Stability and accuracy of GPS P3 TAI time links

In April 2002, a pilot experiment was initiated by the BIPM in order to study the use of GPS P3 code measurements obtained with geodetic type dual frequency receivers to compute time links. For several time links, independent computations using two or three different techniques may be carried out and compared to assess the stability of each technique. This paper presents several such comparisons that show that the stability of GPS P3 is below 1 ns (one standard deviation) for averaging times between a few hours and several months. After more than one year of operation, such time links were introduced into TAI computation starting June 2003.