog.txt

Data are available in daily directories (for day-of-year designated as  
DDD) at:
ftp://data-out.unavco.org/private/9aBQ81/2009/DDD

each directory contains a teqc QC file, compressed RINEX 2.11 and  
Hatanaka format observation files and both GPS and GLONASS navigation  
files.  e.g. files for 6-July-2009 are available in the directory:
ftp://data-out.unavco.org/private/9aBQ81/2009/187

which contains files:
l5dt1870.09S
l5dt1870.09d.Z
l5dt1870.09g.Z
l5dt1870.09n.Z
l5dt1870.09o.Z

New data directories are created daily at 1200 UTC for the previous  
day.  Data are also mirrored in the CDDIS L5 test directory:
ftp://cddis.gsfc.nasa.gov/gps/data/l5test/rinex2/daily/2009/


An important detail about the NetR8 receiver and its tracking of L2C  
on SVN49/PRN01:  The receiver is hardware limited to track no more  
than 3 simultaneous pseudoranges from any satellite.  This means that  
then L5 is present it will only track one code from each frequency:   
L1 C/A, L2C, and L5.  For other block IIR-M SV's you'll see that L1 C/ 
A, P2, and L2C are tracked.

I've noticed over time that there have been many instances for SVN49/ 
PRN01 that L2C has been turned off, in some cases for parts of days  
and in some cases for many days.  In this case the NetR8 will track L1  
C/A, P2, and L5.

For example on day 186 (5-July), L2C was disabled on PRN01 after 1200  
UTC:
ftp://data-out.unavco.org/private/9aBQ81/2009/186/l5dt1860.09S

I recommend inspecting QC files when using these data.


Please let me know if you have any questions.  Use of the data should  
be acknowledged according to our policy on the following page:
http://www.unavco.org/community/policies_forms/acknowledgment.html


Thanks,
Freddy Blume


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Dr. Frederick Blume
Sr. Project Manager
UNAVCO
6350 Nautilus Dr.
Boulder, CO  80301-5553
(303)381-7474
http://www.unavco.org
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