T2L2 Time Transfer by Laser Link

Christian Veillet, Patricia Fridelance

Abstract:	T2L2 (Time Transfer by Laser Link) is a new generation time transfer experiment based on the principles of LASSO (Laser Synchronization from Synchronous Orbit) and used with an operational procedure developed at OCA (Observatoire de la Cote d'Azur) during the active intercontinental phase of LASSO. The hardware improvements could lead to a precision better than 10 ps for time transfer (flying clock monitoring or ground based clock comparison). Such a package could fly on any spacecraft with a stable clock. It is developed in France in the frame of the PHARAO project (cooled atom clock in orbit) involving CNES and different laboratories. But T2L2 could fly on any spacecraft carrying a stable oscillator. A GPS satellite would be a good candidate, as T2L2 could allow to link the flying clock directly to ground clocks using light, aiming to important accuracy checks, both for time and for geodesy. Radioastron (a flying VLBI antenna with a H-maser) is also envisioned, waiting for a PHARAO flight. The ultimate goal of T2L2 is to be part of more ambitious missions, as SORT (Solar Orbit Relativity Test), aiming to examine aspects of the gravitation in the vicinity of the Sun.
Published in:	Proceedings of the 26th Annual Precise Time and Time Interval Systems and Applications Meeting December 6 - 8, 1994 Hyatt Regency Reston Town Center Reston, Virginia
Pages:	443 - 454
Cite this article:	Veillet, Christian, Fridelance, Patricia, "T2L2 Time Transfer by Laser Link," Proceedings of the 26th Annual Precise Time and Time Interval Systems and Applications Meeting, Reston, Virginia, December 1994, pp. 443-454.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In