TWSTFT has been recognized as the most precise and accurate means for remote clock comparisons and is thus widely used in the time and frequency community, including institutions and organizations affiliated with telecommunication administrations. Operational practice of TWSTFT and the equipment involved have changed considerably since the first and second issue of Recommendation ITU-R TF.1153 were released in 1997 and 2003, respectively. The current version takes care of this.
ITU-R TF.1153-3-2010 history
0000 ITU-R TF.1153-2015
2010ITU-R TF.1153-3-2010 The operational use of two-way satellite time and frequency transfer employing pseudorandom noise codes