Azadeh Aghamohammai - National Cartographic Center of Iran Meraj Av. Azadi Sq. Tehran Iran
Hamidreza Nankali
Yahya Djamuor

This document provides a practical solution to the transformation of International Terrestrial Reference Frame (ITRF2000) coordinates of Iranian permanent GPS Network into WGS84 system. WGS84 is geocentric coordinate datum most fit to geoid in Iran (±3cm) and is used as a reference ellipsoid. IPGN coordinates are in ITRF2000. ITRF coordinates will in general differ from WGS84coordinates, for two reasons, tectonic motions and reference frame difference. The convergent rate is approximately 2.2cm/year in NE direction (Jaeksan & Mackenzie 1984) (Vernant 2004). Differences between the ITRF2000 coordinate reference frame and the WGS84 are at the several cm in magnitude. A standard 7-parameter transformation can adequately model these differences at the cm level. Two model have been tested, Bursa-Wolf and Molodensky transformation models. Between these two, Bursa Wolf had the better result and can be used as a better long-term practical solution to these coordinate transformations.

Transformation, ITRF, WGS84, IPGN, coordinates, GPS network