Advances in Radio Science www.adv-radio-sci.net 1684-9965 1684-9973 2 Kleinheubacher Berichte 2003 2004 10.5194/ars-2-269-2004 http://www.adv-radio-sci.net/2/269/2004/ http://www.adv-radio-sci.net/2/269/2004/ars-2-269-2004.html http://www.adv-radio-sci.net/2/269/2004/ars-2-269-2004.pdf 269 273 2005-05-27 GPS TEC and ITEC from digisonde data compared with NEQUICK model J.-C. Jodogne H. Nebdi R. Warnant Institut Royal Météorologique, 3 Avenue Circulaire, B-1180 Bruxelles, Belgium Royal Observatory of Belgium At the Dourbes station, a digisonde 256 is colocated with a Turbo Rogue GPS receiver. Real time processing of the digisonde data gives the electron density profile and the ITEC value (SAO file) for each sounding. The GPS receiver produces data that are treated at the Royal Observatory in order to extract a vertical TEC. Running the wellknown NeQuick ionospheric model allows to compute vertical TEC values. Comparisons of the results obtained in 1996 and 2001 by these different approaches are shown.