= GNSS Base station repositories =

Here are some sites that you can look at to find GPS (GNSS) base stations for use in differential GPS processing.

 1. [https://www.ordnancesurvey.co.uk/gps/os-net-rinex-data/ OS National GPS Network] - Base station data for the UK. FTP download from ftp://www.ordnancesurvey.co.uk/gps/rinex
 1. [https://www.ordnancesurvey.co.uk/gps/os-net-rinex-data/ OS-Net] - Base station data for the UK. [https://www.ordnancesurvey.co.uk/gps/rinex/ Direct link to data]
 1. [http://smartnet.leica-geosystems.co.uk/SpiderWeb/SmartNet/smartnet.html Leica SmartNet] - Think this data is probably the same as that available direct from OS? [https://rsg.pml.ac.uk/intranet/trac/wiki/Projects/ARSF-DAN/Passwords Login details]
 1. [http://igscb.jpl.nasa.gov/ IGS] - Global station network, but sparse
  * [http://igscb.jpl.nasa.gov/network/list.html Station list]
 1. [http://www.unavco.org/ UNAVCO] - Global, permanent and campaign stations, sparse
  * [http://facility.unavco.org/data/dai2/app/dai2.html# Station search app]
 1. [http://www.eupos.org/ EUPOS] - Central/Eastern European network - regional coverage only but dense.
  * [http://www.eupos.hu/EUPOS-ESDB.php Station database]
  * [http://www.eupos.hu/map_out.php Station map]
 1. [http://www.epncb.oma.be/ EUREF] - European regional coverage, quite dense, requires registration (and possibly using their download client)
  * [http://www.epncb.oma.be/_dataproducts/data_access/real_time/ Real time data access]
 1. [http://www.trimble.com/findtrs.asp Trimble reference station list] - some overlap with IGS, global but sparse again
 1. [http://cddis.nasa.gov/ CDDIS] - Don't think they operate any stations themselves, just store data from IGS stations
  * [http://cddis.nasa.gov/gnss_datasum.html Data access page]