[IGSMAIL-5771]: Model changes made at CODE

[Stefan Schaer]

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IGS Electronic Mail      14 May 07:09:48 PDT 2008      Message Number 5771
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Author: Stefan Schaer, Rolf Dach


Dear IGS colleagues,

A number of model changes/improvements was activated in CODE's IGS
analysis starting with GPS week 1477:

- Computer platform change from SunOS 5.9 to Linux, x86_64:

  This change affects all of our IGS analysis processes, with the
  exception of the ionosphere prediction and DCB combination procedures
  (which are still running on the old platform and therefore caused
  that corresponding product files were temporarily unavailable, but
  are generated again in a nominal schedule).

The new computer system is more powerful and allowed us to implement
the following model refinements:

- Inclusion of all available NGA stations in our GNSS orbit and
  ionosphere analysis:
 
  This includes the following 12 stations:

    S011/U012             St. Louis, US        
    S021/U022 50109S001   Salisbury, AU        
    S031/U032 41505S007   Buenos Aires, AR     
    S041/U042 13235S001   Hermitage, UK        
    S051/U052 24901M002   Manama, BH           
    S061/U062 42003S003   Quito, EC            
    S071/U072 40451S005   Washington, US       
    S101/U102 49805S001   Eielson AFB, US      
    S111/U112 50208S003   Wellington, NZ       
    S121/U122 30310S001   Pretoria, ZA         
    S131/U132 23904S001   Osan AB, KP          
    S141/U142             Tahiti, PF

  Main stations are indicated with a leading S, backup stations with U.
  Currently unavailable seem to be:

    S021/U022
    S041/U042
    S051/U052

  It is worth mentioning that BAHR is sharing its antenna with S051 and
  U052 (indicated with identical M-type DOMES number):

    BAHR      24901M002   Manama, BH

  BAHR's antenna height of 3.1220 m is therefore adopted to S051 and
  U052. All other height values are kept to 0.0000 m. Until a
  definitive IGS naming convention (rcvr_ant.tab) is available, we use:
    ASHTECH Z-XII3 / ASH700936B_M SNOW.

  NGA stations start to appear in all our analysis products:
    weekly SINEX (and analysis summary),
    daily IONEX (P1-P2 DCB) results, and
    daily clock RINEX files (starting with GPS week 1478).

- Setup of GNSS satellite antenna PCV parameters specific to each
  individual satellite commenced (for later retrieval).

- Time resolution for EOP estimation increased internally (from 2 to
  1 hr).
  Note: The ERP results submitted to the IGS continue to be conform
  with a time resolution of 1 day (24 hours).

Two new products are considered at CODE:

- Provision of phase-consistent high-rate (5-sec) GPS satellite clock
  values.
  Note: Submission of corresponding files (named CODwwwwd.CLK_05S.Z)
  to the IGS data centers will start with GPS week 1478. 

- Generation of GNSS rapid SINEX files containing station coordinates and
  ERPs with a time resolution of 6 hours is foreseen as a contribution for
  the IERS inter-technique combination.

The two mentioned new products are accessible at the common location of all
other CODE GNSS analysis products :

  http://www.aiub.unibe.ch/download/CODE/
  ftp://ftp.unibe.ch/aiub/CODE/

Best regards,

The CODE AC Team