[IGSMAIL-2892]: Re: IGS Station specific issues and regional responsiblities

[Ludwig Combrinck]

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IGS Electronic Mail      19 Jun 07:16:58 PDT 2000      Message Number 2892
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Author: Ludwig Combrinck
Subject: IGS stations

Dear IGS Community

In order to prepare our position paper, which will focus on station
specific issues and regional operations we would like to receive some
input from the IGS community at large. Please direct your replies
to me directly (ludwig at hartrao.ac.za) and not to the IGSMAIL exploder.
Please take a couple of minutes to reply, even if you are just a station
host or operator, we need your input ! If you have some serious questions,
concerns, qualms or ideas, take as long as you need...

(1) How are you validating or monitoring:
    (a)  station data integrity ? 
    (b)  data latency ?
    (c)  receiver system integrity such as functioning UPS, lightning
         protection devices, cable and rf connector condition.  
    (d)  What sort of problems are you experiencing with data and
         equipment monitoring ?  Do you have a wish list ? Questions you
         think should be addressed ?

(2) Footprints are used to monitor station site integrity and to tie
    geodetic techniques and reference points. This gives a site the
    capability to determine and quantify sudden anomalies, evaluate site
    stability and monitor baselines between say VLBI, SLR and GPS
    reference points.
    (a) Do you or your institute have the necessary expertise and
        equipment to perform and maintain footprints ?   
    (b) If not, would you be interested in having a footprint done for you
        by someone else, and are you willing to contribute towards the
        costs ?
    (c) What are your opinions regarding footprints ? Please feel free to
        speak your mind.....

(3) GPS geodetic monuments have many variables which influence their
    durability, suitability and stability. Different types, design,
    location, construction material etc. are used. Some are more suitable
    for certain types of location, some are elaborate and expensive, some
    are made to be as durable and stable as possible, others are cheap and 
    nasty from a stability perspective. 
    (a) What is your opinion of your monument ? Tell us what you can
        about it.
    (b) Before installing a monument, you should (preferably) conduct 
        a local geophysical survey, try to optimize the interface between
        the monument and solid clean bedrock, select a location with
        minimum multipathing and other (security, access etc.) problems.
        Not everyone is equipped or willing to go the long way.
        Do you think it would be worthwhile to have a 'Guide to Geodetic
        Monumentation and Installation", which would make things easier ?
        Are you willing to contribute to such a guide ? 

(4) Some regions (globally speaking) are sparsely populated with IGS
    stations. This creates several problems as far as a 'global' IGS
    network is concerned.         
    (a) Do you have some 'older but still good' equipment which could be
        utilised somewhere ? Would you like to make some contribution to
        in another form to densify the IGS network ? How would you like to
        contribute ?
    (b) Do you see this as a regional responsibility and not a global
        responsibility ? Why ?  


(5) What other concerns/questions/suggestions do you have as far as
    station equipment, station and regional responsibilities as well 
    as station specific issues are concerned ?



Thanks in advance for all the replies, we are looking forward
to reading them,

Ludwig Combrinck and Marinda Chin



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Ludwig Combrinck
Programme Leader
HartRAO Space Geodesy Programme
PO BOX 443
Krugersdorp 1740
South Africa
e-mail: ludwig at ludwig.hartrao.ac.za
      : ludwig at bootes.hartrao.ac.za
Tel: +27 12 326-0742
Fax: +27 12 326-0756
IGS Regional Data Center for Africa
URL: http:\\www.hartrao.ac.za\geodesy\geodesy_index.html
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