COMPARISONS OF CLOCKS BY GPS AND TWSTFT

The GPS has served the principal needs of national timing laboratories for regular comparisons of remote atomic clocks for the last two decades. GPS common-view time transfer is, however, barely sufficient for comparison of today’s atomic clocks within a few days. For this reason the timing community is engaged in the development of new approaches to time and frequency comparisons, among them is the two-way satellite time and frequency transfer (TWSTFT). This paper describes impact of time transfer on the computation of International Atomic Time and a comparison of single-channel GPS C/A-code common-view time transfer and TWSTFT