A new approach for steering UTC(KRIS)

This paper describes the development of a steering strategy that is intended to improve the frequency stability of UTC (KRIS). An experimental time scale is supposed to be generated by steering an active H-maser with carrier-phase (CP) GPS time transfer. One of the goals of this paper is to achieve an improved long-term frequency stability and, at the same time, not seriously perturb the short-term stability of the H-maser. Emphasis is placed on the fact that a real-time GPS CP time transfer is utilized to compute the time difference. The Kalman estimator is utilized for the GPS time transfer, and the optimal control technique is employed to steer the H-maser toward the reference clock, which is the GPS system time (GPST) in this case. The expected performance of the strategy is assessed based on the actual six-month data of the UTC (KRIS), and the relative performance assessment is conducted with respect to the frequency instability by comparing it against the currently operational time scale of the UTC(KRIS).

[1]  Per Jarlemark,et al.  Real-Time Time and Frequency Transfer Using GPS Carrier Phase Observations , 2003 .

[2]  Bob E. Schutz,et al.  A study on the Common-View and All-in-View GPS time transfer using carrier-phase measurements , 2008 .

[3]  T.E. Parker,et al.  Assessment of GPS carrier-phase stability for time-transfer applications , 2000, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[4]  D. Matsakis.  Time and frequency activities at the U.S. naval observatory , 2005, Proceedings of the 2005 IEEE International Frequency Control Symposium and Exposition, 2005..

[5]  Gene F. Franklin,et al.  Digital control of dynamic systems , 1980 .

[6]  Demetrios Matsakis,et al.  New Steering Strategies for the USNO Master Clocks , 1999 .

[7]  R. Dach,et al.  Comparison between frequency standards in Europe and the USA at the 10−15 uncertainty level , 2006 .

[8]  Richard A. Brown,et al.  Introduction to random signals and applied kalman filtering (3rd ed , 2012 .

[9]  C. Rieck,et al.  First results of real-time time and frequency transfer using GPS code and carrier phase observations , 2003, IEEE International Frequency Control Symposium and PDA Exhibition Jointly with the 17th European Frequency and Time Forum, 2003. Proceedings of the 2003.

[10]  Pierre Héroux,et al.  Precise Point Positioning Using IGS Orbit and Clock Products , 2001, GPS Solutions.

[11]  A. Bauch,et al.  A new realization strategy for the time scale UTC(PTB) , 2004, Proceedings of the 2004 IEEE International Frequency Control Symposium and Exposition, 2004..

[12]  P. Koppang,et al.  Linear quadratic stochastic control of atomic hydrogen masers , 1999, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.